RU2778704C2 - Immunogenic compositions containing conjugated capsular saccharide antigens and use thereof - Google Patents

Abstract

FIELD: biochemistry; immunology.

SUBSTANCE: invention refers to biochemistry and immunology. Disclosed is an immunogenic composition for use as a vaccine for preventing a condition associated with S. pneumoniae, containing a glycoconjugate of isolated capsular polysaccharide S. pneumoniae serotype 22F with protein-carrier CRM197, and excipient.

EFFECT: invention can be used for vaccination of subjects against pneumococcal infections.

19 cl, 16 dwg, 20 ex, 25 tbl

Description

Field of invention

The present invention relates to novel immunogenic compositions containing conjugated capsular saccharide antigens (glycoconjugates) and their uses. The immunogenic composition of the present invention will typically contain glycoconjugates wherein the saccharides are derived from Streptococcus pneumoniae serotypes. The invention also relates to the vaccination of human subjects, in particular infants and the elderly, against pneumococcal infections using said new immunogenic compositions.

Prerequisites for the creation of the invention

Infectious diseases caused by pneumococci are the leading cause of morbidity and mortality worldwide. Pneumonia, febrile bacteremia, and meningitis are the most common manifestations of invasive pneumococcal infections, while bacterial spread in the respiratory tract can result in middle ear infection, sinusitis, or recurrent bronchitis. Compared with invasive disease, non-invasive manifestations tend to be less severe but significantly more widespread. In Europe and the United States, pneumococcal pneumonia is the most common community-acquired bacterial pneumonia, estimated to affect approximately 100 per 100,000 adults each year. The corresponding figures for febrile bacteremia and meningitis are 15-19 per 100,000 and 1-2 per 100,000, respectively. The risk of one or more of these manifestations is significantly higher in children and the elderly, as well as immunocompromised individuals of any age. Even in economically developed regions, invasive pneumococcal disease carries a high mortality rate; for adults with pneumococcal pneumonia, the mortality rate averages 10%-20%, while it can exceed 50% in high-risk groups. Pneumonia is by far the most common cause of pneumococcal death worldwide.

The etiological agent of pneumococcal disease, Streptococcus pneumoniae (pneumococcus), is a gram-positive encapsulated cocci surrounded by a polysaccharide capsule. Differences in the composition of this capsule provide serological differentiation between approximately 91 capsule types, some of which are often associated with pneumococcal disease, others less frequently. Invasive pneumococcal infections include pneumonia, meningitis, and febrile bacteremia; common non-invasive manifestations are otitis media, sinusitis and bronchitis.

Pneumococcal conjugate vaccines (PCV) are pneumococcal vaccines used to protect against diseases caused by S. pneumoniae (pneumococci). There are currently three PCV vaccines available on the world market: PREVNAR ^® (called prevenar in some countries) (a heptavalent vaccine), SYNFLORIX ^® (a decavalent vaccine) and PREVNAR 13 ^® (a tridecavalent vaccine).

The recent development of widespread microbial resistance to major antibiotics and the increasing number of people with impaired immunological reactivity highlights the need for pneumococcal vaccines with even broader protection.

In particular, there is a need to address the continuing unmet medical need to cover pneumococcal diseases caused by serotypes not found in PREVNAR 13 ^® and the potential for serotype substitution over time. The specific serotypes that cause diseases other than 13 in PREVNAR 13 ^® vary by region, population, and may change over time due to the acquisition of antibiotic resistance, the introduction of pneumococcal vaccine, and a long-term trend of unknown origin. There is a need for an immunogenic composition that can be used to induce an immune response against additional serotypes of Streptococcus pneumoniae in humans and in particular in children less than 2 years of age.

The objective of the new immunogenic compositions according to the present invention is to provide adequate protection against S. Pneumoniae serotypes not found in PREVNAR 13 ^® . In one aspect, the objective of the immunogenic composition according to the present invention is to provide adequate protection against S. pneumoniae serotypes not found in PREVNAR ^® (heptavalent vaccine), SYNFLORIX ^® and/or PREVNAR 13 ^® , while maintaining an immune response against serotypes currently covered by the indicated vaccines.

Brief summary of the invention

The present invention relates to an immunogenic composition comprising at least one glycoconjugate selected from the group consisting of a glycoconjugate from S. pneumoniae serotype 15B, a glycoconjugate from S. pneumoniae serotype 22F, a glycoconjugate from S. pneumoniae serotype 33F, a glycoconjugate from S. pneumoniae serotype 12F, glycoconjugate from S. pneumoniae serotype 10A, glycoconjugate from S. pneumoniae serotype 11A, and glycoconjugate from S. pneumoniae serotype 8.

In one aspect, the invention provides an immunogenic composition comprising at least one glycoconjugate from S. pneumoniae serotype 15B, at least one glycoconjugate from S. pneumoniae serotype 22F, and at least one glycoconjugate from S. pneumoniae serotype 33F.

In another aspect, the invention provides an immunogenic composition comprising at least one glycoconjugate from S. pneumoniae serotype 15B, at least one glycoconjugate from S. pneumoniae serotype 22F, at least one glycoconjugate from S. pneumoniae serotype 33F, at least one glycoconjugate from S. pneumoniae serotype 12F, at least one glycoconjugate from S. pneumoniae serotype 10A, at least one glycoconjugate from S. pneumoniae serotype 11A, and at least one glycoconjugate from S. pneumoniae serotype 8.

In one aspect, the above immunogenic composition further comprises glycoconjugates from S. pneumoniae serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F.

In another aspect, the above immunogenic composition further comprises glycoconjugates from S. pneumoniae serotypes 1, 5 and 7F.

In another aspect, the above immunogenic composition further comprises glycoconjugates from S. pneumoniae serotypes 6A and 19A.

In another aspect, the above immunogenic composition further comprises glycoconjugates from S. pneumoniae serotype 3.

In another aspect, the above immunogenic composition further comprises glycoconjugates from S. pneumoniae serotype 2, 9N, 17F, 20 and/or 15C.

In one aspect, the above immunogenic composition does not contain a capsular saccharide from S. pneumoniae serotype 9N, 9A and/or 9L.

In one aspect, the above immunogenic composition is a 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20-valent pneumococcal conjugate composition. In one aspect, the above immunogenic composition is 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25-valent pneumococcal conjugate composition.

In one aspect, the glycoconjugates are individually conjugated to a carrier protein selected from the group consisting of DT (diphtheria toxin), TT (tetanus toxin), CRM ₁₉₇ , other DT mutants, PD (hemophilic influenza type D), or their immunologically functional equivalents.

In one aspect, the invention provides a container filled with any immunogenic composition defined in the present document.

In one aspect, the invention provides any immunogenic composition defined in the present document for use as a drug, in particular for use as a vaccine.

In one aspect, the invention provides a method of preventing, treating, or ameliorating an infection, disease, or condition associated with S. pneumoniae in a subject, comprising administering to the subject an immunologically effective amount of any immunogenic composition as defined herein.

figures

Figure 1 shows the repeating polysaccharide structure of the capsular polysaccharide of S. pneumoniae serotype 8 (Pn-8).

Figure 2 shows the repeating polysaccharide structure of the capsular polysaccharide of S. pneumoniae serotype 10A (Pn-10A).

Figure 3 shows the repeating polysaccharide structure of the S. pneumoniae serotype 11A (Pn-11A) capsular polysaccharide.

Figure 4 shows the repeating polysaccharide structure of the S. pneumoniae serotype 12F (Pn-12F) capsular polysaccharide.

Figure 5 shows the repeating polysaccharide structure of the capsular polysaccharide of S. pneumoniae serotype 15B (Pn-15B).

Figure 6 shows the repeating polysaccharide structure of the S. pneumoniae serotype 22F (Pn-22F) capsular polysaccharide.

Figure 7 shows the repeating polysaccharide structure of the capsular polysaccharide of S. pneumoniae serotype 33F (Pn-33F).

Figure 8 shows a flowchart of a typical activation process (A) and conjugation processes (B) that can be used in the preparation of a Pn-33F glycoconjugate.

Figure 9 shows the effect on DO by changing the amount of NCS in the TEMPO/NCS oxidation reaction.

Figure 10 shows the evaluation of the stability of Pn-12F glycoconjugates. Figure 11 Cross-functional OPA responses. A subset of 59 sera from adults vaccinated with the 13 valent pneumococcal conjugate vaccine (Study US 6115A1-004; Clinical Studies - edited, identifier: NCT00427895) was evaluated in the OPA for the presence of functional antibodies against serotypes 9V, 9A, 9L and 9N. The percentage of samples with an OPA positive titer (ie, ≥1:8) is presented for each group above. Geometric mean titers (GMT) are listed on the x-axis below each group.

Figure 12 Cross-functional OPA responses of sixty-six corresponding pre/post sera. A subset of 66 matching panels of pre- and post-vaccination sera from adults vaccinated with 13-valent pneumococcal conjugate vaccine (Study 6115A1-3005; Clinical Trials - Edit, Identifier: NCT00546572) were evaluated in the OPA for the presence of functional antibodies against serotypes 9V, 9A, 9L and 9N. The percentage of samples with an OPA positive titer (ie, ≥1:8) is presented for each group above. Geometric mean titers (GMT) are listed on the x-axis below each group.

Figure 13 Inverse cumulative distribution curves (RCDC) before and after immunization - pneumococcal serotype 9V (Pn9V).

Inverse cumulative distribution curves of OPA titers to serotype 9V from the corresponding panel of pre- and post-vaccination sera (N=66) vaccinated with 13-valent pneumococcal conjugate vaccine (Study 6115A1-3005; Clinical Studies - Government Identifier: NCT00546572). Graphs represent the percentage of sera with an OPA positive titer (ie, ≥1:8).

Figure 14 Inverse cumulative distribution curves (RCDC) before and after immunization - pneumococcal serotype 9A (Pn9A).

Inverse cumulative distribution curves of OPA titers to serotype 9A from the respective panel of pre- and post-vaccination sera (N=66) vaccinated with 13-valent pneumococcal conjugate vaccine (Study 6115A1-3005; Clinical Studies - edited, identifier: NCT00546572). Graphs represent the percentage of sera with an OPA positive titer (ie, ≥1:8).

Figure 15 Inverse cumulative distribution curves (RCDC) before and after immunization - pneumococcal serotype 9L (Pn9L).

Inverse cumulative distribution curves of OPA titers to serotype 9L from a respective panel of pre- and post-vaccination sera (N=66) vaccinated with 13-valent pneumococcal conjugate vaccine (Study 6115A1-3005; Clinical Studies - edited, ID: NCT00546572). Graphs represent the percentage of sera with an OPA positive titer (ie, ≥1:8).

Figure 16 Inverse cumulative distribution curves (RCDC) before and after immunization - pneumococcal serotype 9N (Pn9N).

Inverse cumulative distribution curves of OPA titers to serotype 9N from the corresponding panel of pre- and post-vaccination sera (N=66) vaccinated with 13-valent pneumococcal conjugate vaccine (study 6115A1-3005; Clinical studies - edited, identifier: NCT00546572). Graphs represent the percentage of sera with an OPA positive titer (ie, ≥1:8).

1 Immunogenic composition according to the invention

The immunogenic composition according to the present invention will typically contain conjugated capsular saccharide antigens (also referred to as glycoconjugates) in which the saccharides are derived from S. pneumoniae serotypes.

Preferably, the number of S. pneumoniae capsular saccharides can range from 8 different serotypes (or "v", valency) to 20 different serotypes (20v). In one embodiment, there are 8 different serotypes. In one embodiment, there are 9 different serotypes. In one embodiment, there are 10 different serotypes. In one embodiment, there are 11 different serotypes. In one embodiment, there are 12 different serotypes. In one embodiment, there are 13 different serotypes. In one embodiment, there are 14 different serotypes. In one embodiment, there are 15 different serotypes. In one embodiment, there are 16 different serotypes. In one embodiment, there are 17 different serotypes. In one embodiment, there are 18 different serotypes. In one embodiment, there are 19 different serotypes. In one embodiment, there are 20 different serotypes. The capsular saccharides are conjugated to a carrier protein to form glycoconjugates as described herein below.

If the carrier protein is the same for 2 or more saccharides in the composition, the saccharides can be conjugated to the same carrier protein molecule (carrier molecules that have 2 or more different saccharides conjugated to them) [see e.g. WO 2004 /083251].

In a preferred embodiment, although the saccharides are each individually conjugated to different carrier protein molecules (wherein each carrier protein molecule has only one type of saccharide conjugated to it). In this embodiment, the capsular saccharides are said to be individually conjugated to a carrier protein.

For the purposes of the invention, the term 'glycoconjugate' indicates a capsular saccharide covalently linked to a carrier protein. In one embodiment, the capsular saccharide is linked directly to the carrier protein. In a second embodiment, the bacterial saccharide is linked to the protein via a spacer/linker.

1.1 Carrier protein of the invention

The glycoconjugate component of the invention is the carrier protein to which the saccharide is conjugated. The terms "carrier protein" or "carrier protein" or "carrier" may be used interchangeably herein. Carrier proteins must be suitable for standard conjugation procedures.

In a preferred embodiment, the glycoconjugate carrier protein is selected from the group consisting of: DT (diphtheria toxin), TT (tetanus toxin) or fragment C of TT, CRM ₁₉₇ (a non-toxic but antigenically identical variant of diphtheria toxin), other DT mutants ( such as CRM176, CRM228, CRM45 (Uchida et al. (1973) J. Biol. Chem. 218: 3838-3844), CRM9, CRM102, CRM103 or CRM107; and other mutations described by Nicholls and Youle in Genetically Engineered Toxins, Ed : Frankel, Maecel Dekker lnc.(1992) deletions or mutations of Glu-148 to Asp, Gin or Ser and/or Ala 158 to Gly and other mutations disclosed in US Pat. one or more Lys 516, Lys 526, Phe 530 and/or Lys 534 residues and other mutations disclosed in US Patent Nos. 5,917,017 and 6,455,673 or a fragment disclosed in US Patent No. 5,843,711 pneumococcal pneumolysin (ply) (Kuo et al (1995) Infect Immun 63: 2706-2713), including ply detoxified with any way, for example, dPLY-GMBS (WO 2004/081515, WO 2006/032499) or dPLY-formalin, PhtX, including PhtA, PhtB, PhtD, PhtE (PhtA, PhtB, PhtD or PhtE sequences are disclosed in WO 00/37105 and WO 00/39299) and fusion products of Pht proteins, e.g. PhtDE fusion products, PhtBE fusion products, Pht A-E (WO 01/98334, WO 03/054007, WO 2009/000826), OMPC (meningococcal outer membrane protein), which is usually extracted from Neisseria meningitidis serogroup B (EP0372501), PorB (from N. meningitidis), PD (Haemophilus influenzae protein D); see for example EP0594610 B), or their immunologically functional equivalents, synthetic peptides (EP0378881, EP0427347), heat shock proteins (WO 93/17712, WO 94/03208), pertussis proteins (WO 98/58668, EP0471177), cytokines, lymphokines, growth factors or hormones (WO 91/01146), artificial proteins containing multiple epitopes of human CD4+ T cells from various pathogenic derived antigens (Falugi et al. (2001) Eur J Immunol 31: 3816-3824), such as N19 protein (Baraldoi et al. (2004) Infect Immun 72: 4884-4887) pneumococcal surface protein PspA (WO 02/091998), iron uptake proteins (WO 01/72337), Clostridium difficile toxin A or B (WO 00/61761) , transferrin-binding proteins, pneumococcal adhesion proteins (PsaA), recombinant Pseudomonas aeruginosa exotoxin A (in particular, their non-toxic mutants (such as exotoxin A carrying substitution in glutamic acid 553 (Douglas et al. (1987) J. Bacteriol. 169 ( 11): 4967-4971)).Other proteins such as ova albumin, keyhole limpet limpet hemocyanin (KLH), bovine serum albumin (BSA) or purified protein, tuberculin derivative (PPD) can also be used as carrier proteins. Other suitable carrier proteins include inactivated bacterial toxins such as cholera toxoid (eg as described in WO 2004/083251), Escherichia coli LT, E. coli ST, and exotoxin A from P. aeruginosa.

In a preferred embodiment, the glycoconjugate carrier protein is independently selected from the group consisting of TT, DT, DT mutants (such as CRM ₁₉₇ ), H. influenzae protein D, PhtX, PhtD, PhtDE fusion products (particularly those described in WO 01/98334 and WO 03/054007), detoxified pneumolysin, PorB, N19 protein, PspA, OMPC, C. difficile toxin A or B, and PsaA.

In one embodiment, the glycoconjugate carrier protein of the invention is DT (diphtheria toxoid). In another embodiment, the glycoconjugate carrier protein of the invention is TT (tetanus toxin).

In another embodiment, the glycoconjugate carrier protein of the invention is PD (H. influenzae protein D; see eg EP 0594610 B).

In a preferred embodiment, the capsular saccharides of the invention are a CRM ₁₉₇ conjugated protein. The CRM ₁₉₇ protein is a non-toxic form of diphtheria toxin, but is immunologically distinct from diphtheria toxin. CRM ₁₉₇ is produced by Corynebacterium diphtheriae infected with the non-toxigenic phage β197 ^tox- created by nitrosoguanidine mutagenesis of the toxigenic Corynebacterium beta (Uchida et al. (1971) Nature New Biology 233: 8-11). The CRM ₁₉₇ protein has the same molecular weight as diphtheria toxin, but differs from it by a single base change (guanine to adenine) in the structural gene. This single base change causes an amino acid substitution (glutamic acid to glycine) in the mature protein and eliminates the toxic properties of diphtheria toxin. The CRM ₁₉₇ protein is a safe and effective T cell associated with a saccharide carrier. More information about CRM ₁₉₇ and their preparation can be found, for example, in US patent No. 5,614,382. In one embodiment, the capsular saccharides of the invention are conjugated to the CRM-197 protein or CRM ₁₉₇ A chain (see CN 103495161). In one embodiment, the capsular saccharides of the invention are conjugated to a CRM ₁₉₇ A chain obtained by expression with a genetically recombinant E. coli (see CN 103495161). In one embodiment, all capsular saccharides of the invention are CRM ₁₉₇ conjugated. In one embodiment, all capsular saccharides of the invention are conjugated to the CRM ₁₉₇ A chain.

Accordingly, in numerous embodiments, the glycoconjugates of the invention comprise CRM ₁₉₇ as a carrier protein in which the capsular polysaccharide is covalently linked to CRM ₁₉₇ .

1.2 Capsular saccharide according to the invention

The term "saccharide" throughout this specification may refer to a polysaccharide or an oligosaccharide and includes both. In numerous embodiments, the saccharide is a polysaccharide, in particular the S. pneumoniae capsular polysaccharide.

Capsular polysaccharides are prepared according to standard procedures known to those skilled in the art.

In the present invention, capsular polysaccharides can be obtained, for example, from serotypes 1, 3, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F and 33F S. pneumoniae. Typically, capsular polysaccharides are prepared by growing each S. pneumoniae serotype in a medium (e.g., soy-based media), the polysaccharides are then obtained from a bacterial culture, the S. pneumoniae bacterial strains used to obtain the corresponding polysaccharides, which are used in glycoconjugates according to the invention can be obtained from adapted collections of cultures or clinical samples.

The population of the organism (each serotype of S. pneumoniae) is often expanded from inoculum growth vials to inoculum growth flasks and passaged through one or more seed fermenters, increasing volume until increased fermentation volumes are obtained. At the end of the growth cycle, the cells are lysed and the lysate broth is then collected for a downstream processing (purification) process (see, for example, WO 2006/110381, WO 2008/118752, and U.S. Patent Application Publication Nos. 2006/0228380, 2006/0228381, 2008/0102498 and 2008/0286838).

Individual polysaccharides are typically purified using centrifugation, precipitation, ultrafiltration and/or column chromatography (see, for example, WO 2006/110352 and WO 2008/118752).

Purified polysaccharides can be activated (eg, chemically activated) to make them reactive (eg, with the eTEC spacer) and then incorporated into the glycoconjugates of the invention, as further described herein.

S. pneumoniae capsular polysaccharides contain repeating oligosaccharide units that can contain up to 8 sugar residues.

In one embodiment, the capsular saccharide of the invention may be one oligosaccharide unit or shorter than the length of the native saccharide chain of the repeating oligosaccharide units. In one embodiment, the capsular saccharide of the invention is a single repeating oligosaccharide unit of the appropriate serotype.

In one embodiment, the capsular saccharide of the invention may be oligosaccharides. Oligosaccharides have a low number of repeat units (typically 5-15 repeat units) and are generally obtained synthetically or by hydrolysis of polysaccharides.

Preferably, all of the capsular saccharides according to the present invention and in the immunogenic composition according to the present invention are polysaccharides. High molecular weight capsular polysaccharides are able to induce certain immune responses to antibodies due to the epitopes present on the antigenic surface. The isolation and purification of high molecular weight capsular polysaccharides is preferably contemplated for use in the conjugates, compositions and methods of the present invention.

In some embodiments, the purified polysaccharides have a molecular weight of 10 kDa to 4000 kDa prior to conjugation. In other such embodiments, the polysaccharide has a molecular weight of 50 kDa to 4000 kDa. In further such embodiments, the polysaccharide has a molecular weight of 50 kDa to 3500 kDa; from 50 kDa to 3000 kDa; from 50 kDa to 2500 kDa; from 50 kDa to 2000 kDa; from 50 kDa to 1750 kDa; from 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 100 kDa to 4000 kDa; from 100 kDa to 3500 kDa; from 100 kDa to 3000 kDa; from 100 kDa to 2500 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 1750 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 200 kDa to 4000 kDa; from 200 kDa to 3500 kDa; from 200 kDa to 3000 kDa; from 200 kDa to 2500 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1750 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The polysaccharide may become slightly smaller in size during conventional purification procedures. In addition, as described herein, the polysaccharide may be subjected to sizing procedures prior to conjugation. Mechanical or chemical sizing can be used. Chemical hydrolysis can be carried out using acetic acid. Mechanical sizing can be carried out using fragmentation by high pressure homogenization. The molecular weight ranges indicated above refer to purified polysaccharides before conjugation (eg, before activation).

In a preferred embodiment, the purified polysaccharides are capsular polysaccharides from serotypes 1, 3, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F, or 33F S. pneumoniae, where the capsular polysaccharide has a molecular weight that falls within one of the molecular weight ranges as described herein above.

As used herein, the term "molecular weight" of a polysaccharide or carrier protein-polysaccharide conjugate refers to the molecular weight calculated using gel permeation chromatography (SEC) in combination with a multi-angle laser scatter detector (MALLS).

In some embodiments, pneumococcal saccharides from serotypes 9V, 18C, 11A, 15B, 22F, and/or 33F of the invention are O-acetylated. In some embodiments, pneumococcal saccharides from serotypes 9V, 11A, 15B, 22F, and/or 33F of the invention are O-acetylated.

The purified polysaccharides described herein are chemically activated in order to obtain saccharides capable of interacting with a carrier protein. These pneumococcal conjugates are prepared by separate processes and formulated as a single dosage unit as described below.

1.2.1 Pneumococcal polysaccharide from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F

Capsular saccharides from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F can be prepared by standard procedures known to those skilled in the art (see, e.g., WO 2006/110381). Capsular polysaccharides can be obtained by growing each S. pneumoniae serotype in a medium; at the end of the growth cycle, the cells are lysed and the lysate broth is then collected for the isolation (purification) process. Individual polysaccharides are typically purified using centrifugation, precipitation, ultrafiltration, and/or column chromatography (see, for example, WO 2006/110352 and WO 2008/118752). Purified polysaccharides, in addition, can be further subjected to processing, as described in this document, to obtain glycoconjugates according to the invention.

In some embodiments, the purified polysaccharides from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and/or 23F have a molecular weight of 10 kDa to 4000 kDa before conjugation. . In other such embodiments, the polysaccharide has a molecular weight of 50 kDa to 4000 kDa; 50 kDa to 3000 kDa or 50 kDa to 2000 kDa. In further such embodiments, the polysaccharide has a molecular weight of 50 kDa to 3500 kDa; from 50 kDa to 3000 kDa; from 50 kDa to 2500 kDa; from 50 kDa to 2000 kDa; 50 kDa to 1750 kDa; from 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 100 kDa to 4000 kDa; from 100 kDa to 3500 kDa; from 100 kDa to 3000 kDa; from 100 kDa to 2500 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 1750 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 200 kDa to 4000 kDa; from 200 kDa to 3500 kDa; from 200 kDa to 3000 kDa; from 200 kDa to 2500 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1750 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The polysaccharide may become slightly smaller in size during conventional purification procedures. In addition, as described herein, the polysaccharide may be subjected to sizing procedures prior to conjugation. The molecular weight ranges indicated above refer to purified polysaccharides before conjugation (eg before activation) after an optional sizing step.

In some embodiments, pneumococcal saccharides from serotypes 9V and/or 18C of the invention are O-acetylated. In some embodiments, serotype 9V pneumococcal saccharide of the invention is O-acetylated and serotype 18C pneumococcal saccharide of the invention is de-O-acetylated.

1.2.2 Pneumococcal polysaccharide serotype 8

The serotype 8 polysaccharide repeat unit consists of a linear tetrasaccharide unit with one glucuronic acid (GlcpA), two glucopyranoses (Glcp), and one galactopyranose (Galp) (Jones et al. (1957) The Journal of the American Chemical Society. 79(11): 2787-2793). All four monosaccharides are linked via 1,4 bonds as shown in figure 1.

Serotype 8 saccharides can be obtained directly from bacteria using isolation procedures known to those skilled in the art (see, for example, the methods disclosed in US Patent Application Publication Nos. 0184072, 2007/0231340, and 2008/0102498 and WO 2008/118752). In addition, they can be obtained using synthetic protocols.

Serotype 8 S. pneumoniae strains can be obtained from established culture collections (such as, for example, the Streptococcal Reference Laboratory (Centers for Disease Control and Prevention, Atlanta, GA)) or clinical specimens. In some embodiments, the purified polysaccharides from S. pneumoniae serotype 8 have a molecular weight of 10 kDa to 2000 kDa prior to conjugation. In one embodiment, the capsular polysaccharide has a molecular weight of 50 kDa to 1000 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 70 kDa to 900 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 100 kDa to 800 kDa.

In the following embodiments, the capsular polysaccharide has a molecular weight of 100 kDa to 600 kDa; from 100 kDa to 500 kDa; from 100 kDa to 400 kDa; from 150 kDa to 600 kDa; from 150 kDa to 500 kDa; from 150 kDa to 400 kDa; from 200 kDa to 600 kDa; from 200 kDa to 500 kDa; from 200 kDa to 400 kDa; from 250 kDa to 600; from 250 kDa to 500 kDa; from 250 kDa to 400 kDa; from 250 kDa to 350 kDa; from 300 kDa to 600 kDa; from 300 kDa to 500 kDa; from 300 kDa to 400 kDa; from 400 kDa to 600 kDa; from 500 kDa to 600 kDa; and similar desired molecular weight ranges. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The polysaccharide may become slightly smaller in size during conventional purification procedures. In addition, as described herein, the polysaccharide may be subjected to sizing procedures prior to conjugation. The molecular weight ranges indicated above refer to purified polysaccharides before conjugation (eg before activation) after an optional sizing step.

1.2.3 Pneumococcal polysaccharide serotype 10A

The serotype 10A polysaccharide repeat unit consists of a branched hexasaccharide repeat unit with two galactofuranoses (Gal _f ), three galactopyranoses (Gal _p ), one N-acetylgalactosamine (Gal _p NAc), and skeletal phosphoribitol (Jones, C. 2005) Carbohydrate Research 269 (1 ): 175-181). There are two branched monosaccharides in the β-GalpNAc fragment (β-3-Galp and β-6-Galf) as shown in figure 2.

Serotype 10A saccharides can be obtained directly from bacteria using isolation procedures known to those skilled in the art (see, for example, methods disclosed in US Patent Application Publication Nos. 0184072, 2007/0231340, and 2008/0102498 and WO 2008/118752). In addition, they can be obtained using synthetic protocols.

S. pneumoniae serotype 10A strains can be obtained from established culture collections (such as, for example, the Streptococcal Reference Laboratory (Centers for Disease Control and Prevention, Atlanta, GA)) or clinical specimens. In some embodiments, the purified polysaccharides from S. pneumoniae serotype 10A have a molecular weight of 10 kDa to 2000 kDa prior to conjugation. In one embodiment, the capsular polysaccharide has a molecular weight of 50 kDa to 1000 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 70 kDa to 900 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 100 kDa to 800 kDa.

In the following embodiments, the capsular polysaccharide has a molecular weight of 100 kDa to 600 kDa; from 100 kDa to 500 kDa; from 100 kDa to 400 kDa; from 150 kDa to 600 kDa; from 150 kDa to 500 kDa; from 150 kDa to 400 kDa; from 200 kDa to 600 kDa; from 200 kDa to 500 kDa; from 200 kDa to 400 kDa; from 250 kDa to 600 kDa; from 250 kDa to 500 kDa; from 250 kDa to 400 kDa; from 250 kDa to 350 kDa; from 300 kDa to 600 kDa; from 300 kDa to 500 kDa; from 300 kDa to 400 kDa; from 400 kDa to 600 kDa; from 500 kDa to 600 kDa; and similar desired molecular weight ranges. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The polysaccharide may become slightly smaller in size during conventional purification procedures. In addition, as described herein, the polysaccharide may be subjected to sizing procedures prior to conjugation. The molecular weight ranges indicated above refer to purified polysaccharides before conjugation (eg before activation) after an optional sizing step.

1.2.4 Pneumococcal polysaccharide serotype 11A

The serotype 11A polysaccharide repeating unit consists of a linear tetrasaccharide backbone (two galactopyranoses (Gal _p ) and two glucopyranoses (Glc _p )) and a lateral phosphoglycerol (Richards et al. (1988) Adv. Exp. Med. Biol. 228: 595-597) , as shown in figure 3. The polysaccharide is O-acetylated at several locations and, based on the reported data described in the literature (Calix et al. (2011) J Bacteriol. 193 (19): 5271-5278), the total amount of O- acetylation at 11 polysaccharides is approximately 2.6 O-acetyl groups per polysaccharide repeating unit.

Serotype 11A saccharides can be obtained directly from bacteria using isolation procedures known to those skilled in the art (see, for example, the methods disclosed in US Patent Application Publication Nos. 0184072, 2007/0231340, and 2008/0102498 and WO 2008/118752). In addition, they can be obtained using synthetic protocols.

S. pneumoniae serotype 11A strains can be obtained from established culture collections (such as, for example, the Streptococcal Reference Laboratory (Centers for Disease Control and Prevention, Atlanta, GA)) or clinical specimens. An isolated serotype 11A capsular polysaccharide obtained by purifying the serotype 11 polysaccharide from a S. pneumoniae lysate and optionally sizing the purified polysaccharide can be characterized by various attributes, including, for example, molecular weight (M.W.) and mM acetate per mM of said capsular polysaccharide serotype 11A.

In some embodiments, the purified polysaccharides from S. pneumoniae serotype 11A have a molecular weight of 10 kDa to 2000 kDa prior to conjugation. In one embodiment, the capsular polysaccharide has a molecular weight of 50 kDa to 1000 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 70 kDa to 900 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 100 kDa to 800 kDa.

In the following embodiments, the capsular polysaccharide has a molecular weight of 100 kDa to 600 kDa; from 100 kDa to 500 kDa; from 100 kDa to 400 kDa; from 100 kDa to 300 kDa; from 100 kDa to 200 kDa; from 150 kDa to 600 kDa; from 150 kDa to 500 kDa; from 150 kDa to 400 kDa; from 150 kDa to 300 kDa; from 150 kDa to 200 kDa; from 200 kDa to 600 kDa; from 200 kDa to 500 kDa; from 200 kDa to 400 kDa; from 250 kDa to 600 kDa; from 250 kDa to 500 kDa; from 250 kDa to 400 kDa; from 250 kDa to 350 kDa; from 300 kDa to 600 kDa; from 300 kDa to 500 kDa; from 300 kDa to 400 kDa; from 400 kDa to 600 kDa; from 500 kDa to 600 kDa; and similar desired molecular weight ranges. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The polysaccharide may become slightly smaller in size during conventional purification procedures. In addition, as described herein, the polysaccharide may be subjected to sizing procedures prior to conjugation. The molecular weight ranges indicated above refer to purified polysaccharides before conjugation (eg before activation) after an optional sizing step.

In one embodiment, the size of the purified serotype 11 polysaccharide is reduced by high pressure homogenization. High pressure homogenization provides high shear rates by pumping the process stream through a relatively small flow path. The shear rate is increased by using a higher applied homogenization pressure and the dwell time can be increased by recycling the feed stream through the homogenizer.

The high pressure homogenization process is particularly suitable for reducing the size of the purified serotype 11 polysaccharide while retaining structural features of the polysaccharide such as the presence of O-acetyl groups.

The presence of O-acetyl in a purified, isolated, or activated serotype 11A capsular polysaccharide or in a serotype 11 polysaccharide-carrier protein conjugate is expressed as mM acetate per mM said polysaccharide, or as number of O-acetyl groups per polysaccharide repeating unit.

In a preferred embodiment, the purified polysaccharides from S. pneumoniae serotype 11A have at least 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, or 1.6 , µmol acetate per µmol of the indicated serotype 11A capsular polysaccharide.

1.2.5 Pneumococcal polysaccharide serotype 12F

The serotype 12F polysaccharide repeating unit consists of a linear trisaccharide backbone (one N-acetylfucosamine (Fuc _p NAc), one N-acetylgalactosamine (Gal _p NAc), and one N-acetylmannuronic acid (Man _p NAcA)) with two branches: a lateral α-galactopyranose (Gal _p ) linked at C3 Fuc _p NAc and α-Glc _p -(1→2)-α-Glc _p disaccharide branch linked at C3 Man _p NAcA (Leontein et al. (1983) Carbohydrate Research 114 (2) : 257-266.), as shown in figure 4.

Streptococcus pneumoniae serotype 12F strains can be obtained from established culture collections (such as, for example, the Streptococcal Reference Laboratory (Centers for Disease Control and Prevention, Atlanta, GA)) or clinical specimens.

Capsular saccharides from S. pneumoniae serotype 12F are prepared according to standard procedures known to those skilled in the art. Typically, capsular polysaccharides are obtained by growing each S. pneumoniae serotype in a medium (eg, soy-based medium), the polysaccharides are then obtained from a bacterial culture. A population of the organism (S. pneumoniae serotype 12F) is often scaled up from inoculum growth vials to inoculum growth flasks and passaged through one or more seed fermenters, increasing volume is achieved until increased fermentation volumes are obtained. At the end of the growth cycle, the cells are lysed and the lysate broth is then collected for a downstream processing (purification) process (see, for example, WO 2006/110381 and WO 2008/118752, U.S. Patent Application Publication Nos. 2006/0228380, 2006/0228381, 2008 /0102498 and US 2008/0286838). Polysaccharides are typically purified using centrifugation, precipitation, ultrafiltration and/or column chromatography (see, for example, WO 2006/110352 and WO 2008/118752).

Purified polysaccharides from serotype 12F can be activated (eg, chemically activated) to render them reactive and then incorporated into the glycoconjugates of the invention, as further described herein.

In some embodiments, the purified polysaccharides from S. pneumoniae serotype 12F have a molecular weight of 10 kDa to 2000 kDa prior to conjugation. In one embodiment, the capsular polysaccharide has a molecular weight of 50 kDa to 1000 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 50 kDa to 300 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 70 kDa to 300 kDa. In the following embodiments, the capsular polysaccharide has a molecular weight of 90 kDa to 250 kDa; from 90 kDa to 150 kDa; from 90 kDa to 120 kDa; from 80 kDa to 120 kDa; from 70 kDa to 100 kDa; from 70 kDa to 110 kDa; from 70 kDa to 120 kDa; from 70 kDa to 130 kDa; from 70 kDa to 140 kDa; from 70 kDa to 150 kDa; from 70 kDa to 160 kDa; from 80 kDa to 110 kDa; from 80 kDa to 120 kDa; from 80 kDa to 130 kDa; from 80 kDa to 140 kDa; from 80 kDa to 150 kDa; from 80 kDa to 160 kDa; from 90 kDa to 110 kDa; from 90 kDa to 120 kDa; from 90 kDa to 130 kDa; from 90 kDa to 140 kDa; from 90 kDa to 150 kDa; from 90 kDa to 160 kDa; from 100 kDa to 120 kDa; from 100 kDa to 130 kDa; from 100 kDa to 140 kDa; from 100 kDa to 150 kDa; from 100 kDa to 160 kDa; and similar desired molecular weight ranges. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The polysaccharide may become slightly smaller in size during conventional purification procedures. In addition, as described herein, the polysaccharide may be subjected to sizing procedures prior to conjugation. The molecular weight ranges indicated above refer to purified polysaccharides before conjugation (eg before activation) after an optional sizing step.

1.2.6 Pneumococcal polysaccharide serotype 15B

As shown in Figure 5, the serotype 15B polysaccharide repeating unit consists of a branched trisaccharide backbone (one N-acetylglucosamine (Glc _p NAc), one galactopyranose (Gal _p ), and one glucopyranose (Glc _p )) with an αGal _p -βGal _p disaccharide branch, associated with C4 hydroxyl group Glc _p NAc. Phosphoglycerol is linked to the C3 hydroxyl group of the βGal _p residue in the disaccharide branch (Jones et al. (2005) Carbohydrate Research 340 (3): 403-409). The capsular polysaccharide from serotype 15C has an identical backbone structure as serotype 15B, but does not contain O-acetylation.

Serotype 15B polysaccharides can be obtained directly from bacteria using isolation procedures known to those skilled in the art (see, for example, the methods disclosed in US Patent Application Publication Nos. 0184072, 2007/0231340, and 2008/0102498 and WO 2008/118752). They may also be prepared using synthetic protocols known to those skilled in the art.

S. pneumoniae serotype 15B strains can be obtained from established culture collections (such as, for example, American Type Culture Collection (ATCC, Manassas, VA USA) (e.g. deposit strain no. ATCC10354) or Streptococcal Reference Laboratory (Centers for Disease Control and Prevention , Atlanta, GA USA)) or from clinical specimens.

The bacterial cells are grown in a medium, preferably a soy-based medium. After fermentation of bacterial cells that produce S. pneumoniae serotype 15B capsular polysaccharides, the bacterial cells are lysed to obtain a cell lysate. The serotype 15B polysaccharide can then be isolated from the cell lysate using purification methods known in the art, including the use of centrifugation, depth filtration, sedimentation, ultrafiltration, activated charcoal treatment, diafiltration, and/or column chromatography (see, for example, U.S. patent application publications Nos. 2006/0228380, 2006/0228381, 2007/0184071, 2007/0184072, 2007/0231340, and 2008/0102498 and WO 2008/118752). The pure serotype 15B capsular polysaccharide can then be used to prepare immunogenic conjugates.

An isolated serotype 15B capsular polysaccharide obtained by purifying the serotype 15B polysaccharide from a S. pneumoniae lysate and optionally sizing the purified polysaccharide can be characterized using various parameters including, for example, molecular weight (M.W.), mM acetate per mM serotype 15B capsular polysaccharide assigned per mM glycerol per mM serotype 15B capsular polysaccharide assigned.

Preferably, in order to generate 15B conjugates with advantageous filterability characteristics and/or yields, sizing of the polysaccharide in the target molecular weight range is performed prior to conjugation to the carrier protein. Advantageously, the size of the purified serotype 15B polysaccharide is reduced while retaining critical structural features of the polysaccharide, such as, for example, the presence of O-acetyl groups. Preferably, the size of the purified serotype 15B polysaccharide is reduced by mechanical homogenization.

In a preferred embodiment, the size of the purified serotype 15B polysaccharide is reduced by high pressure homogenization. High pressure homogenization achieves high shear rates by pumping the process stream through a relatively small flow path. The shear rate is increased by using a higher applied homogenization pressure and the dwell time can be increased by recycling the feed stream through the homogenizer.

The high pressure homogenization process is particularly suitable for reducing the size of the purified serotype 15B polysaccharide while retaining structural features of the polysaccharide, such as the presence of O-acetyl groups.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 5 kDa to 500 kDa, 50 kDa to 500 kDa, 50 kDa to 450 kDa, 100 kDa to 400 kDa, and 100 kDa to 350 kDa. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 100 kDa to 350 kDa. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 100 kDa to 300 kDa. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 150 kDa to 300 kDa. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 150 kDa to 350 kDa. In the following embodiments, the capsular polysaccharide has a molecular weight of 100 kDa to 500 kDa; from 100 kDa to 400 kDa; from 100 kDa to 300 kDa; from 100 kDa to 200 kDa; from 150 kDa to 500 kDa; from 150 kDa to 400 kDa; from 150 kDa to 300 kDa; from 150 kDa to 200 kDa; from 200 kDa to 500 kDa; from 200 kDa to 400 kDa; from 250 kDa to 500 kDa; from 250 kDa to 400 kDa; from 250 kDa to 350 kDa; from 300 kDa to 500 kDa; from 300 kDa to 400 kDa; and similar desired molecular weight ranges. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The serotype 15B polysaccharide is O-acetylated and the total amount of O-acetylation is approximately 0.8-0.9 O-acetyl groups per polysaccharide repeating unit. The degree of O-acetylation of a polysaccharide can be determined using any method known in the art, such as using proton NMR (see, for example, Lemercinier et al. (1996) Carbohydrate Research 296: 83-96; Jones et al. (2002 ) J. Pharmaceutical and Biomedical Analysis 30: 1233-1247; WO 2005/033148 and WO 00/56357). Another commonly used method is described in Hestrin, S. (1949) J. Biol. Chem. 180:249-261. Preferably, the presence of O-acetyl groups is determined using ion-HPLC analysis.

The presence of O-acetyl in a purified, isolated, or activated serotype 15B capsular polysaccharide or in a serotype 15B-carrier protein conjugate polysaccharide is expressed as mM acetate per mM said polysaccharide or as O-acetyl groups per polysaccharide repeating unit.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 mM acetate per mm of the specified capsular polysaccharide serotype 15B. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.5, 0.6, or 0.7 mM acetate per mM of said serotype 15B capsular polysaccharide. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.7 mM acetate per mM of said serotype 15B capsular polysaccharide.

The presence of glycerophosphate side chains is determined by measuring glycerol using high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) after its release upon treatment of the polysaccharide with hydrofluoric acid (HF). The presence of glycerol in the purified, isolated, or activated serotype 15B polysaccharide or serotype 15B-carrier protein conjugate polysaccharide is expressed as mM glycerol per mM serotype 15B polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 mM glycerol per mm of the specified capsular polysaccharide serotype 15B. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.5, 0.6, or 0.7 mM glycerol per mM of said serotype 15B capsular polysaccharide. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.6 mM glycerol per mM of said serotype 15B capsular polysaccharide. In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.7 mM glycerol per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 100 kDa to 350 kDa and contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 100 kDa to 350 kDa and contains at least 0.6 mM glycerol per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 150 kDa to 300 kDa and contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 150 kDa to 300 kDa and contains at least 0.6 mM glycerol per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 150 kDa to 350 kDa and contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 150 kDa to 350 kDa and contains at least 0.6 mM glycerol per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide and at least 0.6 mM glycerol per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 100 kDa to 350 kDa and contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide and at least 0.6 mM glycerol per mm of the specified capsular polysaccharide serotype 15B.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 150 kDa to 300 kDa and contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide and at least 0.6 mM glycerol per mm of the specified capsular polysaccharide serotype 15B.

In a preferred embodiment, the isolated serotype 15B capsular polysaccharide has a molecular weight of 150 kDa to 350 kDa and contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide and at least 0.6 mM glycerol per mm of the specified capsular polysaccharide serotype 15B.

1.2.7 Pneumococcal polysaccharide serotype 22F

As shown in Figure 6, the serotype 22F polysaccharide repeating unit consists of a branched pentasaccharide backbone (one glucuronic acid (Glc _p A), one glucopyranose (Glc _p ), one galactofuranose (Gal _f ), and two rhamnopyranoses (Rha _p )) with αGlc _p a branch linked to the C3 hydroxyl group of βRha _p (Richards et al. (1989) Canadian Journal of Chemistry 67 (6): 1038-1050). Approximately 80% of the C2 hydroxyl groups of the βRha _p residue in the polysaccharide repeating unit are O-acetylated.

Serotype 22F polysaccharides can be obtained directly from bacteria using isolation procedures known to those skilled in the art (see, for example, the methods disclosed in US Patent Application Publications Nos. 0184072, 2007/0231340, and 2008/0102498 and WO 2008/118752). In addition, they can be obtained using synthetic protocols.

S. pneumoniae serotype 22F strains can be obtained from established culture collections (such as, for example, the Streptococcal Reference Laboratory (Centers for Disease Control and Prevention, Atlanta, GA)) or clinical specimens. An isolated serotype 22F capsular polysaccharide obtained by purifying the serotype 22F polysaccharide from a S. pneumoniae lysate and optionally sizing the purified polysaccharide can be characterized by various parameters including, for example, molecular weight (M.W.) and mM acetate per mM the specified capsular polysaccharide serotype 22F.

Preferably, in order to generate serotype 22F conjugates with advantageous filterability characteristics and/or yields, sizing of the polysaccharide in the target molecular weight range is performed prior to conjugation to the carrier protein. Advantageously, the size of the purified serotype 22F polysaccharide is reduced while retaining critical structural features of the polysaccharide, such as, for example, the presence of an O-acetyl group. Preferably, the size of the purified serotype 22F polysaccharide is reduced by mechanical homogenization.

In a preferred embodiment, the size of the purified polysaccharide is reduced by high pressure homogenization. High pressure homogenization achieves high shear rates by pumping the process stream through a relatively small flow path. The shear rate is increased by using a higher applied homogenization pressure and the dwell time can be increased by recycling the feed stream through the homogenizer.

The high pressure homogenization process is particularly suitable for reducing the size of the purified serotype 22F polysaccharide while retaining structural features of the polysaccharide, such as the presence of O-acetyl groups.

In some embodiments, the purified polysaccharides from S. pneumoniae serotype 22F have a molecular weight of 10 kDa to 2000 kDa prior to conjugation. In one embodiment, the capsular polysaccharide has a molecular weight of 50 kDa to 1000 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 70 kDa to 900 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 100 kDa to 800 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 200 kDa to 600 kDa. In another embodiment, the capsular polysaccharide has a molecular weight of 400 kDa to 700 kDa.

In the following embodiments, the capsular polysaccharide has a molecular weight of 100 kDa to 1000 kDa; from 100 kDa to 900 kDa; from 100 kDa to 800 kDa; from 100 kDa to 700 kDa; from 100 kDa to 600 kDa; from 100 kDa to 500 kDa; from 100 kDa to 400 kDa; from 100 kDa to 300 kDa; from 150 kDa to 1000 kDa; from 150 kDa to 900 kDa; from 150 kDa to 800 kDa; from 150 kDa to 700 kDa; from 150 kDa to 600 kDa; from 150 kDa to 500 kDa; from 150 kDa to 400 kDa; from 150 kDa to 300 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 900 kDa; from 200 kDa to 800 kDa; from 200 kDa to 700 kDa; from 200 kDa to 600 kDa; from 200 kDa to 500 kDa; from 200 kDa to 400 kDa; from 200 kDa to 300 kDa; from 250 kDa to 1000 kDa; from 250 kDa to 900 kDa; from 250 kDa to 800 kDa; from 250 kDa to 700 kDa; from 250 kDa to 600 kDa; from 250 kDa to 500 kDa; from 250 kDa to 400 kDa; from 250 kDa to 350 kDa; from 300 kDa to 1000 kDa; from 300 kDa to 900 kDa; from 300 kDa to 800 kDa; from 300 kDa to 700 kDa; from 300 kDa to 600 kDa; from 300 kDa to 500 kDa; from 300 kDa to 400 kDa; from 400 kDa to 1000 kDa; from 400 kDa to 900 kDa; from 400 kDa to 800 kDa; from 400 kDa to 700 kDa; from 400 kDa to 600 kDa; from 500 kDa to 600 kDa; and similar desired molecular weight ranges. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The polysaccharide may become slightly smaller in size during conventional purification procedures. In addition, as described above herein, the 22F polysaccharide may be subjected to sizing procedures prior to conjugation. The molecular weight ranges indicated above refer to purified polysaccharides before conjugation (eg before activation) after an optional sizing step. The degree of O-acetylation of a polysaccharide can be determined using any method known in the art, for example, using proton NMR (Lemercinier et al. (1996) Carbohydrate Research 296: 83-96; Jones et al. (2002) J. Pharmaceutical and Biomedical Analysis 30: 1233-1247; WO 2005/033148 and WO 00/56357). Another commonly used method is described in Hestrin, S. (1949) J. Biol. Chem. 180:249-261. Preferably, the presence of O-acetyl groups is determined using ion-HPLC analysis.

The presence of O-acetyl in a purified, isolated, or activated serotype 22F capsular polysaccharide or in a serotype 22F polysaccharide-carrier protein conjugate is expressed as mM acetate per mM said polysaccharide or as number of O-acetyl groups per polysaccharide repeating unit.

In a preferred embodiment, the purified polysaccharides from S. pneumoniae serotype 22F has at least 0.2, 0.4, 0.6, 0.8.1, 1.2, 1.4, or 1.6 µmol acetate per µmol of said serotype 22F capsular polysaccharide.

1.2.8 Pneumococcal polysaccharide serotype 33F

As shown in Figure 7, the polysaccharide repeating unit of serotype 33F consists of a branched pentasaccharide backbone (two galactopyranoses (Gal _p ), two galactofuranoses (Gal _f ), and one glucopyranose (Glc _p ) with a terminal αGal _p linked to the C2 hydroxyl group of the residue αGal _p within the backbone (Lemercinier et al. (2006) Carbohydrate Research 341 (1): 68-74.) It has been reported in the literature that the C2 hydroxyl group of the backbone of the 3-β-Gal _f residue is O-acetylated.

Serotype 33F polysaccharides can be obtained directly from bacteria using isolation procedures known to those skilled in the art (see, for example, the methods disclosed in US Patent Application Publications Nos. 0184072, 2007/0231340, and 2008/0102498 and WO 2008/118752). In addition, they can be obtained using synthetic protocols.

S. pneumoniae serotype 33F strains can be obtained from established culture collections (such as, for example, the Streptococcal Reference Laboratory (Centers for Disease Control and Prevention, Atlanta, GA)) or clinical specimens. Purified polysaccharides from serotype 33F can be activated (eg, chemically activated) to render them reactive and then incorporated into glycoconjugates of the invention, as further described herein.

An isolated serotype 33F capsular polysaccharide obtained by purifying the serotype 33F polysaccharide from a S. pneumoniae lysate and optionally sizing the purified polysaccharide can be characterized using various parameters, including, for example, molecular weight and mM acetate per mM of the indicated serotype capsular polysaccharide 33F.

In some embodiments, the purified polysaccharides from S. pneumoniae serotype 33F have a molecular weight of 10 kDa to 2000 kDa prior to conjugation. In other such embodiments, the saccharide has a molecular weight of 50 kDa to 2000 kDa. In further such embodiments, the saccharide has a molecular weight of 50 kDa to 1750 kDa; from 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 1750 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1750 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

The polysaccharide may become slightly smaller in size during conventional purification procedures. In addition, as described herein, the polysaccharide may be subjected to sizing procedures prior to conjugation. The molecular weight ranges indicated above refer to purified polysaccharides before conjugation (eg before activation) after an optional sizing step.

The presence of O-acetyl in a purified, isolated, or activated serotype 33F capsular polysaccharide or in a serotype 33F polysaccharide-carrier protein conjugate is expressed as mM acetate per mM said polysaccharide or as number of O-acetyl groups per polysaccharide repeating unit.

In a preferred embodiment, the purified polysaccharides from S. pneumoniae serotype 33F has at least 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, or 1.6 , µmol acetate per µmol of the indicated serotype 33F capsular polysaccharide.

1.3 Glycoconjugates according to the invention

The purified saccharides are chemically activated to make the saccharides (ie, activated saccharides) reactive with the carrier protein. Once activated, each capsular saccharide is separately conjugated to a carrier protein in order to obtain a glycoconjugate. In one embodiment, each capsular saccharide is conjugated to the same carrier protein. Chemical activation of saccharides and subsequent conjugation to a carrier protein can be achieved using the activation and conjugation methods disclosed herein.

1.3.1. Glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F

Capsular polysaccharides from S. Pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F are prepared according to standard procedures known to those skilled in the art (see e.g. WO 2006 /110381, WO 2008/118752, WO 2006/110352, and U.S. Patent Application Publication Nos.

In one embodiment, the polysaccharides are activated with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) to form a cyanate ester. The activated polysaccharide is then coupled directly or via a spacer (linker) group to an amino group on the carrier protein (preferably CRM ₁₉₇ ). For example, the spacer may be a cystamine or cysteamine to provide a thiolated polysaccharide which may be coupled to the carrier via a thioether bond formed after reaction with a maleimide-activated carrier protein (e.g. using N-[γ-maleimidobutyryloxy]succinimide complex ether (GMBS)) or haloacetylated carrier protein (e.g. using iodoacetamide, N-succinimidyl bromoacetate (SBA; SIB), N-succinimidyl(4-iodoacetyl)aminobenzoate (SIAB), sulfosuccinimidyl(4-iodoacetyl)aminobenzoate (sulfo-SIAB ), N-succinimidyl iodoacetate (SIA) or succinimidyl 3-[bromoacetamido]propionate (SBAP)). Preferably, the cyanate ester (optionally prepared using CDAP chemistry) is coupled with hexanediamine or adipic acid hydrazide (ADH) and the amino-derivatized saccharide is conjugated to a carrier protein (e.g., CRM ₁₉₇ ) using a carbodiimide (e.g., EDAC or EDC ) chemistry through a carboxyl group on a protein carrier. Such conjugates are described, for example, in WO 93/15760, WO 95/08348 and WO 96/129094.

Other suitable conjugation methods use carbodiimides, hydrazides, active esters, norborane, p-nitrobenzoic acid, N-hydroxysuccinimide, S-NHS, EDC, TSTU. Many of these are described in International Patent Publication No. WO 98/42721. The conjugation may include a carbonyl linker which may be formed by the reaction of the free hydroxyl group of the saccharide with 1,1'-carbonyldiimidazole (CDI) (see Bethell et al. (1979) J. Biol. Chern. 254: 2572-2574; Hearn et al (1981) J. Chromatogr. 218: 509-518) followed by reaction with the protein to form a carbamate bond. This may include reducing the anomeric end to a primary hydroxyl group, optionally protecting/deprotecting the primary hydroxyl group, reacting the primary hydroxyl group with a CDI to form a CDI carbamate intermediate, and reacting a CDI carbamate intermediate with an amino group on a protein.

In a preferred embodiment, at least one of the capsular polysaccharides from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F are conjugated to a carrier protein via reductive amination (such as described in US Patent Application Publication Nos. 2006/0228380, 2007/0231340, 2007/0184071 and 2007/0184072, WO 2006/110381, WO 2008/079653, and WO 2008/143709). In a preferred embodiment, the capsular polysaccharides from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F are all conjugated to a carrier protein via reductive amination.

Reductive amination involves two steps, (1) oxidation of the polysaccharide, (2) reduction of the activated polysaccharide and carrier protein to form a conjugate. Before oxidation, the polysaccharide is optionally hydrolysed. Mechanical or chemical hydrolysis may be used. Chemical hydrolysis can be carried out using acetic acid. The oxidation step may include reaction with periodate. For the purposes of the present invention, the term "periodate" includes both periodate and periodic acid; the term also includes both metaperiodate (IO ₄ ^- ) and orthoperiodate (IO ₆ ^5- ) and various periodate salts (eg, sodium periodate and potassium periodate).

In one embodiment, a capsular polysaccharide from serotype 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, or 23F from S. pneumoniae is oxidized in the presence of metaperiodate, preferably in the presence of sodium periodate (NaIO ₄ ). In another embodiment, the capsular polysaccharide from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F is oxidized in the presence of orthoperiodate, preferably in the presence of periodic acid.

After the polysaccharide oxidation step, the polysaccharide is said to be activated and referred to as "activated polysaccharide" herein below. The activated polysaccharide and carrier protein may be lyophilized (freeze-dried) or independently (lyophilized separately) or together (co-lyophilized). In one embodiment, the activated polysaccharide and carrier protein are co-lyophilized. In another embodiment, the activated polysaccharide and carrier protein are lyophilized independently of each other.

In one embodiment, lyophilization occurs in the presence of a non-reducing sugar, possibly non-reducing sugars include sucrose, trehalose, raffinose, stachyose, melecytose, dextran, mannitol, lactitol, and palatinite.

The second step of the conjugation process is the reduction of the activated polysaccharide and carrier protein to form a conjugate (so-called reductive amination), using a reducing agent. Reducing agents that are suitable include cyanoborohydrides such as sodium cyanoborohydride, borane pyridine, or borohydride exchange resin. In one embodiment, the reducing agent is sodium cyanoborohydride.

In one embodiment, the reduction reaction is carried out in an aqueous solvent, in another embodiment, the reaction is carried out in an aprotic solvent. In one embodiment, the reduction reaction is carried out in DMSO (dimethyl sulfoxide) or DMF (dimethylformamide) solvent. A DMSO or DMF solvent can be used to reconstitute the activated polysaccharide and the carrier protein that has been lyophilized.

At the end of the reduction reaction, unreacted aldehyde groups may remain in the conjugates and may be blocked with a suitable blocking agent. In one embodiment, this blocking agent is sodium borohydride (NaBH ₄ ). After conjugation (reduction reaction and optionally blocking), the glycoconjugates can be purified. Glycoconjugates can be purified by diafiltration and/or ion exchange chromatography and/or gel permeation chromatography. In one embodiment, the glycoconjugates are purified using diafiltration or ion exchange chromatography or gel permeation chromatography. In one embodiment, the glycoconjugates are subjected to sterilizing filtration.

In some embodiments, the glycoconjugate from S. pneumoniae serotypes 9V and/or 18C contains a saccharide that has a degree of O-acetylation from 10% to 100%, from 20% to 100%, from 30% to 100%, from 40% to 100%, 50% to 100%, 60% to 100%, 70% to 100%, 75% to 100%, 80% to 100%, 90% to 100%, 50% to 90 %, 60% to 90%, 70% to 90%, or 80% to 90%. In other embodiments, the degree of O-acetylation is ≥10%, ≥20%, ≥30%, ≥40%, ≥50%, ≥60%, ≥70%, ≥80%, or ≥90%, or about 100 %.

In some embodiments, the S. pneumoniae serotype 9V and/or 18C glycoconjugate of the invention is O-acetylated. In some embodiments, the S. pneumoniae serotype 9V glycoconjugate is O-acetylated and the S. pneumoniae serotype 18C glycoconjugate is de-O-acetylated.

1.3.2 Glycoconjugates from S. pneumoniae serotype 22F

In one embodiment, serotype 22F glycoconjugates are prepared by activating the polysaccharide with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) to form a cyanate ester. The activated polysaccharide can be attached directly or through a spacer (linker) group to the amino group on the carrier protein. For example, the spacer can be a cystamine or cysteamine, yielding a thiolated polysaccharide that can be attached to the carrier via a thioether bond formed after reaction with a maleimide-activated carrier protein (e.g., using GMBS) or a haloacetylated carrier protein (e.g., using iodoacetamide, SIB, SIAB, sulfo-SIAB, SIA, or SBAP). Preferably, the cyanate ester (optionally prepared using CDAP chemistry) is coupled with hexanediamine or adipic acid hydrazide (ADH) and the amino-derivatized saccharide is conjugated to the carrier protein using carbodiimide (e.g., EDAC or EDC) chemistry through the carboxyl group on the protein. carrier. Such conjugates are described, for example, in WO 93/15760, WO 95/08348 and WO 96/129094.

Other suitable methods use carbodiimides, hydrazides, active esters, norborane, p-nitrobenzoic acid, N-hydroxysuccinimide, S-NHS, EDC, TSTU. Many of these are described in International Patent Application Publication No. WO 98/42721. The conjugation may include a carbonyl linker which may be formed by the reaction of the free hydroxyl group of the saccharide with CDI (see Bethell et al. (1979) J. Biol. Chern. 254: 2572-2574; Hearn et al. (1981) J. Chromatogr 218: 509-518), followed by reaction with the protein to form a carbamate bond. This may include reducing the anomeric end to a primary hydroxyl group, optionally protecting/deprotecting the primary hydroxyl group, reacting the primary hydroxyl group with a CDI to form a CDI carbamate intermediate, and reacting a CDI carbamate intermediate with an amino group on a protein.

In preferred embodiments, the serotype 22F glycoconjugates of the invention are prepared using reductive amination. Reductive amination involves two steps, (1) oxidation of the polysaccharide to form aldehyde functional groups from vicinal diols in the individual hexasaccharide unit, (2) reduction of the activated polysaccharide and carrier protein (eg CRM ₁₉₇ ) to form a conjugate.

Preferably, the serotype 22F polysaccharide is sized within the target molecular weight (MW) range prior to oxidation. Advantageously, the size of the purified serotype 22F polysaccharide is reduced while retaining critical structural features of the polysaccharide, such as, for example, the presence of O-acetyl groups. Preferably, the size of the purified serotype 22F polysaccharide is reduced using mechanical homogenization (see section 1.2.7 above).

In one embodiment, the polysaccharide serotype is activated (oxidized) according to a method comprising the step of:

(a) reacting the isolated serotype 22F polysaccharide with an oxidizing agent;

(b) quenching the oxidative reaction by adding a quenching agent, resulting in an activated serotype 22F polysaccharide.

In a preferred embodiment, the oxidizing agent is a periodate. For the purposes of the present invention, the term "periodate" includes both periodate and periodic acid; the term also includes both metaperiodate (IO ₄ ^- ) and orthoperiodate (IO ₆ ^5- ) and various periodate salts (eg, sodium periodate and potassium periodate). In a preferred embodiment, the oxidizing agent is sodium periodate. In a preferred embodiment, the periodate used to oxidize the serotype 22F polysaccharide is metaperiodate. In a preferred embodiment, the periodate used to oxidize the serotype 22F polysaccharide is sodium metaperiodate.

In one embodiment, the quenching agent is selected from vicinal diols, 1,2-amino alcohols, amino acids, glutathione, sulfite, bisulfate, dithionite, metabisulfite, thiosulfate, phosphites, hypophosphites, or phosphorous acid.

In one embodiment, the quenching agent is 1,2-amino alcohols of formula (I):

where R ¹ is selected from H, methyl, ethyl, propyl or isopropyl.

In one embodiment, the quenching agent is selected from sodium and potassium salts of sulfite, bisulfate, dithionite, metabisulfite, thiosulfate, phosphites, hypophosphites, or salts of phosphorous acid.

In one embodiment, the quenching agent is an amino acid. In such embodiments, said amino acid may be selected from serine, threonine, cysteine, cystine, methionine, proline, hydroxyproline, tryptophan, tyrosine, and histidine.

In one embodiment, the quenching agent is a sulfite such as bisulfate, dithionite, metabisulfite, thiosulfate.

In one embodiment, the quenching agent is a compound containing two vicinal hydroxyl groups (vicinal diols), that is, two hydroxyl groups covalently bonded to two adjacent carbon atoms.

Preferably, the quenching agent is a compound of formula (II):

in which each R ¹ and R ² is independently selected from H, methyl, ethyl, propyl or isopropyl.

In a preferred embodiment, the quenching agent is glycerol, ethylene glycol, propane-1,2-diol, butane-1,2-diol or butane-2,3-diol, or ascorbic acid. In a preferred embodiment, the quenching agent is butane-2,3-diol.

In a preferred embodiment, the isolated serotype 22F polysaccharide is activated according to a method comprising the step of:

(a) interactions of the isolated polysaccharide serotype 22F with periodate;

(b) quenching the oxidative reaction by adding butane-2,3-diol, resulting in activated serotype 22F polysaccharide.

After the step of oxidizing the polysaccharide, the polysaccharide is said to be activated and referred to hereinafter as "activated polysaccharide".

In a preferred embodiment, the activated serotype 22F polysaccharide is purified. Activated serotype 22F polysaccharide is purified according to methods known to those skilled in the art such as gel permeation chromatography (GPC), dialysis, or ultrafiltration/diafiltration. For example, activated 22F polysaccharide is purified by concentration and diafiltration using an ultrafiltration device.

In a preferred embodiment, the oxidation state of the activated serotype 22F polysaccharide is 2 to 30, 2 to 25, 2 to 20, 2 to 15, 2 to 10, 2 to 5, 5 to 30, 5 to 25 , 5 to 20, 5 to 15, 5 to 10, 10 to 30, 10 to 25, 10 to 20, 10 to 15, 15 to 30, 15 to 25, 15 to 20 , 20 to 30, or 20 to 25. In a preferred embodiment, the oxidation state of the activated serotype 22F polysaccharide is 2 to 10, 4 to 8, 4 to 6, 6 to 8, 6 to 12, 8 to 14, 9 to 11, 10 to 16, 12 to 16, 14 to 18, 16 to 20, 16 to 18, 18 to 22, or 18 to 20.

In a preferred embodiment, the activated serotype 22F polysaccharide has a molecular weight of 25 kDa to 1000 kDa, 100 kDa to 1000 kDa, 300 kDa to 800 kDa, 300 kDa to 700 kDa, 300 kDa to 600 kDa, 400 kDa up to 1000 kDa, 400 kDa to 800 kDa, 400 kDa to 700 kDa, or 400 kDa to 600 kDa. In one embodiment, the activated serotype 22F polysaccharide has a molecular weight of 300 kDa to 800 kDa. In one embodiment, the activated serotype 22F polysaccharide has a molecular weight of 400 kDa to 600 kDa. In a preferred embodiment, the activated serotype 22F polysaccharide has a molecular weight of 400 kDa to 600 kDa, and an oxidation state of 10 to 25, 10 to 20, 12 to 20, or 14 to 18. In a preferred embodiment, the activated serotype polysaccharide 22F has a molecular weight of 400 kDa to 600 kDa and an oxidation state of 10 to 20.

In a preferred embodiment, the activated serotype 22F polysaccharide contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, or 0.7 or about 0.8 mM acetate per mM polysaccharide serotype 22F. In a preferred embodiment, the activated serotype 22F polysaccharide contains at least 0.5, 0.6, or 0.7 mM acetate per mM serotype 22F polysaccharide. In a preferred embodiment, the activated serotype 22F polysaccharide contains at least 0.6 mM acetate per mM serotype 22F polysaccharide.

In a preferred embodiment, the activated serotype 22F polysaccharide contains at least 0.7 mM acetate per mM serotype 22F polysaccharide. In a preferred embodiment, the activated serotype 22F polysaccharide has a molecular weight of 400 kDa to 800 kDa and contains at least 0.6 mM acetate per mM serotype 22F polysaccharide.

In a preferred embodiment, the activated serotype 22F polysaccharide has a molecular weight of 400 kDa to 800 kDa, an oxidation state of 12 to 20, and contains at least 0.6 mM acetate per mM serotype 22F polysaccharide.

The activated polysaccharide and/or carrier protein may be lyophilized (freeze-dried), either independently (lyophilized separately) or together (co-lyophilized).

In one embodiment, the activated serotype 22F polysaccharide is lyophilized, optionally in the presence of the saccharide. In a preferred embodiment, the saccharide is selected from sucrose, trehalose, raffinose, stachyose, melecytose, dextran, mannitol, lactitol and palatinite. In a preferred embodiment, the saccharide is sucrose. In one embodiment, the lyophilized activated polysaccharide is then mixed with a solution containing a carrier protein.

In another embodiment, the activated polysaccharide and carrier protein are co-lyophilized. In such embodiments, the activated serotype 22F polysaccharide is mixed with a carrier protein and optionally lyophilized in the presence of the saccharide. In a preferred embodiment, the saccharide is selected from sucrose, trehalose, raffinose, stachyose, melecytose, dextran, mannitol, lactitol and palatinite. In a preferred embodiment, the saccharide is sucrose. The co-lyophilized polysaccharide and carrier protein can then be resuspended in solution and reacted with a reducing agent.

The second step of the conjugation process is the reduction of the activated polysaccharide and carrier protein to form a conjugate (reductive amination) using a reducing agent.

The activated serotype 22F polysaccharide may be conjugated to a carrier protein according to a method comprising the step of:

(c) mixing the activated serotype 22F polysaccharide with a carrier protein; and

(d) reacting the compounded activated serotype 22F polysaccharide and carrier protein with a reducing agent to form a serotype 22F polysaccharide-carrier protein conjugate.

In one embodiment, the reduction reaction is carried out in an aqueous solvent, in another embodiment, the reaction is carried out in an aprotic solvent. In one embodiment, the reduction reaction is carried out in a DMSO (dimethyl sulfoxide) or DMF (dimethylformamide)) solvent. A DMSO or DMF solvent can be used to reconstitute the activated polysaccharide and the carrier protein that has been lyophilized.

Conjugation of an activated serotype 22F polysaccharide to a carrier protein by reductive amination in dimethyl sulfoxide (DMSO) is acceptable to maintain the O-acetyl content of the polysaccharide, compared to, for example, reductive amination in an aqueous phase, where the level of O-acetylation of the polysaccharide can be significantly reduced. Therefore, in a preferred embodiment, step (c) and step (d) are carried out in DMSO.

In one embodiment, the reducing agent is sodium cyanoborohydride, sodium triacetoxyborohydride, sodium or zinc borohydride in the presence of Bronsted or Lewis acids, aminoboranes such as pyridine-borane, 2-picoline-borane, 2,6-diborane-methanol, dimethylamine- borane, t-BuMe ⁱ PrN-BH ₃ , benzylamine-BH ₃ or 5-ethyl-2-methylpyridine-borane (PEMB). In a preferred embodiment, the reducing agent is sodium cyanoborohydride.

At the end of the reduction reaction, unreacted aldehyde groups may remain in the conjugates and may be blocked with a suitable blocking agent. In one embodiment, this blocking agent is sodium borohydride (NaBH ₄ ).

After the serotype 22F polysaccharide has been conjugated to a carrier protein, the glycoconjugate can be purified (enriched relative to the amount of polysaccharide-protein conjugate) using a variety of methods known to the skilled artisan. These methods include dialysis, concentration/diafiltration operations, tangential flow filtration, precipitation/elution, column chromatography (DEAE or hydrophobic interaction chromatography), and depth filtration.

In some embodiments, the serotype 22F glycoconjugates of the present invention comprise a saccharide having a molecular weight of 10 kDa to 2000 kDa. In other such embodiments, the saccharide has a molecular weight of 50 kDa to 1000 kDa. In other such embodiments, the saccharide has a molecular weight of 70 kDa to 900 kDa. In other such embodiments, the saccharide has a molecular weight of 100 kDa to 800 kDa. In other such embodiments, the saccharide has a molecular weight of 200 kDa to 600 kDa. In further such embodiments, the saccharide has a molecular weight of 100 kDa to 1000 kDa; from 100 kDa to 900 kDa; from 100 kDa to 800 kDa; from 100 kDa to 700 kDa; from 100 kDa to 600 kDa; from 100 kDa to 500 kDa; from 100 kDa to 400 kDa; from 100 kDa to 300 kDa; from 150 kDa to 1000 kDa; from 150 kDa to 900 kDa; from 150 kDa to 800 kDa; from 150 kDa to 700 kDa; from 150 kDa to 600 kDa; from 150 kDa to 500 kDa; from 150 kDa to 400 kDa; from 150 kDa to 300 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 900 kDa; from 200 kDa to 800 kDa; from 200 kDa to 700 kDa; from 200 kDa to 600 kDa; from 200 kDa to 500 kDa; from 200 kDa to 400 kDa; from 200 kDa to 300 kDa; from 250 kDa to 1000 kDa; from 250 kDa to 900 kDa; from 250 kDa to 800 kDa; from 250 kDa to 700 kDa; from 250 kDa to 600 kDa; from 250 kDa to 500 kDa; from 250 kDa to 400 kDa; from 250 kDa to 350 kDa; from 300 kDa to 1000 kDa; from 300 kDa to 900 kDa; from 300 kDa to 800 kDa; from 300 kDa to 700 kDa; from 300 kDa to 600 kDa; from 300 kDa to 500 kDa; from 300 kDa to 400 kDa; from 400 kDa to 1000 kDa; from 400 kDa to 900 kDa; from 400 kDa to 800 kDa; from 400 kDa to 700 kDa; from 400 kDa to 600 kDa; from 500 kDa to 600 kDa. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention. In some such embodiments, serotype 22F glycoconjugates are prepared using reductive amination.

In some embodiments, the serotype 22F glycoconjugate of the invention has a molecular weight of 400 kDa to 15,000 kDa; from 500 kDa to 10,000 kDa; from 2000 kDa to 10,000 kDa; from 3000 kDa to 8,000 kDa; or from 3000 kDa to 5,000 kDa. In other embodiments, the serotype 22F glycoconjugate has a molecular weight of 500 kDa to 10,000 kDa. In other embodiments, the serotype 22F glycoconjugate has a molecular weight of 1000 kDa to 8000 kDa. In yet other embodiments, the serotype 22F glycoconjugate has a molecular weight of 2000 kDa to 8000 kDa, or 3000 kDa to 7000 kDa. In further embodiments, the serotype 22F glycoconjugate of the invention has a molecular weight of 200 kDa to 20,000 kDa; from 200 kDa to 15000 kDa; from 200 kDa to 10,000 kDa; from 200 kDa to 7500 kDa; from 200 kDa to 5000 kDa; from 200 kDa to 3000 kDa; from 200 kDa to 1000 kDa; from 500 kDa to 20,000 kDa; from 500 kDa to 15000 kDa; from 500 kDa to 12500 kDa; from 500 kDa to 10,000 kDa; from 500 kDa to 7500 kDa; from 500 kDa to 6000 kDa; from 500 kDa to 5000 kDa; from 500 kDa to 4000 kDa; from 500 kDa to 3000 kDa; from 500 kDa to 2000 kDa; from 500 kDa to 1500 kDa; from 500 kDa to 1000 kDa; from 750 kDa to 20,000 kDa; from 750 kDa to 15000 kDa; from 750 kDa to 12500 kDa; from 750 kDa to 10,000 kDa; from 750 kDa to 7500 kDa; from 750 kDa to 6000 kDa; from 750 kDa to 5000 kDa; from 750 kDa to 4000 kDa; from 750 kDa to 3000 kDa; from 750 kDa to 2000 kDa; from 750 kDa to 1500 kDa; from 1000 kDa to 15000 kDa; from 1000 kDa to 12500 kDa; from 1000 kDa to 10000 kDa; from 1000 kDa to 7500 kDa; from 1000 kDa to 6000 kDa; from 1000 kDa to 5000 kDa; from 1000 kDa to 4000 kDa; from 1000 kDa to 2500 kDa; from 2000 kDa to 15000 kDa; from 2000 kDa to 12500 kDa; from 2000 kDa to 10000 kDa; from 2000 kDa to 7500 kDa; from 2000 kDa to 6000 kDa; from 2000 kDa to 5000 kDa; from 2000 kDa to 4000 kDa; or from 2000 kDa to 3000 kDa.

In further embodiments, the serotype 22F glycoconjugate according to the invention has a molecular weight of 3,000 kDa to 20,000 kDa; from 3000 kDa to 15000 kDa; from 3000 kDa to 10000 kDa; from 3000 kDa to 7500 kDa; from 3000 kDa to 5000 kDa; from 4000 kDa to 20000 kDa; from 4000 kDa to 15000 kDa; from 4000 kDa to 12500 kDa; from 4000 kDa to 10000 kDa; from 4000 kDa to 7500 kDa; from 4000 kDa to 6000 kDa; or from 4000 kDa to 5000 kDa.

In further embodiments, the serotype 22F glycoconjugate of the invention has a molecular weight of 5000 kDa to 20000 kDa; from 5000 kDa to 15000 kDa; from 5000 kDa to 10000 kDa; from 5000 kDa to 7500 kDa; from 6000 kDa to 20000 kDa; from 6000 kDa to 15000 kDa; from 6000 kDa to 12500 kDa; 6000 kDa to 10000 kDa or 6000 kDa to 7500 kDa.

The molecular weight of the glycoconjugate is measured using SEC-MALLS. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

In a preferred embodiment, the serotype 22F glycoconjugate of the invention contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, or 0.7 or about 0.8 mM acetate mM polysaccharide serotype 22F. In a preferred embodiment, the glycoconjugate contains at least 0.5, 0.6, or 0.7 mM acetate per mM serotype 22F polysaccharide. In a preferred embodiment, the glycoconjugate contains at least 0.6 mM acetate per mM serotype 22F polysaccharide. In a preferred embodiment, the glycoconjugate contains at least 0.7 mM acetate per mM serotype 22F polysaccharide.

In a preferred embodiment, the ratio of mM acetate per mM serotype 22F polysaccharide in the glycoconjugate to mM acetate per mM serotype 22F polysaccharide in the isolated polysaccharide is at least 0.6, 0.65, 0.7, 0.75, 0, 8, 0.85, 0.9 or 0.95. In a preferred embodiment, the ratio of mM acetate per mM serotype 22F polysaccharide in the glycoconjugate to mM acetate per mM serotype 22F polysaccharide in the isolated polysaccharide is at least 0.7. In a preferred embodiment, the ratio of mM acetate per mM serotype 22F polysaccharide in the glycoconjugate to mM acetate per mM serotype 22F polysaccharide in the isolated polysaccharide is at least 0.9.

In a preferred embodiment, the ratio of mM acetate per mM serotype 22F polysaccharide in the glycoconjugate to mM acetate per mM serotype 22F polysaccharide in the activated polysaccharide is at least 0.6, 0.65, 0.7, 0.75, 0, 8, 0.85, 0.9, or 0.95. In a preferred embodiment, the ratio of mM acetate per mM serotype 22F polysaccharide in the glycoconjugate to mM acetate per mM serotype 22F polysaccharide in the activated polysaccharide is at least 0.7. In a preferred embodiment, the ratio of mM acetate per mM serotype 22F polysaccharide in the glycoconjugate to mM acetate per mM serotype 22F polysaccharide in the activated polysaccharide is at least 0.9. Another way to characterize serotype 22F glycoconjugates of the invention is the number of lysine residues in the carrier protein (eg CRM ₁₉₇ ) that become conjugated to the saccharide, which can be characterized as a range of conjugated lysines (degree of conjugation). Evidence of a lysine modification of the carrier protein, due to covalent bonds with polysaccharides, can be obtained by amino acid analysis using standard methods known to those skilled in the art. The conjugation results in a reduction in the amount of lysine residues recovered compared to the original CRM ₁₉₇ protein material used to form the conjugate materials. In a preferred embodiment, the degree of conjugation of the serotype 22F glycoconjugate of the invention is 2 to 15, 2 to 13, 2 to 10, 2 to 8, 2 to 6, 2 to 5, 2 to 4, 3 to 15, 3 to 13, 3 to 10, 3 to 8, 3 to 6, 3 to 5, 3 to 4, 5 to 15, 5 to 10, 8 to 15, 8 up to 12, 10 to 15, or 10 to 12. In one embodiment, the degree of conjugation of the serotype 22F glycoconjugate of the invention is about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, or about 15. In a preferred embodiment, the degree of conjugation of the serotype 22F glycoconjugate of the invention is 4 to 7. In some such embodiments, the carrier protein is CRM ₁₉₇ .

Serotype 22F glycoconjugates of the invention can also be characterized by the ratio (w/w) of saccharide to carrier protein. In some embodiments, the ratio of serotype 22F polysaccharide to carrier protein in the glycoconjugate (w/w) is 0.5 to 3.0 (e.g., about 0.5, about 0.6, about 0.7, about 0.8, approximately 0.9, approximately 1.0, approximately 1.1, approximately 1.2, approximately 1.3, approximately 1.4, approximately 1.5, approximately 1.6, approximately 1.7, approximately 1.8, approximately 1.9, approximately 2.0, approximately 2.1, approximately 2.2, approximately 2.3, approximately 2.4, approximately 2.5, approximately 2.6, approximately 2.7, approximately 2.8, about 2.9, or about 3.0). In other embodiments, the ratio of saccharide to carrier protein (w/w) is 0.5 to 2.0, 0.5 to 1.5, 0.8 to 1.2, 0.5 to 1.0, 1.0 to 1.5, or 1.0 to 2.0. In further embodiments, the ratio of saccharide to carrier protein (w/w) is 0.8 to 1.2. In a preferred embodiment, the ratio of serotype 22F capsular polysaccharide to carrier protein in the conjugate is between 0.9 and 1.1. In some such embodiments, the carrier protein is CRM ₁₉₇ .

Serotype 22F glycoconjugates and the immunogenic composition of the invention may contain a free saccharide that is not covalently conjugated to the carrier protein, but is nonetheless present in the glycoconjugate composition. The free saccharide may be non-covalently associated with (ie, non-covalently associated with, adsorbed to, or enclosed in or with) the glycoconjugate.

In a preferred embodiment, the serotype 22F glycoconjugate contains less than about 50%, 45%, 40%, 35%, 30%, 25%, 20%, or 15% free serotype 22F polysaccharide compared to the total serotype 22F polysaccharide. In a preferred embodiment, the serotype 22F glycoconjugate contains less than about 40% free serotype 22F polysaccharide compared to the total serotype 22F polysaccharide. In a preferred embodiment, the serotype 22F glycoconjugate contains less than about 25% free serotype 22F polysaccharide compared to the total serotype 22F polysaccharide. In a preferred embodiment, the serotype 22F glycoconjugate contains less than about 20% free serotype 22F polysaccharide compared to the total serotype 22F polysaccharide. In a preferred embodiment, the serotype 22F glycoconjugate contains less than about 15% free serotype 22F polysaccharide compared to the total serotype 22F polysaccharide.

Serotype 22F glycoconjugates can also be characterized by their molecular size distribution (K _d ). Gel permeation chromatography media (CL-4B) can be used to determine the relative molecular size distribution of the conjugate. Gel permeation chromatography (SEC) is used in columns fed by gravity to the molecular size distribution profile of the conjugates. Large molecules excluded from pores in media elute more rapidly than small molecules. Fraction collectors are used to collect column eluate. Fractions are examined colorimetrically using saccharide analysis. To determine K _d , the columns are calibrated to establish the fraction in which the molecules are completely excluded (V ₀ ), (K _d =0), and the fraction that represents the maximum retention (V _i ), (K _d =1). The fraction in which the specified characteristic of the sample (V _e ) is achieved is related to K _d by the expression, K _d =(V _e -V ₀ )/(V _i -V ₀ ).

In a preferred embodiment, at least 30% of the serotype 22F glycoconjugate has a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 40% of the glycoconjugate has a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85% of the serotype 22F glycoconjugate has a K _d less than or equal to 0.3 in the column CL-4B. In a preferred embodiment, at least 60% of the serotype 22F glycoconjugate has a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 50% to 80% of the serotype 22F glycoconjugate has a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 65% to 80% of the serotype 22F glycoconjugate has a K _d less than or equal to 0.3 in a CL-4B column.

1.3.3. Glycoconjugates from S. pneumoniae serotype 33F

In one embodiment, serotype 33F glycoconjugates are prepared by activating the polysaccharide with 1-cyano-4-dimethylamino pyridinium tetrafluoroborate (CDAP) to form a cyanate ester. The activated polysaccharide can be attached directly or through a spacer (linker) group to the amino group on the carrier protein. For example, the spacer may be a cystamine or cysteamine yielding a thiolated polysaccharide that may be coupled to the carrier via a thioether bond formed after reaction with a maleimide-activated carrier protein (e.g., using GMBS) or a haloacetylated carrier protein (e.g., using iodoacetamide, SIB, SIAB, sulfo-SIAB, SIA, or SBAP). Preferably, the cyanate ester (optionally prepared using CDAP chemistry) is coupled to hexanediamine or adipic acid hydrazide (ADH) and the amino-derivatized saccharide is conjugated to the carrier protein using carbodiimide (e.g., EDAC or EDC) chemistry through the carboxyl group on the protein. carrier. Such conjugates are described, for example, in WO 93/15760, WO 95/08348 and WO 96/129094.

Other suitable methods use carbodiimides, hydrazides, active esters, norborane, p-nitrobenzoic acid, N-hydroxysuccinimide, S-NHS, EDC, TSTU. Many of these are described in International Patent Publication No. WO 98/42721. The conjugation may include a carbonyl linker which may be formed by the reaction of the free hydroxyl group of the saccharide with CDI (see Bethell et al. (1979) J. Biol. Chern. 254: 2572-2574; Hearn et al. (1981) J. Chromatogr 218: 509-518), followed by reaction with the protein to form a carbamate bond. This may include reducing the anomeric end to a primary hydroxyl group, optionally protecting/deprotecting the primary hydroxyl group, reacting the primary hydroxyl group with a CDI to form a CDI carbamate intermediate, and reacting a CDI carbamate intermediate with an amino group on a protein.

In certain embodiments, serotype 33F glycoconjugates of the invention are prepared using reductive amination. In such an embodiment, the serotype 33F glycoconjugates of the invention can be prepared using aqueous phase reductive amination (RAG/water). Reductive amination in the aqueous phase has been successfully used to prepare a pneumococcal conjugate vaccine (see eg WO 2006/110381). Preferably, although reductive amination is used, serotype 33F glycoconjugates are prepared by reductive amination in DMSO (RAC/DMSO). In view of the problems associated with the retention of O-acetyl functionality when using the RAC/water process, reductive amination in DMSO is preferred. RAC/DMSO has been successfully used to make a pneumococcal conjugate vaccine (see eg WO 2006/110381).

In preferred embodiments, the serotype 33F glycoconjugates of the invention are prepared using eTEC conjugation (hereinafter referred to as "eTEC linked serotype 33F glycoconjugates") such as described in Examples 1, 2 and 3 and in WO 2014/027302. Said 33F glycoconjugates contain a saccharide covalently conjugated to the carrier protein by one or more eTEC spacers, wherein the saccharide is covalently conjugated to the eTEC spacer via a carbamate bond, and wherein the carrier protein is covalently conjugated to the eTEC spacer via an amide bond. The eTEC linked glycoconjugates according to the invention can be represented by the general formula (III):

where the atoms that contain the eTEC spacer are contained in the central block. The eTEC spacer includes seven linear atoms (ie, -C(O)NH(CH ₂ ) ₂ SCH ₂ C(O)-) and provides for stable thioether and amide bonds between the saccharide and the carrier protein.

The synthesis of an eTEC linked glycoconjugate involves reacting an activated hydroxyl group of a saccharide with an amino group of a thioalkylamine reagent, such as cystamine or cysteineamine, or a salt thereof, forming a carbamate bond with the saccharide, providing a thiolated saccharide. The formation of one or more free sulfhydryl groups is carried out by reaction with a reducing agent, providing an activated thiolated saccharide. Reaction of the free sulfhydryl groups of an activated thiolated saccharide with an activated carrier protein having one or more α-haloacetamide groups on an amine containing residues forms a thioether bond to form a conjugate wherein the carrier protein is attached to the eTEC spacer via an amide bond.

In the serotype 33F glycoconjugates of the invention, the saccharide may be a polysaccharide or an oligosaccharide. The carrier protein may be selected from any suitable carrier, as described herein, or known to those skilled in the art. In numerous embodiments, the saccharide is a polysaccharide. In some such embodiments, the carrier protein is CRM ₁₉₇ . In some such embodiments, the eTEC linked glycoconjugate comprises an S. pneumoniae serotype 33F capsular polysaccharide.

In particularly preferred embodiments, the eTEC linked glycoconjugate comprises a Pn-33F capsular polysaccharide that is covalently conjugated to CRM ₁₉₇ via an eTEC spacer (eTEC linked serotype 33F glycoconjugates).

In some embodiments, the serotype 33F glycoconjugates of the present invention comprise a saccharide having a molecular weight of 10 kDa to 2000 kDa. In other such embodiments, the saccharide has a molecular weight of 50 kDa to 2000 kDa. In further such embodiments, the saccharide has a molecular weight of 50 kDa to 1750 kDa; from 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 1750 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1750 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

In some embodiments, the serotype 33F glycoconjugate of the invention has a molecular weight of 50 kDa to 20,000 kDa. In other embodiments, the serotype 33F glycoconjugate has a molecular weight of 500 kDa to 10,000 kDa. In other embodiments, the serotype 33F glycoconjugate has a molecular weight of 200 kDa to 10,000 kDa. In yet other embodiments, the serotype 33F glycoconjugate has a molecular weight of 1000 kDa to 3000 kDa.

In further embodiments, the serotype 33F glycoconjugate of the invention has a molecular weight of 200 kDa to 20,000 kDa; from 200 kDa to 15000 kDa; from 200 kDa to 10,000 kDa; from 200 kDa to 7500 kDa; from 200 kDa to 5000 kDa; from 200 kDa to 3000 kDa; from 200 kDa to 1000 kDa; from 500 kDa to 20,000 kDa; from 500 kDa to 15000 kDa; from 500 kDa to 12500 kDa; from 500 kDa to 10,000 kDa; from 500 kDa to 7500 kDa; from 500 kDa to 6000 kDa; from 500 kDa to 5000 kDa; from 500 kDa to 4000 kDa; from 500 kDa to 3000 kDa; from 500 kDa to 2000 kDa; from 500 kDa to 1500 kDa; from 500 kDa to 1000 kDa; from 750 kDa to 20,000 kDa; from 750 kDa to 15000 kDa; from 750 kDa to 12500 kDa; from 750 kDa to 10,000 kDa; from 750 kDa to 7500 kDa; from 750 kDa to 6000 kDa; from 750 kDa to 5000 kDa; from 750 kDa to 4000 kDa; from 750 kDa to 3000 kDa; from 750 kDa to 2000 kDa; from 750 kDa to 1500 kDa; from 1000 kDa to 15000 kDa; from 1000 kDa to 12500 kDa; from 1000 kDa to 10000 kDa; from 1000 kDa to 7500 kDa; from 1000 kDa to 6000 kDa; from 1000 kDa to 5000 kDa; from 1000 kDa to 4000 kDa; from 1000 kDa to 2500 kDa; from 2000 kDa to 15000 kDa; from 2000 kDa to 12500 kDa; from 2000 kDa to 10000 kDa; from 2000 kDa to 7500 kDa; from 2000 kDa to 6000 kDa; from 2000 kDa to 5000 kDa; from 2000 kDa to 4000 kDa; from 2000 kDa to 3000 kDa; from 3000 kDa to 20000 kDa; from 3000 kDa to 15000 kDa; from 3000 kDa to 12500 kDa; from 3000 kDa to 10000 kDa; from 3000 kDa to 9000 kDa; from 3000 kDa to 8000 kDa; from 3000 kDa to 7000 kDa; from 3000 kDa to 6000 kDa; 3000 kDa to 5000 kDa or 3000 kDa to 4000 kDa. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

Another way to characterize the serotype 33F glycoconjugates of the invention is the number of lysine residues in the carrier protein (eg CRM ₁₉₇ ) that become conjugated to the saccharide, which can be characterized as the range of conjugated lysines (degree of conjugation).

In a preferred embodiment, the degree of conjugation of the serotype 33F glycoconjugate of the invention is 2 to 20, 4 to 16, 2 to 15, 2 to 13, 2 to 10, 2 to 8, 2 to 6, 2 to 5, 2 to 4, 3 to 15, 3 to 13, 3 to 10, 3 to 8, 3 to 6, 3 to 5, 3 to 4, 5 to 15, 5 up to 10, 8 to 15, 8 to 12, 10 to 15, or 10 to 12. In one embodiment, the degree of conjugation of the serotype 33F glycoconjugate of the invention is about 2, about 3, about 4, about 5, about 6 , about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, about 16, about 17, about 18, about 19, or about 20. In a preferred embodiment, the degree of conjugation glycoconjugate serotype 33F according to the invention is from 4 to 16. In some still x embodiments, the carrier protein is CRM ₁₉₇ .

In a preferred embodiment, the carrier protein contains CRM ₁₉₇ which contains 39 lysine residues. In some such embodiments, CRM ₁₉₇ may contain from 4 to 16 of the 39 lysine residues covalently linked to the saccharide. Another way to express this parameter is that from about 10% to about 41% of CRM-197 lysins are covalently linked to the saccharide. In another such embodiment, CRM ₁₉₇ may contain from 2 to 20 of the 39 lysine residues covalently linked to the saccharide. Another way to express this parameter is that from about 5% to about 50% of the CRM ₁₉₇ lysins are covalently linked to the saccharide. In some embodiments, CRM ₁₉₇ may contain about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, or about 16 lysine residues. of 39 covalently linked to the saccharide.

In numerous embodiments, the carrier protein is covalently conjugated to the eTEC spacer via an amide bond to one or more ε-amino groups of lysine residues on the carrier protein. In some such embodiments, the carrier protein contains 2 to 20 lysine residues covalently conjugated to a saccharide. In other such embodiments, the carrier protein contains 4 to 16 lysine residues covalently conjugated to a saccharide.

Serotype 33F glycoconjugates of the invention can also be characterized by the ratio (w/w) of saccharide to carrier protein. In some embodiments, the ratio of saccharide to carrier protein (w/w) is 0.2 to 4.0 (e.g., about 0.2, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, about 1.8, about 1.9, about 2.0, about 2.1, about 2.2, about 2.3, about 2.4, about 2.5, about 2.6, about 2.7, about 2.8, about 2.9, about 3.0, about 3.1, about 3.2, about 3.3, about 3.4, about 3.5, about 3.6, about 3.7, about 3.8, about 3.9, or about 4.0). In other embodiments, the ratio of saccharide to carrier protein (w/w) is 1.0 to 2.5. In further embodiments, the ratio of saccharide to carrier protein (w/w) is 0.4 to 1.7. In some such embodiments, the carrier protein is CRM ₁₉₇ .

The frequency of saccharide chain attachments to lysine on the carrier protein is another parameter for characterizing the serotype 33F glycoconjugates of the invention. For example, in some embodiments, at least one covalent bond between the carrier protein and the polysaccharide occurs for every 4 saccharide repeat units of the polysaccharide. In another embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 10 saccharide repeating units of the polysaccharide. In another embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 15 saccharide repeating units of the polysaccharide. In a further embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 25 saccharide repeat units of the polysaccharide.

In numerous embodiments, the carrier protein is CRM ₁₉₇ and covalent bonding via the eTEC spacer between CRM ₁₉₇ and the polysaccharide occurs at least once for every 4, 10, 15, or 25 saccharide repeat units of the polysaccharide.

In other embodiments, the conjugate contains at least one covalent bond between the carrier protein and the saccharide for every 5 to 10 saccharide repeat units; for every 2 to 7 saccharide repeat units; for every 3 to 8 saccharide repeat units; for every 4 to 9 saccharide repeat units; for every 6 to 11 saccharide repeat units; for every 7 to 12 saccharide repeat units; for every 8 to 13 saccharide repeat units; for every 9 to 14 saccharide repeat units; for every 10 to 15 saccharide repeat units; for every 2 to 6 saccharide repeat units, for every 3 to 7 saccharide repeat units; for every 4 to 8 saccharide repeat units; for every 6 to 10 saccharide repeat units; for every 7 to 11 saccharide repeat units; for every 8 to 12 saccharide repeat units; for every 9 to 13 saccharide repeat units; for every 10 to 14 saccharide repeat units; for every 10 to 20 saccharide repeat units; for every 4 to 25 saccharide repeat units, or for every 2 to 25 saccharide repeat units. In numerous embodiments, the carrier protein is CRM ₁₉₇ .

In another embodiment, at least one bond between the carrier protein and the saccharide occurs every 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 saccharide polysaccharide repeat units. In one embodiment, the carrier protein is CRM ₁₉₇ . Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

An important factor in the conjugation process is the development of conditions that allow the retention of potentially low-stability non-saccharide substituent functional groups of individual components, such as O-acyl, phosphate or glycerol phosphate side chains, which can form part of the saccharide epitopes.

In one embodiment, the serotype 33F glycoconjugates of the invention comprise a saccharide that has a degree of O-acetylation between 10% and 100%. In some such embodiments, the saccharide has a degree of O-acetylation from 50% to 100%. In other such embodiments, the saccharide has a degree of O-acetylation from 75% to 100%. In further embodiments, the saccharide has a degree of O-acetylation greater than or equal to 70% (≥70%).

In a preferred embodiment, the serotype 33F glycoconjugate of the invention contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 mM acetate per mM capsular polysaccharide serotype 33F. In a preferred embodiment, the glycoconjugate contains at least 0.5, 0.6, or 0.7 mM acetate per mM serotype 33F capsular polysaccharide. In a preferred embodiment, the glycoconjugate contains at least 0.6 mM acetate per mM serotype 33F capsular polysaccharide. In a preferred embodiment, the glycoconjugate contains at least 0.7 mM acetate per mM serotype 33F capsular polysaccharide. In a preferred embodiment, the presence of O-acetyl groups is determined using ion-HPLC analysis.

In a preferred embodiment, the ratio of mM acetate per mM serotype 33F polysaccharide in the glycoconjugate to mM acetate per mM serotype 33F polysaccharide in the isolated polysaccharide is at least 0.6, 0.65, 0.7, 0.75, 0, 8, 0.85, 0.9, or 0.95. In a preferred embodiment, the ratio of mM acetate per mM serotype 33F polysaccharide in the glycoconjugate to mM acetate per mM serotype 33F polysaccharide in the isolated polysaccharide is at least 0.7. In a preferred embodiment, the ratio of mM acetate per mM serotype 33F polysaccharide in the glycoconjugate to mM acetate per mM serotype 33F polysaccharide in the isolated polysaccharide is at least 0.9.

In a preferred embodiment, the ratio of mM acetate per mM serotype 33F polysaccharide in the glycoconjugate to mM acetate per mM serotype 33F polysaccharide in the activated polysaccharide is at least 0.6, 0.65, 0.7, 0.75, 0, 8, 0.85, 0.9, or 0.95. In a preferred embodiment, the ratio of mM acetate per mM serotype 33F polysaccharide in the glycoconjugate to mM acetate per mM serotype 33F polysaccharide in the activated polysaccharide is at least 0.7. In a preferred embodiment, the ratio of mM acetate per mM serotype 33F polysaccharide in the glycoconjugate to mM acetate per mM serotype 33F polysaccharide in the activated polysaccharide is at least 0.9. The serotype 33F glycoconjugates and the immunogenic composition of the invention may contain a free saccharide that is not covalently conjugated to the carrier protein but is nonetheless present in the glycoconjugate composition. The free saccharide may be non-covalently associated with (ie, non-covalently associated with, adsorbed to, or enclosed in or with) the glycoconjugate.

In some embodiments, the serotype 33F glycoconjugates of the invention contain less than about 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% free serotype 33F polysaccharide compared to with total polysaccharide serotype 33F. Preferably, the serotype 33F glycoconjugate contains less than 15% Free saccharide, more preferably less than 10% Free saccharide, and even more preferably less than 5% Free saccharide. In a preferred embodiment, the serotype 33F glycoconjugate contains less than about 25% free serotype 33F polysaccharide compared to the total serotype 33F polysaccharide. In a preferred embodiment, the serotype 33F glycoconjugate contains less than about 20% free serotype 33F polysaccharide compared to the total serotype 33F polysaccharide. In a preferred embodiment, the serotype 33F glycoconjugate contains less than about 15% free serotype 33F polysaccharide compared to the total serotype 33F polysaccharide.

In some preferred embodiments, the invention provides a serotype 33F glycoconjugate having one or more of the following features alone or in combination: the polysaccharide has a molecular weight of 50 kDa to 2000 kDa; the glycoconjugate has a molecular weight of 500 kDa to 10,000 kDa; the carrier protein contains 2 to 20 lysine residues covalently linked to the saccharide; the ratio of saccharide to carrier protein (w/w) is from 0.2 to 4.0; the glycoconjugate contains at least a covalent bond between the carrier protein and the polysaccharide for every 4, 10, 15, or 25 saccharide repeat units of the polysaccharide; the saccharide has a degree of O-acetylation from 75% to 100%; the conjugate contains less than about 15% free polysaccharide relative to total polysaccharide; the carrier protein is CRM ₁₉₇ .

Serotype 33F glycoconjugates can also be characterized by their molecular size distribution (K _d ). Gel Permeation Media Chromatography (CL-4B) can be used to determine the relative molecular size distribution of the conjugate as described above.

In one embodiment, at least 15% of the serotype 33F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In one embodiment, at least 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, or 90% of the serotype 33F glycoconjugates of the invention have K _d less than or equal to 0.3 in column CL-4B.

In a preferred embodiment, at least 35% of the serotype 33F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In preferred embodiments, at least 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85% of the serotype 33F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 60% of the serotype 33F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 70% of the serotype 33F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column.

In a preferred embodiment, 40% to 90% of serotype 33F glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 50% to 90% of serotype 33F glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 65% to 80% of serotype 33F glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column.

1.3.4. Glycoconjugates from S. pneumoniae serotype 15B

In one embodiment, serotype 15B glycoconjugates are prepared by activating the polysaccharide with 1-cyano-4-dimethylamino pyridinium tetrafluoroborate (CDAP) to form a cyanate ester. The activated polysaccharide can be attached directly or through a spacer (linker) group to the amino group on the carrier protein. For example, the spacer can be a cystamine or cysteamine, yielding a thiolated polysaccharide that can be attached to the carrier via a thioether bond formed after reaction with a maleimide-activated carrier protein (e.g., using GMBS) or a haloacetylated carrier protein (e.g., using iodoacetamide, SIB, SIAB, sulfo-SIAB, SIA, or SBAP). Preferably, the cyanate ester (optionally prepared using CDAP chemistry) is coupled to hexanediamine or adipic acid hydrazide (ADH) and the amino-derivatized saccharide is conjugated to the carrier protein using carbodiimide (e.g., EDAC or EDC) chemistry through the carboxyl group on the protein. carrier. Such conjugates are described, for example, in WO 93/15760, WO 95/08348 and WO 96/129094.

Other suitable methods use carbodiimides, hydrazides, active esters, norborane, p-nitrobenzoic acid, N-hydroxysuccinimide, S-NHS, EDC, TSTU. Many of them are described in International Patent Publication No. WO 98/42721. The conjugation may include a carbonyl linker which may be formed by the reaction of the free hydroxyl group of the saccharide with CDI (see Bethell et al. (1979) J. Biol. Chern. 254: 2572-2574; Hearn et al. (1981) J. Chromatogr , 218: 509-518), followed by reaction with the protein to form a carbamate bond. This may include reducing the anomeric end to a primary hydroxyl group, optionally protecting/deprotecting the primary hydroxyl group, reacting the primary hydroxyl group with a CDI to form a CDI carbamate intermediate, and reacting a CDI carbamate intermediate with an amino group on a protein.

In preferred embodiments, the serotype 15B glycoconjugates of the invention are prepared using reductive amination. Reductive amination involves two steps, (1) oxidation of the polysaccharide to form aldehyde functional groups from vicinal diols in the individual hexasaccharide unit, (2) reduction of the activated polysaccharide and carrier protein to form a conjugate.

Preferably, the serotype 15B polysaccharide is sized within the target molecular weight (MW) range prior to oxidation. Advantageously, the size of the purified serotype 15B polysaccharide is reduced while retaining critical structural features of the polysaccharide, such as, for example, the presence of O-acetyl groups. Preferably, the size of the purified serotype 15B polysaccharide is reduced using mechanical homogenization (see section 1, 2, 6 above).

The oxidation step may include reaction with periodate. For the purposes of the present invention, the term "periodate" includes both periodate and periodic acid; the term also includes both metaperiodate (IO ₄ ^- ) and orthoperiodate (IO ₆ ^5- ) and various periodate salts (eg, sodium periodate and potassium periodate). In a preferred embodiment, the periodate used to oxidize the serotype 15B capsular polysaccharide is metaperiodate. In a preferred embodiment, the periodate used to oxidize the serotype 15B capsular polysaccharide is sodium metaperiodate.

In a preferred embodiment, the polysaccharide is reacted with 0.01 to 10.0, 0.05 to 5.0, 0.1 to 1.0, 0.5 to 1.0, 0.7 to 0.8, 0.05 to 0.5, 0.1 to 0.3 molar equivalents of oxidizing agent. In a preferred embodiment, the polysaccharide is reacted with about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95 molar equivalents of oxidizing agent. In a preferred embodiment, the polysaccharide is reacted with about 0.15 molar equivalents of an oxidizing agent. In a preferred embodiment, the polysaccharide is reacted with about 0.25 molar equivalents of an oxidizing agent. In a preferred embodiment, the polysaccharide is reacted with about 0.5 molar equivalents of an oxidizing agent. In a preferred embodiment, the polysaccharide is reacted with about 0.6 molar equivalents of an oxidizing agent. In a preferred embodiment, the polysaccharide is reacted with about 0.7 molar equivalents of an oxidizing agent.

In a preferred embodiment, the reaction time is 1 hour to 50 hours, 10 hours to 30 hours, 15 hours to 20 hours, 15 hours to 17 hours, or about 16 hours.

In a preferred embodiment, the reaction temperature is maintained in the range of 15°C to 45°C, 15°C to 30°C, 20°C to 25°C. In a preferred embodiment, the reaction temperature is maintained at approximately 23°C.

In a preferred embodiment, the oxidation reaction is carried out in a buffer selected from sodium phosphate, potassium phosphate, 2-(N-morpholino)ethanesulfonic acid (MES), or Bis-Tris. In a preferred embodiment, the buffer is potassium phosphate.

In a preferred embodiment, the buffer has a concentration of 1 mM to 500 mM, 1 mM to 300 mM, or 50 mM to 200 mM. In a preferred embodiment, the buffer has a concentration of approximately 100 mm.

In a preferred embodiment, the oxidation reaction is carried out at a pH of 4.0 to 8.0, 5.0 to 7.0, or 5.5 to 6.5. In a preferred embodiment, the pH is about 6.0.

In a preferred embodiment, activated serotype 15B capsular polysaccharide is prepared by reacting 0.5 mg/mL to 5 mg/mL of isolated serotype 15B capsular polysaccharide with 0.2 to 0.3 molar equivalents of periodate at 20°C to 25°C. °C.

In a preferred embodiment, the serotype 15B activated capsular polysaccharide is purified. The serotype 15B activated capsular polysaccharide is purified according to methods known to those skilled in the art such as gel permeation chromatography (GPC), dialysis, or ultrafiltration/diafiltration. For example, the activated capsular polysaccharide is purified by concentration and diafiltration using an ultrafiltration device.

In a preferred embodiment, the oxidation state of the activated serotype 15B capsular polysaccharide is 2 to 20, 2 to 15, 2 to 10, 2 to 5, 5 to 20, 5 to 15, 5 to 10, 10 up to 20, 10 to 15, or 15 to 20. In a preferred embodiment, the oxidation state of the activated serotype 15B capsular polysaccharide is 2 to 10, 4 to 8, 4 to 6, 6 to 8, 6 to 12 , 8 to 12, 9 to 11, 10 to 16, 12 to 16, 14 to 18, 16 to 20, 16 to 18, or 18 to 20.

In a preferred embodiment, the serotype 15B activated capsular polysaccharide has a molecular weight of 5 kDa to 500 kDa, 50 kDa to 500 kDa, 50 kDa to 450 kDa, 100 kDa to 400 kDa, 100 kDa to 350 kDa. In a preferred embodiment, the serotype 15B activated capsular polysaccharide has a molecular weight of 100 kDa to 350 kDa. In a preferred embodiment, the serotype 15B activated capsular polysaccharide has a molecular weight of 100 kDa to 300 kDa. In a preferred embodiment, the serotype 15B activated capsular polysaccharide has a molecular weight of 100 kDa to 250 kDa.

In a preferred embodiment, the serotype 15B activated capsular polysaccharide contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 mM acetate per mm of the specified capsular polysaccharide serotype 15B. In a preferred embodiment, the activated serotype 15B capsular polysaccharide contains at least 0.5, 0.6, or 0.7 mM acetate per mM of said serotype 15B capsular polysaccharide. In a preferred embodiment, the activated serotype 15B capsular polysaccharide contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide. In a preferred embodiment, the activated serotype 15B capsular polysaccharide contains at least 0.7 mM acetate per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the serotype 15B activated capsular polysaccharide contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 mM glycerol per mM of the indicated serotype 15B capsular polysaccharide. In a preferred embodiment, the activated serotype 15B capsular polysaccharide contains at least 0.5, 0.6, or 0.7 mM glycerol per mM of said serotype 15B capsular polysaccharide. In a preferred embodiment, the activated serotype 15B capsular polysaccharide contains at least 0.6 mM glycerol per mM of said serotype 15B capsular polysaccharide. In a preferred embodiment, the activated serotype 15B capsular polysaccharide contains at least 0.7 mM glycerol per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the activated serotype 15B capsular polysaccharide has a molecular weight of 100 kDa to 250 kDa and contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the activated serotype 15B capsular polysaccharide has a molecular weight of 100 kDa to 250 kDa and contains at least 0.6 mM glycerol per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the activated serotype 15B capsular polysaccharide contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide and at least 0.6 mM glycerol per mM of said serotype 15B capsular polysaccharide.

In a preferred embodiment, the activated serotype 15B capsular polysaccharide has a molecular weight of 100 kDa to 250 kDa and contains at least 0.6 mM acetate per mM of said serotype 15B capsular polysaccharide and at least 0.6 mM glycerol per mM of the indicated serotype 15B capsular polysaccharide.

In one embodiment, the activated serotype 15B capsular polysaccharide is lyophilized, optionally in the presence of a saccharide. In a preferred embodiment, the saccharide is selected from sucrose, trehalose, raffinose, stachyose, melecytose, dextran, mannitol, lactitol and palatinite. In a preferred embodiment, the saccharide is sucrose. The lyophilized activated capsular polysaccharide can then be mixed with a solution containing a carrier protein.

In another embodiment, the activated serotype 15B capsular polysaccharide is mixed with a carrier protein and optionally lyophilized in the presence of the saccharide. In a preferred embodiment, the saccharide is selected from sucrose, trehalose, raffinose; stachyosis, melecytosis, dextran, mannitol, lactitol and palatinitis. In a preferred embodiment, the saccharide is sucrose. The co-lyophilized polysaccharide and carrier protein can then be resuspended in solution and reacted with a reducing agent.

The serotype 15B activated capsular polysaccharide may be conjugated to a carrier protein according to a method comprising the step of:

(a) mixing an activated serotype 15B capsular polysaccharide with a carrier protein, and

(b) reacting the compounded activated serotype 15B capsular polysaccharide and carrier protein with a reducing agent to form a serotype 15B protein capsular polysaccharide-carrier conjugate. Conjugation of an activated serotype 15B capsular polysaccharide to a carrier protein by reductive amination in dimethyl sulfoxide (DMSO) is acceptable to maintain the O-acetyl content of the polysaccharide, compared to, for example, reductive amination in aqueous solution, where the level of O-acetylation of the polysaccharide is greatly reduced. In a preferred embodiment, step (a) and step (b) are carried out in DMSO.

In a preferred embodiment, step (a) comprises dissolving the lyophilized serotype 15B capsular polysaccharide in a solution containing carrier protein and DMSO. In a preferred embodiment, step (a) comprises dissolving co-lyophilized serotype 15B capsular polysaccharide and carrier protein in DMSO.

When steps (a) and (b) are carried out in aqueous solution, steps (a) and (b) are carried out in a buffer, preferably selected from PBS, MES, HEPES, Bis-tris, ADA, PIPES, MOPSO, BES, MOPS, DIPSO , MOBS, HEPPSO, POPSO, TEA, EPPS, Bicine, or NERB, at pH 6.0 to 8.5, 7.0 to 8.0, or 7.0 to 7.5. In a preferred embodiment, the buffer is PBS. In a preferred embodiment, the pH is about 7.3.

In a preferred embodiment, the concentration of activated serotype 15B capsular polysaccharide in step (b) is 0.1 mg/mL to 10 mg/mL, 0.5 mg/mL to 5 mg/mL, or 0.5 mg/mL. ml to 2 mg/ml. In a preferred embodiment, the concentration of activated serotype 15B capsular polysaccharide in step (b) is about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2, 1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0 mg/mL.

In a preferred embodiment, the initial input ratio (w/w) of activated serotype 15B capsular polysaccharide to carrier protein is 5:1 to 0.1:1, 2:1 to 0.1:1, 2:1 to 1 :1, 1.5:1 to 1:1, 0.1:1 to 1:1, 0.3:1 to 1:1, or 0.6:1 to 1:1.

In a preferred embodiment, the initial input ratio of activated serotype 15B capsular polysaccharide to carrier protein is from about 0.6:1 to 1:1. In another preferred embodiment, the initial input ratio of activated serotype 15B capsular polysaccharide to carrier protein is from about 0.6:1 to 1.5:1. This initial input ratio is particularly suitable for obtaining low levels of free polysaccharide in the glycoconjugate.

In a preferred embodiment, the initial input ratio of activated serotype 15B capsular polysaccharide to carrier protein is approximately 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0, 9:1, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1 or 2:1.

In one embodiment, the reducing agent is sodium cyanoborohydride, sodium triacetoxyborohydride, sodium or zinc borohydride in the presence of Bronsted or Lewis acids, aminoboranes such as pyridine-borane, 2-picoline-borane, 2,6-diborane-methanol, dimethylamine- borane, t-BuMeiPrN-BH3, benzylamine-BH ₃ or 5-ethyl-2-methylpyridine borane (PEMB). In a preferred embodiment, the reducing agent is sodium cyanoborohydride. In a preferred embodiment, the reducing agent is sodium 2-picoline-borane.

In a preferred embodiment, the amount of reducing agent used in step (b) is from about 0.1 to 10.0 molar equivalents, from 0.5 to 5.0 molar equivalents, or from 1.0 to 2.0 molar equivalents. equivalents. In a preferred embodiment, the amount of reducing agent used in step (b) is approximately 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2.0 molar equivalents.

In a preferred embodiment, the duration of step (b) is 1 hour to 60 hours, 10 hours to 50 hours, 40 hours to 50 hours, or 42 hours to 46 hours. In a preferred embodiment, the duration of step (b) is approximately 44 hours.

In a preferred embodiment, the reaction temperature in step (b) is maintained at 10°C to 40°C, 15°C to 30°C, or 20°C to 26°C. In a preferred embodiment, the reaction temperature in step (b) is maintained at approximately 23°C.

In a preferred embodiment, the method for preparing a glycoconjugate comprising a S. pneumoniae serotype 15B capsular polysaccharide covalently linked to a carrier protein further comprises the step (step (c)) of blocking unreacted aldehyde (quenched) by adding NaBH ₄ .

In a preferred embodiment, the amount of NaBH ₄ used in step (c) is 0.1 to 10 molar equivalents, 0.5 to 5.0 molar equivalents, or 1.0 to 3.0 molar equivalents. In a preferred embodiment, the amount of NaBH ₄ used in step (c) is approximately 2 molar equivalents.

In a preferred embodiment, the duration of step (c) is 0.1 hour to 10 hours, 0.5 hour to 5 hours, or 2 hours to 4 hours. In a preferred embodiment, the duration of step (c) is approximately 3 hours.

In a preferred embodiment, the reaction temperature in step (c) is maintained at 15°C to 45°C, 15°C to 30°C, or 20°C to 26°C. In a preferred embodiment, the reaction temperature in step (c) is maintained at approximately 23°C.

In a preferred embodiment, the yield from the conjugation step is greater than 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90%. In a preferred embodiment, the yield from the conjugation step (step b) is greater than 60%. In a preferred embodiment, the yield from the conjugation step (step b) is greater than 70%. The yield is the amount of serotype 15B polysaccharide in the conjugate x 100)/the amount of activated polysaccharide used in the conjugation step.

In a preferred embodiment, a method for preparing a glycoconjugate containing a S. pneumoniae serotype 15B capsular polysaccharide covalently linked to a carrier protein comprises the steps of:

(a) sizing the purified serotype 15B polysaccharide by high pressure homogenization;

(b) reacting a serotype 15B size polysaccharide with an oxidizing agent;

(c) mixing the activated serotype 15B polysaccharide with a carrier protein;

(d) reacting the compounded serotype 15B activated polysaccharide and carrier protein with a reducing agent to form a serotype 15B protein-carrier polysaccharide conjugate; and

(e) blocking unreacted aldehyde (quenching) by adding NaBH ₄ .

In a preferred embodiment, the yield in the conjugation step (step d) of the above process is greater than 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85% or 90%. In a preferred embodiment, the yield from the conjugation step (step d) is greater than 60%. In a preferred embodiment, the yield from the conjugation step (step d) is greater than 70%. The yield is the amount of serotype 15B polysaccharide in the conjugate x 100)/the amount of activated polysaccharide used in the conjugation step.

After the serotype 15B capsular polysaccharide has been conjugated to a carrier protein, the polysaccharide-protein conjugate can be purified (enriched relative to the amount of polysaccharide-protein conjugate) using a variety of methods known to the skilled artisan. These methods include dialysis, concentration/diafiltration operations, tangential flow filtration, precipitation/elution, column chromatography (DEAE or hydrophobic interaction chromatography), and depth filtration.

In one embodiment, the carrier protein is as defined in section 1.1. In one embodiment, the carrier protein is selected from the group consisting of: DT (diphtheria toxin), TT (tetanus toxin), CRM ₁₉₇ , other DT mutants, PD (Haemophilus influenzae D protein), or immunologically functional equivalents thereof. In one embodiment, the carrier protein is CRM ₁₉₇ .

In some embodiments, the serotype 15B glycoconjugates of the present invention are conjugated to a carrier protein (eg, CRM ₁₉₇ ) and contain a saccharide having a molecular weight of 5 kDa to 1500 kDa. In other such embodiments, the saccharide has a molecular weight of 10 kDa to 1500 kDa. In further such embodiments, the saccharide has a molecular weight of 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 50 kDa to 250 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 100 kDa to 250 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa; or from 200 kDa to 400 kDa. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention. In some embodiments, the serotype 15B glycoconjugate of the invention has a molecular weight of 50 kDa to 20,000 kDa. In some embodiments, the serotype 15B glycoconjugate of the invention has a molecular weight of 1000 kDa to 20,000 kDa. In a preferred embodiment, the serotype 15B glycoconjugate of the invention has a molecular weight of 3,000 kDa to 20,000 kDa, 5,000 kDa to 10,000 kDa, 5,000 kDa to 20,000 kDa, 8,000 kDa to 20,000 kDa, 8,000 kDa to 16,000 kDa, or 10,000 kDa up to 16000 kDa.

In the following embodiments, the serotype 15B glycoconjugate of the invention has a molecular weight of about 1000 kDa, about 1500 kDa, about 2000 kDa, about 2500 kDa, about 3000 kDa, about 3500 kDa, about 4000 kDa, about 4500 kDa, about 5000 kDa, about 5500 kDa, approximately 6000 kDa, approximately 6500 kDa, approximately 7000 kDa, approximately 7500 kDa, approximately 8000 kDa, approximately 8500 kDa, approximately 9000 kDa, approximately 9500 kDa approximately 10000 kDa, approximately 10500 kDa, approximately 11000 kDa, approximately 11500 kDa , approximately 12000 kDa, approximately 12500 kDa, approximately 13000 kDa, approximately 13500 kDa, approximately 14000 kDa, approximately 14500 kDa, approximately 15000 kDa, approximately 15500 kDa, approximately 16000 kDa, approximately 16500 kDa, approximately 17000 kDa, approximately 17500 kDa, approximately 18000 kD a, approximately 18500 kDa, approximately 19000 kDa, approximately 19500 kDa or approximately 20000 kDa.

In further embodiments, the serotype 15B glycoconjugate of the invention has a molecular weight of 1000 kDa to 20,000 kDa; from 1000 kDa to 15000 kDa; from 1000 kDa to 10000 kDa; from 1000 kDa to 7500 kDa; from 1000 kDa to 5000 kDa; from 1000 kDa to 4000 kDa; from 1000 kDa to 3000 kDa; from 2000 kDa to 20000 kDa; from 2000 kDa to 15000 kDa; from 2000 kDa to 12500 kDa; from 2000 kDa to 10000 kDa; from 2000 kDa to 7500 kDa; from 2000 kDa to 6000 kDa; from 2000 kDa to 5000 kDa; from 2000 kDa to 4000 kDa; or from 2000 kDa to 3000 kDa.

In further embodiments, the serotype 15B glycoconjugate according to the invention has a molecular weight of 3,000 kDa to 20,000 kDa; from 3000 kDa to 15000 kDa; from 3000 kDa to 10000 kDa; from 3000 kDa to 7500 kDa; from 3000 kDa to 5000 kDa; from 3000 kDa to 4000 kDa; from 4000 kDa to 20000 kDa; from 4000 kDa to 15000 kDa; from 4000 kDa to 12500 kDa; from 4000 kDa to 10000 kDa; from 4000 kDa to 7500 kDa; 4000 kDa to 6000 kDa or 4000 kDa to 5000 kDa. In further embodiments, the serotype 15B glycoconjugate according to the invention has a molecular weight of 5,000 kDa to 20,000 kDa; from 5000 kDa to 15000 kDa; from 5000 kDa to 10000 kDa; from 5000 kDa to 7500 kDa; from 6000 kDa to 20000 kDa; from 6000 kDa to 15000 kDa; from 6000 kDa to 12500 kDa; 6000 kDa to 10000 kDa or 6000 kDa to 7500 kDa.

The molecular weight of the glycoconjugate is measured using SEC-MALLS. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention. In one embodiment, said serotype 15B glycoconjugate is prepared using reductive amination.

The serotype 15B glycoconjugates of the invention can also be characterized by the ratio (w/w) of saccharide to carrier protein. In a preferred embodiment, the ratio (weight by weight) of serotype 15B capsular polysaccharide to carrier protein in the conjugate is 0.5 to 3.0 (e.g., about 0.5, about 0.6, about 0.7, about 0 .8, approximately 0.9, approximately 1.0, approximately 1.1, approximately 1.2, approximately 1.3, approximately 1.4, approximately 1.5, approximately 1.6, approximately 1.7, approximately 1 .8, approximately 1.9, approximately 2.0, approximately 2.1, approximately 2.2, approximately 2.3, approximately 2.4, approximately 2.5, approximately 2.6, approximately 2.7, approximately 2 .8, about 2.9, or about 3.0). In a preferred embodiment, the ratio of serotype 15B capsular polysaccharide to carrier protein in the conjugate is 0.4 to 2. In a preferred embodiment, the ratio of serotype 15B capsular polysaccharide to carrier protein in the conjugate is 0.5 to 2.0, 0.5 to 1.5, 0.5 to 1.0, 1.0 to 1.5, 1.0 to 2.0. In a preferred embodiment, the ratio of serotype 15B capsular polysaccharide to carrier protein in the conjugate is between 0.7 and 0.9.

Serotype 15B glycoconjugates and the immunogenic composition of the invention may contain a free saccharide that is not covalently conjugated to the carrier protein, but is nevertheless present in the glycoconjugate composition. The free saccharide may be non-covalently associated with (ie, non-covalently associated with, adsorbed to, or enclosed in or with) the glycoconjugate.

In a preferred embodiment, the serotype 15B glycoconjugate of the invention contains less than about 50%, 45%, 40%, 35%, 30%, 25%, 20%, or 15% free serotype 15B capsular polysaccharide compared to the total capsular polysaccharide serotype 15B. In a preferred embodiment, the serotype 15B glycoconjugate of the invention contains less than about 25% free serotype 15B capsular polysaccharide compared to the total serotype 15B capsular polysaccharide. In a preferred embodiment, the serotype 15B glycoconjugate of the invention contains less than about 20% free serotype 15B capsular polysaccharide compared to the total serotype 15B capsular polysaccharide. In a preferred embodiment, the serotype 15B glycoconjugates of the invention contain less than about 15% free serotype 15B capsular polysaccharide compared to the total serotype 15B capsular polysaccharide.

Serotype 15B glycoconjugates can also be characterized by their molecular size distribution (K _d ). Gel Permeation Media Chromatography (CL-4B) can be used to determine the relative molecular size distribution of the conjugate as described above.

In a preferred embodiment, at least 20% of the serotype 15B glycoconjugates of the invention have a Kd less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 30% of the immunogenic conjugate has a Kd less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 40% of the serotype 15B glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85% of the serotype 15 glycoconjugates of the invention have a K _d less than or equal to 0.3 in column CL-4B. In a preferred embodiment, at least 60% of the serotype 15B glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 70% of the serotype 15B glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column.

In a preferred embodiment, 40% to 90% of serotype 15B glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 50% to 90% of serotype 15B glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 65% to 80% of serotype 15B glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column.

In a preferred embodiment, the serotype 15B glycoconjugate of the invention contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 mM acetate per mM capsular polysaccharide serotype 15B. In a preferred embodiment, the glycoconjugate contains at least 0.5, 0.6, or 0.7 mM acetate per mM serotype 15B capsular polysaccharide. In a preferred embodiment, the glycoconjugate contains at least 0.6 mM acetate per mM serotype 15B capsular polysaccharide. In a preferred embodiment, the glycoconjugate contains at least 0.7 mM acetate per mM serotype 15B capsular polysaccharide. In a preferred embodiment, the presence of O-acetyl groups is determined using ion-HPLC analysis.

In a preferred embodiment, the ratio of mM acetate per mM serotype 15B capsular polysaccharide in the serotype 15B glycoconjugate to mM acetate per mM serotype 15B capsular polysaccharide in the isolated polysaccharide is at least 0.6, 0.65, 0.7, 0, 75, 0.8, 0.85, 0.9, or 0.95. In a preferred embodiment, the ratio of mM acetate per mM serotype 15B capsular polysaccharide in the serotype 15B glycoconjugate to mM acetate per mM serotype 15B capsular polysaccharide in the isolated polysaccharide is at least 0.7. In a preferred embodiment, the ratio of mM acetate per mM serotype 15B capsular polysaccharide in the serotype 15B glycoconjugate to mM acetate per mM serotype 15B capsular polysaccharide in the isolated polysaccharide is at least 0.9. In a preferred embodiment, the presence of O-acetyl groups is determined using ion-HPLC analysis.

In a preferred embodiment, the ratio of mM acetate per mM serotype 15B capsular polysaccharide in the serotype 15B glycoconjugate to mM acetate per mM serotype 15B capsular polysaccharide in the activated polysaccharide is at least 0.6, 0.65, 0.7, 0, 75, 0.8, 0.85, 0.9, or 0.95. In a preferred embodiment, the ratio of mM acetate per mM serotype 15B capsular polysaccharide in the serotype 15B glycoconjugate to mM acetate per mM serotype 15B capsular polysaccharide in the activated polysaccharide is at least 0.7. In a preferred embodiment, the ratio of mM acetate per mM serotype 15B capsular polysaccharide in the serotype 15B glycoconjugate to mM acetate per mM serotype 15B capsular polysaccharide in the activated polysaccharide is at least 0.9. In a preferred embodiment, the presence of O-acetyl groups is determined using ion-HPLC analysis.

In a preferred embodiment, the serotype 15B glycoconjugate of the invention contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 mM glycerol per mM capsular polysaccharide serotype 15B. In a preferred embodiment, the serotype 15B glycoconjugate of the invention contains at least 0.5, 0.6, or 0.7 mM glycerol per mM serotype 15B capsular polysaccharide. In a preferred embodiment, the serotype 15B glycoconjugate of the invention contains at least 0.6 mM glycerol per mM serotype 15B capsular polysaccharide. In a preferred embodiment, the serotype 15B glycoconjugate of the invention contains at least 0.7 mM glycerol per mM serotype 15B capsular polysaccharide.

Another way to characterize the serotype 15B glycoconjugates of the invention is the number of lysine residues in the carrier protein (eg CRM ₁₉₇ ) that become conjugated to the saccharide, which can be characterized as the range of conjugated lysines (degree of conjugation). Evidence of a lysine modification of the carrier protein, due to covalent bonds with polysaccharides, can be obtained by amino acid analysis using standard methods known to those skilled in the art. Conjugation results in a reduction in the amount of lysine residues recovered compared to the original CRM ₁₉₇ protein material used to form the conjugate materials.

In a preferred embodiment, the degree of conjugation of the serotype 15B glycoconjugate according to the invention is 2 to 15, 2 to 13, 2 to 10, 2 to 8, 2 to 6, 2 to 5, 2 to 4, 3 to 15, 3 to 13, 3 to 10, 3 to 8, 3 to 6, 3 to 5, 3 to 4, 5 to 15, 5 to 10, 8 to 15, 8 up to 12, 10 to 15, or 10 to 12. In one embodiment, the degree of conjugation of the serotype 15B glycoconjugate of the invention is about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, or about 15. In a preferred embodiment, the degree of conjugation of the serotype 15B glycoconjugate of the invention is from 2 to 5.

1.3.5. Glycoconjugates from S. pneumoniae serotype 12F

In the S. pneumoniae serotype 12F glycoconjugates of the present invention, the saccharide is selected from the group consisting of a polysaccharide and an oligosaccharide, and the carrier protein is selected from any suitable carrier as described herein or known to one of skill in the art. In some preferred embodiments, the saccharide is a serotype 12F polysaccharide from S. pneumoniae.

In one embodiment, glycoconjugates from S. pneumoniae serotype 12F are prepared using CDAP. The polysaccharides are activated with 1-cyano-4-dimethylamino pyridinium tetrafluoroborate (CDAP) to form the cyanate ester. The activated polysaccharide is then attached directly or via a spacer (linker) group to the amino group on the carrier protein (preferably CRM ₁₉₇ ). For example, the spacer may be a cystamine or cysteamine yielding a thiolated polysaccharide that can be attached to the carrier via a thioether bond formed after reaction with a maleimide-activated carrier protein (e.g. using GMBS) or a haloacetylated carrier protein (e.g. using iodoacetamide, SIB, SIAB, sulfo-SIAB, SIA, or SBAP). Preferably, the cyanate ester (optionally prepared using CDAP chemistry) is coupled to hexanediamine or adipic acid hydrazide (ADH) and the amino-derivatized saccharide is conjugated to a carrier protein (e.g. CRM ₁₉₇ ) using a carbodiimide (e.g. EDAC or EDC) chemistry through a carboxyl group on a protein carrier.

Other conjugation methods use carbodiimides, hydrazides, active esters, norborane, p-nitrobenzoic acid, N-hydroxysuccinimide, S-NHS, EDC, TSTU. Many of these are described in International Patent Publication No. WO 98/42721. The conjugation may include a carbonyl linker which may be formed by the reaction of the free hydroxyl group of the saccharide with CDI (see Bethell et al. (1979) J. Biol. Chern. 254: 2572-2574; Hearn et al. (1981) J. Chromatogr , 218: 509-518), followed by reaction with the protein to form a carbamate bond. This may include reducing the anomeric end to a primary hydroxyl group, optionally protecting/deprotecting the primary hydroxyl group, reacting the primary hydroxyl group with a CDI to form a CDI carbamate intermediate, and reacting a CDI carbamate intermediate with an amino group on a protein.

In one embodiment, capsular polysaccharides from S. pneumoniae 12F serotypes are conjugated to a carrier protein via reductive amination. Reductive amination involves two steps, (1) oxidation of the polysaccharide to form aldehyde functional groups from vicinal diols in the individual hexasaccharide unit, (2) reduction of the activated polysaccharide and carrier protein to form a conjugate.

Prior to oxidation, the serotype 12F polysaccharide is optionally hydrolyzed (sorted by size). Mechanical or chemical hydrolysis may be used. Chemical hydrolysis can be carried out using acetic acid.

In one embodiment, the oxidizing agent is a periodate. The term "periodate" includes both periodate and periodic acid (see below).

In a preferred embodiment, the oxidizing agent is a 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) free radical and N-chlorosuccinimide (NCS) as a co-oxidizing agent. In such an embodiment, glycoconjugates from S. pneumoniae serotype 12F are prepared using the 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) free radical in order to oxidize primary saccharide alcohols to aldehydes using N-chlorosuccinimide (NCS ) as a co-oxidant (hereinafter referred to as "TEMPO/NCS oxidation"), such as described in Example 7 and in WO 2014/097099. Therefore, in one aspect, glycoconjugates from S. pneumoniae serotype 12F can be obtained by a method comprising the steps of: a) reacting the 12F saccharide with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and N-chlorosuccinimide (NCS) in an aqueous solvent, to obtain an activated saccharide; and b) reacting the activated saccharide with a carrier protein containing one or more amino groups (hereinafter referred to as "TEMPO/NCS reductive amination"). In one aspect, glycoconjugates from S. pneumoniae serotype 12F are prepared according to said method. In one embodiment, the oxidation state of the activated 12F saccharide is in the range of 1 to 50, 1 to 40, 1 to 30, 1 to 20, 1 to 10, 1 to 5, 3 to 40, 3 to 30, 3 to 20, 3 to 10, 4 to 40, 4 to 30, 4 to 20, 4 to 10, 5 to 30, 5 to 25, 5 to 20, 5 to 10, 6 to 50, 6 to 40, 6 to 30, 6 to 20, 6 to 15, 6 to 14, 6 to 13, 6 to 12, 6 to 11, 6 to 10, 7 to 40, 7 to 30, 7 to 20, 7 to 15, 7 to 14, 7 to 13, 7 to 12, 7 to 11, 7 to 10, 8 up to 40, 8 to 30, 8 to 20, 8 to 15, 8 to 14, 8 to 13, 8 to 13, 8 to 12, 8 to 11, 8 to 10, 9 up to 40, 9 to 30, 9 to 20, 9 to 15, 10 to 40, 10 to 30, 10 to 20, or 10 to 15. In a further aspect, the oxidation state of the activated saccharide is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12.13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40. Pre preferably, the carrier protein is CRM ₁₉₇ .

In one embodiment, prior to step a), the 12F saccharide is hydrolyzed to a molecular weight ranging from 100 kDa to 400 kDa. For example, in one aspect, the molecular weight ranges are 100 kDa to 350 kDa, 100 kDa to 300 kDa, 100 kDa to 250 kDa, 100 kDa to 200 kDa, 100 kDa to 150 kDa, 200 kDa to 400 kDa, 200 kDa to 350 kDa, 200 kDa to 300 kDa, 200 kDa to 250 kDa, 300 kDa to 400 kDa, or 300 kDa to 350 kDa.

In a further aspect, the method further includes the step of purifying the activated polysaccharide prior to step b). In a further aspect, the methods further include the step of adding a reducing agent after step b). In one aspect, the reducing agent is NaCNBH ₃ . In a further aspect, the methods further include the step of adding NaBH ₄ after adding NaCNBH ₃ . In a further aspect, the method includes a purification step after the addition of NaBH ₄ .

In another aspect, the present invention provides a glycoconjugate from S. pneumoniae serotype 12F, obtained, or can be obtained by any of the methods disclosed above in this document. For example, in one aspect, the present invention provides a glycoconjugate from S. pneumoniae serotype 12F containing a saccharide conjugated to a carrier protein, which is or can be obtained according to a method comprising the steps of: a) reacting the saccharide with 2,2,6,6- tetramethyl-1-piperidinyloxy (TEMPO) and N-chlorosuccinimide (NCS) in an aqueous solvent to give an activated saccharide; and b) reacting the activated saccharide with a carrier protein containing one or more amine groups.

In one embodiment, the S. pneumoniae serotype 12F glycoconjugate of the present invention has a molecular weight of from about 50 kDa to about 20,000 kDa. In another embodiment, the glycoconjugate has a molecular weight of from about 200 kD to about 10,000 kD. In another embodiment, the glycoconjugate from S. pneumoniae serotype 12F has a molecular weight of from about 500 kDa to about 5000 kDa. In one embodiment, the S. pneumoniae serotype 12F glycoconjugate has a molecular weight of about 1000 kDa to about 3000 kDa. In other embodiments, the implementation of the glycoconjugate from S. pneumoniae serotype 12F has a molecular weight from about 600 kDa to about 2800 kDa; from about 700 kDa to about 2700 kDa; from about 1000 kDa to about 2000 kDa; from about 1800 kDa to about 2500 kDa; from about 1100 kDa to about 2200 kDa; from about 1900 kDa to about 2700 kDa; from about 1200 kDa to about 2400 kDa; from about 1700 kDa to about 2600 kDa; from about 1300 kDa to about 2600 kDa; from about 1600 kDa to about 3000 kDa.

In further embodiments, the serotype 12F glycoconjugate of the invention has a molecular weight of 1000 kDa to 20,000 kDa; from 1000 kDa to 15000 kDa; from 1000 kDa to 10000 kDa; from 1000 kDa to 7500 kDa; from 1000 kDa to 5000 kDa; from 1000 kDa to 4000 kDa; from 1000 kDa to 3000 kDa; from 2000 kDa to 20000 kDa; from 2000 kDa to 15000 kDa; from 2000 kDa to 12500 kDa; from 2000 kDa to 10000 kDa; from 2000 kDa to 7500 kDa; from 2000 kDa to 6000 kDa; from 2000 kDa to 5000 kDa; from 2000 kDa to 4000 kDa; or from 2000 kDa to 3000 kDa. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention. In some such embodiments, the carrier protein is CRM ₁₉₇ . In some such embodiments, the serotype 12F glycoconjugate is conjugated to a carrier protein using TEMPO/NCS reductive amination.

Another way to characterize serotype 12F glycoconjugates of the invention is the number of lysine residues in the carrier protein (eg CRM ₁₉₇ ) that become conjugated to the saccharide, which can be characterized as a range of conjugated lysines (degree of conjugation).

In a preferred embodiment, the degree of conjugation of the serotype 12F glycoconjugate of the invention is 2 to 20, 4 to 16, 4 to 15, 2 to 15, 2 to 13, 2 to 10, 2 to 8, 2 to 6, 2 to 5, 2 to 4, 3 to 15, 3 to 13, 3 to 10, 3 to 8, 3 to 6, 3 to 5, 3 to 4, 5 up to 15, 5 to 10, 8 to 15, 8 to 12, 10 to 15, or 10 to 12. In one embodiment, the degree of conjugation of the serotype 12F glycoconjugate of the invention is about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, about 16, about 17, about 18, about 19, or about 20.

The number of lysine residues in a saccharide-conjugated carrier protein can also be expressed as a molar ratio. For example, in a glycoconjugate in which 4 to 15 CRM ₁₉₇ lysine residues are covalently linked to the saccharide, the molar ratio of CRM ₁₉₇ conjugated lysines in the glycoconjugate is from about 10:1 to about 40:1. In an immunogenic composition in which 2 to 20 CRM ₁₉₇ lysine residues are covalently linked to a saccharide, the molar ratio of CRM ₁₉₇ conjugated lysines in the glycoconjugate is from about 5:1 to about 50:1. In one embodiment, in the S. pneumoniae serotype 12F glycoconjugate of the present invention, the molar ratio of conjugated lysines to carrier protein is from about 10:1 to about 25:1. In some such embodiments, the carrier protein is CRM ₁₉₇ . In some embodiments, CRM ₁₉₇ may contain approximately 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 of the 39 lysine residues covalently linked to the saccharide. In some such embodiments, the serotype 12F glycoconjugate is conjugated to a carrier protein using TEMPO/NCS reductive amination.

In one embodiment, the ratio of saccharide to carrier protein (w/w) is 0.2 to 4 in the S. pneumoniae serotype 12F glycoconjugate (e.g., about 0.2, about 0.3, about 0.4 , approximately 0.5, approximately 0.6, approximately 0.7, approximately 0.8, approximately 0.9, approximately 1.0, approximately 1.1, approximately 1.2, approximately 1.3, approximately 1.4 , approximately 1.5, approximately 1.6, approximately 1.7, approximately 1.8, approximately 1.9, approximately 2.0, approximately 2.1, approximately 2.2, approximately 2.3, approximately 2.4 , approximately 2.5, approximately 2.6, approximately 2.7, approximately 2.8, approximately 2.9, approximately 3.0, approximately 3.1, approximately 3.2, approximately 3.3, approximately 3.4 , about 3.5, about 3.6, about 3.7, about 3.8, about 3.9, or about 4.0). In another embodiment, the ratio of saccharide to carrier protein (w/w) is 1.1 to 1.7 in a glycoconjugate from S. pneumoniae serotype 12F. In other embodiments, the ratio of saccharide to carrier protein (w/w) is 0.8 to 1.8 (e.g., about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, or about 1.8). In some such embodiments, the carrier protein is CRM ₁₉₇ . In some such embodiments, the carrier protein is CRM ₁₉₇ . In some such embodiments, the serotype 12F glycoconjugate is conjugated to a carrier protein using TEMPO/NCS reductive amination.

The frequency of saccharide chain attachments to lysine on the carrier protein is another parameter for characterizing serotype 12F glycoconjugates according to the disclosure. For example, in one embodiment, at least one covalent bond between the carrier protein and the polysaccharide is for every 100 saccharide repeat units of the polysaccharide. In one embodiment, there is at least one covalent bond between the carrier protein and the polysaccharide for every 50 saccharide repeating units of the polysaccharide. In one embodiment, at least one covalent bond between the carrier protein and the polysaccharide is for every 25 saccharide repeating units of the polysaccharide. In another embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 4 saccharide repeating units of the polysaccharide. In another embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 10 saccharide repeating units of the polysaccharide. In a further embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 15 saccharide repeat units of the polysaccharide. In numerous embodiments, the carrier protein is CRM ₁₉₇ and the covalent bond between CRM ₁₉₇ and the polysaccharide occurs at least once for every 4, 10, 15, or 25 saccharide repeat units of the polysaccharide.

In other embodiments, the conjugate contains at least a covalent bond between the carrier protein and the saccharide for every 5 to 10 saccharide repeat units; for every 2 to 7 saccharide repeat units; for every 3 to 8 saccharide repeat units; for every 4 to 9 saccharide repeat units; for every 6 to 11 saccharide repeat units; for every 7 to 12 saccharide repeat units; for every 8 to 13 saccharide repeat units; for every 9 to 14 saccharide repeat units; for every 10 to 15 saccharide repeat units; for every 2 to 6 saccharide repeat units, for every 3 to 7 saccharide repeat units; for every 4 to 8 saccharide repeat units; for every 6 to 10 saccharide repeat units; for every 7 to 11 saccharide repeat units; for every 8 to 12 saccharide repeat units; for every 9 to 13 saccharide repeat units; for every 10 to 14 saccharide repeat units; for every 10 to 20 saccharide repeat units; for every 4 to 25 saccharide repeat units, or for every 2 to 25 saccharide repeat units. In numerous embodiments, the carrier protein is CRM ₁₉₇ .

In another embodiment, at least a link between CRM ₁₉₇ and a saccharide occurs every 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 saccharide polysaccharide repeat units. In some such embodiments, the serotype 12F glycoconjugate is conjugated to a carrier protein using TEMPO/NCS reductive amination.

In one embodiment, the S. pneumoniae serotype 12F glycoconjugate of the invention contains at least a covalent bond between the carrier protein and the polysaccharide for every 25 polysaccharide saccharide repeat units. In another embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 4 saccharide repeat units of the polysaccharide. In another embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 10 saccharide repeating units of the polysaccharide. In a further embodiment, a covalent bond between the carrier protein and the polysaccharide occurs at least once for every 15 saccharide repeat units of the polysaccharide. In some such embodiments, the serotype 12F glycoconjugate is conjugated to a carrier protein using TEMPO/NCS reductive amination. Serotype 12F glycoconjugates and the immunogenic composition of the invention may contain a free saccharide that is not covalently conjugated to the carrier protein, but is nevertheless present in the glycoconjugate composition. The free saccharide may be non-covalently associated with (ie, non-covalently associated with, adsorbed to, or enclosed in or with) the glycoconjugate.

In some embodiments, the serotype 12F glycoconjugates of the invention contain less than about 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% free serotype 12F polysaccharide compared to with total polysaccharide serotype 12F. In one embodiment, the S. pneumoniae serotype 12F glycoconjugate contains less than about 50% free serotype 12F polysaccharide compared to the total serotype 12F polysaccharide. In one embodiment, the glycoconjugate from S. pneumoniae serotype 12F contains less than about 45% free serotype 12F polysaccharide compared to total serotype 12F polysaccharide. In another embodiment, the glycoconjugate contains less than about 30% free serotype 12F polysaccharide compared to the total serotype 12F polysaccharide. In another embodiment, the S. pneumoniae serotype 12F glycoconjugate contains less than about 20% free serotype 12F polysaccharide compared to the total serotype 12F polysaccharide. In a further embodiment, the glycoconjugate contains less than about 10% free serotype 12F polysaccharide compared to total serotype 12F polysaccharide. In another embodiment, the S. pneumoniae serotype 12F glycoconjugate contains less than about 5% free serotype 12F polysaccharide compared to total serotype 12F polysaccharide. In some such embodiments, the serotype 12F glycoconjugate is conjugated to a carrier protein using TEMPO/NCS reductive amination.

In some embodiments, the 12F serotype glycoconjugate of the present invention comprises a saccharide having a molecular weight of 10 kDa to 2000 kDa. In other such embodiments, the saccharide has a molecular weight of 50 kDa to 2000 kDa. In further such embodiments, the saccharide has a molecular weight of 50 kDa to 1750 kDa; from 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 1750 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1750 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa; or from 200 kDa to 400 kDa. In some such embodiments, the serotype 12F glycoconjugate is conjugated to a carrier protein using TEMPO/NCS reductive amination.

Serotype 12F glycoconjugates can also be characterized by their molecular size distribution (K _d ). Gel Permeation Media Chromatography (CL-4B) can be used to determine the relative molecular size distribution of the conjugate as indicated above.

In a preferred embodiment, at least 35% of the serotype 12F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85% of the serotype 12F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 60% of the serotype 12F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 70% of the serotype 12F glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column.

In a preferred embodiment, 40% to 90% of serotype 12F glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 50% to 90% of serotype 12F glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 65% to 80% of serotype 12F glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column.

1.3.6. Glycoconjugates from S. pneumoniae serotype 10A

In one embodiment, serotype 10A glycoconjugates are prepared by activating the polysaccharide with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) to form a cyanate ester. The activated polysaccharide can be attached directly or through a spacer (linker) group to the amino group on the carrier protein. For example, the spacer may be a cystamine or cysteamine yielding a thiolated polysaccharide that can be attached to the carrier via a thioether bond formed after reaction with a maleimide-activated carrier protein (e.g. using GMBS) or a haloacetylated carrier protein (e.g. using iodoacetamide , SIB, SIAB, sulfo-SIAB, SIA, or SBAP). Preferably, the cyanate ester (optionally prepared using CDAP chemistry) is coupled to hexanediamine or adipic acid hydrazide (ADH) and the amino-derivatized saccharide is conjugated to the carrier protein using carbodiimide (e.g., EDAC or EDC) chemistry through the carboxyl group on the protein. carrier. Such conjugates are described, for example, in WO 93/15760, WO 95/08348 and WO 96/129094.

Other suitable methods use carbodiimides, hydrazides, active esters, norborane, p-nitrobenzoic acid, N-hydroxysuccinimide, S-NHS, EDC, TSTU. Many of them are described in International Patent Publication No. WO 98/42721. The conjugation may include a carbonyl linker which may be formed by the reaction of the free hydroxyl group of the saccharide with CDI (see Bethell et al. (1979) J. Biol. Chern. 254:2572-2574; Hearn et al. (1981) J. Chromatogr, 218: 509-518), followed by reaction with the protein to form a carbamate bond. This may include reducing the anomeric end to a primary hydroxyl group, optionally protecting/deprotecting the primary hydroxyl group, reacting the primary hydroxyl group with a CDI to form a CDI carbamate intermediate, and reacting a CDI carbamate intermediate with an amino group on a protein.

In preferred embodiments, the serotype 10A glycoconjugates of the invention are prepared using reductive amination. Reductive amination involves two steps, (1) oxidation of the polysaccharide to form aldehyde functional groups from vicinal diols in the individual hexasaccharide unit, (2) reduction of the activated polysaccharide and carrier protein to form a conjugate.

Prior to oxidation, the serotype 10A polysaccharide is optionally hydrolyzed (sorted by size). Mechanical or chemical hydrolysis may be used. Chemical hydrolysis can be carried out using acetic acid.

In one embodiment, the polysaccharide serotype is activated (oxidized) according to a method comprising the step of:

(a) reacting the isolated serotype 10A polysaccharide with an oxidizing agent;

(b) quenching the oxidative reaction by adding a quenching agent, resulting in an activated serotype 10A polysaccharide.

In a preferred embodiment, the oxidizing agent is a periodate. For the purposes of the present invention, the term "periodate" includes both periodate and periodic acid, the term also includes both metaperiodate (IO ₄ ^- ) and orthoperiodate (IO ₆ ^5- ) and various salts of periodate (for example, sodium periodate and potassium periodat). In a preferred embodiment, the oxidizing agent is sodium periodate. In a preferred embodiment, the periodate used to oxidize the serotype 10A polysaccharide is metaperiodate. In a preferred embodiment, the periodate used to oxidize the serotype 10A polysaccharide is sodium metaperiodate.

In one embodiment, the quenching agent is selected from vicinal diols, 1,2-amino alcohols, amino acids, glutathione, sulfite, bisulfate, dithionite, metabisulfite, thiosulfate, phosphites, hypophosphites, or phosphorous acid.

In one embodiment, the quenching agent is 1,2-amino alcohols of formula (I):

where R ¹ is selected from H, methyl, ethyl, propyl or isopropyl.

In one embodiment, the quenching agent is selected from sodium and potassium salts of sulfite, bisulfate, dithionite, metabisulfite, thiosulfate, phosphites, hypophosphites, or salts of phosphorous acid.

In one embodiment, the quenching agent is an amino acid. In such embodiments, said amino acid may be selected from serine, threonine, cysteine, cystine, methionine, proline, hydroxyproline, tryptophan, tyrosine, and histidine.

In one embodiment, the quenching agent is a sulfite such as bisulfate, dithionite, metabisulfite, thiosulfate.

In one embodiment, the quenching agent is a compound containing two vicinal hydroxyl groups (vicinal diols), that is, two hydroxyl groups covalently bonded to two adjacent carbon atoms.

Preferably, the quenching agent is a compound of formula (II):

where R ¹ and R ² are each independently selected from H, methyl, ethyl, propyl or isopropyl.

In a preferred embodiment, the quenching agent is glycerin, ethylene glycol, propane-1,2-diol, butane-1,2-diol or butane-2,3-diol, ascorbic acid. In a preferred embodiment, the quenching agent is butane-2,3-diol.

In a preferred embodiment, the isolated serotype 10A polysaccharide is activated according to a method comprising the step of:

(a) interactions of the isolated serotype 10A polysaccharide with periodate;

(b) quenching the oxidative reaction by adding butane-2,3-diol, resulting in activated serotype 10A polysaccharide.

After the polysaccharide oxidation step, the polysaccharide is said to be activated and hereinafter referred to as "activated polysaccharide".

In a preferred embodiment, the activated serotype 10A polysaccharide is purified. Activated serotype 10A polysaccharide is purified according to methods known to those skilled in the art such as gel permeation chromatography (GPC), dialysis, or ultrafiltration/diafiltration. For example, activated polysaccharide 10A is purified by concentration and diafiltration using an ultrafiltration device.

In a preferred embodiment, the oxidation state of the activated serotype 10A polysaccharide is 2 to 30, 2 to 25, 2 to 20, 2 to 15, 2 to 10, 2 to 5, 5 to 30, 5 to 25 , 5 to 20, 5 to 15, 5 to 10, 10 to 30, 10 to 25, 10 to 20, 10 to 15, 15 to 30, 15 to 25, 15 to 20 , 20 to 30, or 20 to 25. In a preferred embodiment, the oxidation state of the activated serotype 10A polysaccharide is 2 to 10, 4 to 8, 4 to 6, 6 to 8, 6 to 12, 8 to 14, 9 to 11, 10 to 16, 12 to 16, 14 to 18, 16 to 20, 16 to 18, 18 to 22, or 18 to 20.

In a preferred embodiment, the activated serotype 10A polysaccharide has a molecular weight of 50 kDa to 400 kDa, 50 kDa to 350 kDa, 50 kDa to 300 kDa, 50 kDa to 250 kDa, 50 kDa to 200 kDa, 100 kDa up to 300 kDa, from 100 kDa to 250 kDa, or from 100 kDa to 200 kDa. In a preferred embodiment, the activated serotype 10A polysaccharide has a molecular weight of 50 kDa to 300 kDa. In a preferred embodiment, the activated serotype 10A polysaccharide has a molecular weight of 100 kDa to 200 kDa. In a preferred embodiment, the activated serotype 10A polysaccharide has a molecular weight of 100 kDa to 200 kDa and an oxidation state of 5 to 20, 5 to 15, 8 to 14, 8 to 12, or 9 to 11. In a preferred embodiment, , activated serotype 10A polysaccharide has a molecular weight of 100 kDa to 200 kDa and an oxidation state of 9 to 11.

The activated polysaccharide and/or carrier protein may be lyophilized (freeze-dried), either independently (lyophilized separately) or together (co-lyophilized). In one embodiment, the activated serotype 10A polysaccharide is lyophilized, optionally in the presence of a saccharide. In a preferred embodiment, the saccharide is selected from sucrose, trehalose, raffinose, stachyose, melecytose, dextran, mannitol, lactitol and palatinite. In a preferred embodiment, the saccharide is sucrose. In one embodiment, the lyophilized activated polysaccharide is then mixed with a solution containing a carrier protein.

In another embodiment, the activated polysaccharide and carrier protein are co-lyophilized. In such embodiments, the activated serotype 10A polysaccharide is mixed with a carrier protein and optionally lyophilized in the presence of the saccharide. In a preferred embodiment, the saccharide is selected from sucrose, trehalose, raffinose, stachyose, melecytose, dextran, mannitol, lactitol and palatinite. In a preferred embodiment, the saccharide is sucrose. The co-lyophilized polysaccharide and carrier protein can then be resuspended in solution and reacted with a reducing agent.

The second step of the conjugation process is the reduction of the activated polysaccharide and carrier protein to form a conjugate (reductive amination), using a reducing agent.

The activated serotype 10A polysaccharide may be conjugated to a carrier protein according to a method comprising the step of:

(c) mixing the activated serotype 10A polysaccharide with a carrier protein; and

(d) reacting the compounded activated serotype 10A polysaccharide and carrier protein with a reducing agent to form a serotype 10A polysaccharide-carrier protein conjugate.

In one embodiment, the reduction reaction is carried out in an aqueous solvent, in another embodiment, the reaction is carried out in an aprotic solvent. In one embodiment, the reduction reaction is carried out in DMSO (dimethyl sulfoxide) or DMF (dimethylformamide) solvent. DMSO or DMF solvent can be used to reconstitute the activated polysaccharide and carrier protein that have been lyophilized.

In one embodiment, the reducing agent is sodium cyanoborohydride, sodium triacetoxyborohydride, sodium or zinc borohydride in the presence of Bronsted or Lewis acids, aminoboranes such as pyridine-borane, 2-picoline-borane, 2,6-diborane-methanol, dimethylamine- borane, t-BuMeiPrN-BH ₃ , benzylamine-BH3 or 5-ethyl-2-methylpyridine-borane (PEMB). In a preferred embodiment, the reducing agent is sodium cyanoborohydride.

At the end of the reduction reaction, unreacted aldehyde groups may remain in the conjugates and may be blocked with a suitable blocking agent. In one embodiment, this blocking agent is sodium borohydride (NaBH ₄ ).

After the serotype 10A polysaccharide has been conjugated to a carrier protein, the glycoconjugate can be purified (enriched relative to the amount of polysaccharide-protein conjugate) using a variety of methods known to the skilled artisan. These methods include dialysis, concentration/diafiltration operations, tangential flow filtration, settling/elution, column chromatography (DEAE or hydrophobic interaction chromatography), and depth filtration.

In some embodiments, the serotype 10A glycoconjugates of the present invention comprise a saccharide having a molecular weight of 10 kDa to 2000 kDa. In other such embodiments, the saccharide has a molecular weight of 50 kDa to 2000 kDa. In further such embodiments, the saccharide has a molecular weight of 50 kDa to 1750 kDa; from 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 1750 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1750 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa; or from 200 kDa to 400 kDa. In some such embodiments, serotype 10A glycoconjugates are prepared using reductive amination.

In some embodiments, the serotype 10A glycoconjugate of the invention has a molecular weight of 50 kDa to 20,000 kDa. In other embodiments, the serotype 10A glycoconjugate has a molecular weight of 50 kDa to 15,000 kDa. In other embodiments, the serotype 10A glycoconjugate has a molecular weight of 500 kDa to 15,000 kDa, 500 kDa to 10,000 kDa; from 2000 kDa to 10000 kDa; or from 3000 kDa to 8,000 kDa. In other embodiments, the serotype 10A glycoconjugate has a molecular weight of 1000 kDa to 10,000 kDa. In other embodiments, the serotype 10A glycoconjugate has a molecular weight of 1000 kDa to 8000 kDa. In yet other embodiments, the serotype 10A glycoconjugate has a molecular weight of 2000 kDa to 8000 kDa, or 3000 kDa to 7000 kDa. In further embodiments, the serotype 10A glycoconjugate of the invention has a molecular weight of 200 kDa to 20,000 kDa; from 200 kDa to 15000 kDa; from 200 kDa to 10,000 kDa; from 200 kDa to 7500 kDa; from 200 kDa to 5000 kDa; from 200 kDa to 3000 kDa; from 200 kDa to 1000 kDa; from 500 kDa to 20,000 kDa; from 500 kDa to 15000 kDa; from 500 kDa to 12500 kDa; from 500 kDa to 10,000 kDa; from 500 kDa to 7500 kDa; from 500 kDa to 6000 kDa; from 500 kDa to 5000 kDa; from 500 kDa to 4000 kDa; from 500 kDa to 3000 kDa; from 500 kDa to 2000 kDa; from 500 kDa to 1500 kDa; from 500 kDa to 1000 kDa; from 750 kDa to 20,000 kDa; from 750 kDa to 15000 kDa; from 750 kDa to 12500 kDa; from 750 kDa to 10000 kDa; from 750 kDa to 7500 kDa; from 750 kDa to 6000 kDa; from 750 kDa to 5000 kDa; from 750 kDa to 4000 kDa; from 750 kDa to 3000 kDa; from 750 kDa to 2000 kDa; from 750 kDa to 1500 kDa; from 1000 kDa to 15000 kDa; from 1000 kDa to 12500 kDa; from 1000 kDa to 10000 kDa; from 1000 kDa to 7500 kDa; from 1000 kDa to 6000 kDa; from 1000 kDa to 5000 kDa; from 1000 kDa to 4000 kDa; from 1000 kDa to 2500 kDa; from 2000 kDa to 15000 kDa; from 2000 kDa to 12500 kDa; from 2000 kDa to 10000 kDa; from 2000 kDa to 7500 kDa; from 2000 kDa to 6000 kDa; from 2000 kDa to 5000 kDa; from 2000 kDa to 4000 kDa; or from 2000 kDa to 3000 kDa.

In further embodiments, the serotype 10A glycoconjugate of the invention has a molecular weight of 3,000 kDa to 20,000 kDa; from 3000 kDa to 15000 kDa; from 3000 kDa to 10000 kDa; from 3000 kDa to 7500 kDa; from 3000 kDa to 5000 kDa; from 4000 kDa to 20000 kDa; from 4000 kDa to 15000 kDa; from 4000 kDa to 12500 kDa; from 4000 kDa to 10000 kDa; from 4000 kDa to 7500 kDa; from 4000 kDa to 6000 kDa; or from 4000 kDa to 5000 kDa. In further embodiments, the serotype 10A glycoconjugate of the invention has a molecular weight of 5,000 kDa to 20,000 kDa; from 5000 kDa to 15000 kDa; 5000 kDa to 10000 kDa or 5000 kDa to 7500 kDa. In further embodiments, the serotype 10A glycoconjugate of the invention has a molecular weight of 6,000 kDa to 20,000 kDa; from 6000 kDa to 15000 kDa; 6000 kDa to 10000 kDa or 6000 kDa to 7500 kDa. In further embodiments, the serotype 10A glycoconjugate according to the invention has a molecular weight of 7,000 kDa to 20,000 kDa; from 7000 kDa to 15000 kDa; 7000 kDa to 10000 kDa or 7000 kDa to 8000 kDa. In further embodiments, the serotype 10A glycoconjugate of the invention has a molecular weight of 8,000 kDa to 20,000 kDa; from 8000 kDa to 15000 kDa; or from 8000 kDa to 10000 kDa.

Any integer integer within any of the ranges above is contemplated as an embodiment of the invention. The molecular weight of the glycoconjugate is measured using SEC-MALLS.

Another way to characterize serotype 10A glycoconjugates of the invention is the number of lysine residues in the carrier protein (e.g. CRMw) that become conjugated to the saccharide, which can be characterized as a range of conjugated lysines (degree of conjugation). Evidence of a lysine modification of the carrier protein, due to covalent bonds with polysaccharides, can be obtained by amino acid analysis using standard methods known to those skilled in the art. The conjugation results in a reduction in the amount of reduced lysine residues compared to the original CRM ₁₉₇ protein material used to form the conjugate materials.

In a preferred embodiment, the degree of conjugation of the serotype 10A glycoconjugate is 2 to 15, 2 to 13, 2 to 10, 2 to 8, 2 to 6, 2 to 5, 2 to 4, 3 to 15 , 3 to 13, 3 to 10, 3 to 8, 3 to 6, 3 to 5, 3 to 4, 5 to 15, 5 to 10, 8 to 15, 8 to 12 , 10 to 15, or 10 to 12. In a preferred embodiment, the degree of conjugation of the serotype 10A glycoconjugate is 6 to 8. In a preferred embodiment, the carrier protein is CRM ₁₉₇

Serotype 10A glycoconjugates of the invention can also be characterized by the ratio (w/w) of saccharide to carrier protein. In some embodiments, the ratio of saccharide to carrier protein (w/w) is 0.5 to 3.0 (e.g., about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, about 1.8, about 1.9, about 2.0, about 2.1, about 2.2, about 2.3, about 2.4, about 2.5, about 2.6, about 2.7, about 2.8, about 2.9 or about 3.0). In a preferred embodiment, the ratio of serotype 10A saccharide to carrier protein in the conjugate is 0.5 to 2.0, 0.5 to 1.5, 0.5 to 1.0, 1.0 to 1, 5 or 1.0 to 2.0. In a preferred embodiment, the ratio of serotype 10A polysaccharide to carrier protein in the conjugate is between 0.8 and 1.4. In a preferred embodiment, the ratio of serotype 10A capsular polysaccharide to carrier protein in the conjugate is 0.8 to 1.2 (e.g., about 0.8, about 0.9, about 1.0, about 1.1, or about 1 ,2). In some such embodiments, the carrier protein is CRM ₁₉₇ .

Serotype 10A glycoconjugates and the immunogenic composition of the invention may contain a free saccharide which is not covalently conjugated to the carrier protein but is nevertheless present in the glycoconjugate composition. The free saccharide may be non-covalently associated with (ie, non-covalently associated with, adsorbed to, or enclosed in or with) the glycoconjugate.

In some embodiments, the serotype 10A glycoconjugates of the invention contain less than about 50% Free saccharide, less than about 45% Free saccharide, less than about 40% Free saccharide, less than about 35% Free saccharide, less than less than about 30% Free saccharide, less than about 25% Free saccharide, less than about 20% Free saccharide, less than about 15% Free saccharide, less than about 10% Free saccharide, or less than about 5% Free saccharide relative to total saccharide 10A. Preferably, the serotype 10A glycoconjugate contains less than 15% Free saccharide, more preferably less than 10% Free saccharide, and even more preferably less than 5% Free saccharide.

Serotype 10A glycoconjugates can also be characterized by their molecular size distribution (K _d ). Gel Permeation Media Chromatography (CL-4B) can be used to determine the relative molecular size distribution of the conjugate as described above.

In a preferred embodiment, at least 30% of the serotype 10A glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 40% of the serotype 10A glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85% of the serotype 10A glycoconjugates of the invention have a K _d less than or equal to 0.3 in column CL-4B. In a preferred embodiment, at least 60% of the serotype 10A glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 50% to 80% of the serotype 10A glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column.

1.3.7. Glycoconjugates from S. pneumoniae serotype 11A

In one embodiment, serotype 11A glycoconjugates are prepared by activating the polysaccharide with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) to form a cyanate ester. The activated polysaccharide can be attached directly or through a spacer (linker) group to the amino group on the carrier protein. For example, the spacer can be a cystamine or a cysteamine yielding a thiolated polysaccharide that can be attached to the carrier via a thioether bond formed after reaction with a maleimide-activated carrier protein (e.g., using GMBS) or a haloacetylated carrier protein (e.g., using iodoacetamide, SIB, SIAB, sulfo-SIAB, SIA, or SBAP). Preferably, the cyanate ester (optionally prepared using CDAP chemistry) is coupled to hexanediamine or adipic acid hydrazide (ADH) and the amino-derivatized saccharide is conjugated to the carrier protein using carbodiimide (e.g., EDAC or EDC) chemistry through the carboxyl group on the protein. carrier. Such conjugates are described, for example, in WO 93/15760, WO 95/08348 and WO 96/129094.

Other suitable methods use carbodiimides, hydrazides, active esters, norborane, p-nitrobenzoic acid, N-hydroxysuccinimide, S-NHS, EDC, TSTU. Many of these are described in International Patent Publication No. WO 98/42721. The conjugation may include a carbonyl linker which may be formed by the reaction of the free hydroxyl group of the saccharide with CDI (see Bethell et al. (1979). Biol. Chern. 254: 2572-2574; Hearn et al. (1981) J. Chromatogr, 218 : 509-518) followed by reaction with the protein to form a carbamate bond. This may include reducing the anomeric end to a primary hydroxyl group, optionally protecting/deprotecting the primary hydroxyl group, reacting the primary hydroxyl group with a CDI to form a CDI carbamate intermediate, and reacting a CDI carbamate intermediate with an amino group on a protein.

In preferred embodiments, the serotype 11A glycoconjugates of the invention are prepared using reductive amination. Reductive amination involves two steps, (1) oxidation of the polysaccharide to form aldehyde functional groups from vicinal diols in the individual hexasaccharide unit, (2) reduction of the activated polysaccharide and carrier protein to form a conjugate.

Prior to oxidation, the serotype 11A polysaccharide is optionally hydrolysed in order to reduce its viscosity. Mechanical or chemical hydrolysis may be used. Chemical hydrolysis can be carried out using acetic acid. Mechanical sizing can be carried out using fragmentation by high pressure homogenization.

The oxidation step may include reaction with periodate. For the purposes of the present invention, the term "periodate" includes both periodate and periodic acid; the term also includes both metaperiodate (IO ₄ ^- ) and orthoperiodate (IO ₆ ^5- ) and various periodate salts (eg, sodium periodate and potassium periodate). In one embodiment, the serotype 11A capsular polysaccharide from S. pneumoniae is oxidized in the presence of metaperiodate, preferably in the presence of sodium periodate (NaIO ₄ ). In another embodiment, the serotype 11A capsular polysaccharide is oxidized in the presence of orthoperiodate, preferably in the presence of periodic acid.

After the step of oxidizing the polysaccharide, the polysaccharide is said to be activated and hereinafter referred to as "activated polysaccharide". The activated polysaccharide can be purified and lyophilized (freeze-dried).

The activated polysaccharide and carrier protein may be lyophilized (freeze-dried), or independently (lyophilized separately) or together (co-lyophilized). In one embodiment, the activated polysaccharide and carrier protein are co-lyophilized. In another embodiment, the activated polysaccharide and carrier protein are lyophilized independently of each other.

In one embodiment, lyophilization occurs in the presence of a non-reducing sugar, possibly non-reducing sugars include sucrose, trehalose, raffinose, stachyose, melecytose, dextran, mannitol, lactitol, and palatinite.

The second step of the conjugation process is the reduction of the activated polysaccharide and carrier protein to form a conjugate (reductive amination), using a reducing agent. Reducing agents that are suitable include cyanoborohydrides such as sodium cyanoborohydride, borane pyridine, or borohydride exchange resin. In one embodiment, the reducing agent is sodium cyanoborohydride.

In one embodiment, the reduction reaction is carried out in an aqueous solvent, in another embodiment, the reaction is carried out in an aprotic solvent. In one embodiment, the reduction reaction is carried out in DMSO (dimethyl sulfoxide) or DMF (dimethylformamide) as a solvent. DMSO or DMF solvent can be used to reconstitute the activated polysaccharide and carrier protein that have been lyophilized.

In one embodiment, 0.1 to 3.0, 0.15 to 2.0, 0.2 to 2.0, or 0.5 to 1.5 molar equivalents of sodium cyanoborohydride is used in the reduction reaction. In one embodiment, approximately 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1 .3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5 , 2.6, 2.9, or 3.0 molar equivalents of sodium cyanoborohydride are used in the reduction reaction.

In one embodiment, the reducing agent is sodium triacetoxyborohydride, in the following embodiment, 1.0 to 6.0 molar equivalents, 2.0 to 5.0 molar equivalents, or about 3.0 molar equivalents of sodium triacetoxyborohydride is used in the reduction reaction.

At the end of the reduction reaction, unreacted aldehyde groups may remain in the conjugates and may be blocked with a suitable blocking agent. In one embodiment, this blocking agent is sodium borohydride (NaBH ₄ ). In one embodiment, blocking is achieved by mixing the reduction reaction with 0.5 to 5.0 molar equivalents of NaBH ₄ , eg, about 1, 1.5, 2, 2.5, or 3 molar equivalents of NaBH ₄ .

After conjugation (reduction reaction and optionally blocking), the glycoconjugates can be purified. Glycoconjugates can be purified using diafiltration and/or ion exchange chromatography and/or gel permeation chromatography. In one embodiment, the glycoconjugates are purified using diafiltration and/or ion exchange chromatography and/or gel permeation chromatography.

In one embodiment, the glycoconjugates are subjected to sterilizing filtration.

In some embodiments, the serotype 11A glycoconjugates of the present invention are conjugated to a carrier protein (eg, CRM ₁₉₇ ) and contain a saccharide having a molecular weight of 10 kDa to 2000 kDa. In other such embodiments, the saccharide has a molecular weight of 50 kDa to 2000 kDa. In further such embodiments, the saccharide has a molecular weight of 50 kDa to 1750 kDa; from 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 50 kDa to 400 kDa; from 50 kDa to 300 kDa; from 50 kDa to 200 kDa; from 50 kDa to 100 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 1750 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 100 kDa to 400 kDa from; from 100 kDa to 300 kDa; from 100 kDa to 200 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1750 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa; 200 kDa to 400 kDa or 200 kDa to 300 kDa.

In some embodiments, the serotype 11A glycoconjugate of the invention has a molecular weight of 50 kDa to 20,000 kDa. In other embodiments, the serotype 11A glycoconjugate has a molecular weight of 50 kDa to 15,000 kDa. In other embodiments, the serotype 11A glycoconjugate has a molecular weight of 500 kDa to 10,000 kDa. In other embodiments, the serotype 11A glycoconjugate has a molecular weight of 200 kDa to 10,000 kDa. In still other embodiments, the serotype 11A glycoconjugate has a molecular weight of 1000 kDa to 8000 kDa or 2000 kDa to 8000 kDa.

In further embodiments, the serotype 11A glycoconjugate of the invention has a molecular weight of 200 kDa to 20,000 kDa; from 200 kDa to 17500 kDa; from 200 kDa to 15000 kDa; from 200 kDa to 10,000 kDa; from 200 kDa to 7500 kDa; from 200 kDa to 5000 kDa; from 200 kDa to 3000 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1000 kDa; from 500 kDa to 20,000 kDa; from 500 kDa to 17500 kDa; from 500 kDa to 15000 kDa; from 500 kDa to 12500 kDa; from 500 kDa to 10,000 kDa; from 500 kDa to 7500 kDa; from 500 kDa to 6000 kDa; from 500 kDa to 5000 kDa; from 500 kDa to 4000 kDa; from 500 kDa to 3000 kDa; from 500 kDa to 2000 kDa; from 500 kDa to 1500 kDa; from 500 kDa to 1000 kDa; from 700 kDa to 20,000 kDa; from 700 kDa to 17500 kDa; from 700 kDa to 15000 kDa; from 700 kDa to 12500 kDa; from 700 kDa to 10,000 kDa; from 700 kDa to 7500 kDa; from 700 kDa to 6000 kDa; from 700 kDa to 5000 kDa; from 700 kDa to 4500 kDa; from 700 kDa to 4000 kDa; from 700 kDa to 3500 kDa; from 700 kDa to 3000 kDa; from 700 kDa to 2000 kDa; from 700 kDa to 1500 kDa; from 1000 kDa to 20000 kDa; from 1000 kDa to 17500 kDa; from 1000 kDa to 15000 kDa; from 1000 kDa to 12500 kDa; from 1000 kDa to 10000 kDa; from 1000 kDa to 7500 kDa; from 1000 kDa to 6000 kDa; from 1000 kDa to 5000 kDa; from 1000 kDa to 4000 kDa; from 1000 kDa to 2500 kDa; from 2000 kDa to 20000 kDa; from 2000 kDa to 17500 kDa; from 2000 kDa to 15000 kDa; from 2000 kDa to 12500 kDa; from 2000 kDa to 10000 kDa; from 2000 kDa to 7500 kDa; from 2000 kDa to 6000 kDa; from 2000 kDa to 5000 kDa; from 2000 kDa to 4000 kDa; or from 2000 kDa to 3000 kDa.

In one embodiment, said serotype 11A glycoconjugate is prepared using reductive amination.

In a preferred embodiment, the serotype 11A glycoconjugate according to the invention contains at least 0.3, 0.5, 0.6, 1.0, 1.4, 1.8, 2.2, 2.6, 3, 0, 3.4, 3.8, 4.2, 4.6, or 5 mM acetate per mM serotype 11A polysaccharide. In a preferred embodiment, the serotype 11A glycoconjugate contains at least 1.8, 2.2, or 2.6 mM acetate per mM serotype 11A polysaccharide. In one embodiment, the glycoconjugate contains at least 0.6 mM acetate per mM serotype 11A polysaccharide. In a preferred embodiment, the serotype 11A glycoconjugate according to the invention contains at least 0.6, 1, 1.4, 1.8, 2.2, 2.6, 3, 3.4, 3.8, 4, 2 or 4.6 mM acetate per mM serotype 11A polysaccharide and less than about 5 mM acetate per mM serotype 11A polysaccharide. In one embodiment, the serotype 11A glycoconjugate of the invention contains at least 0.6, 1.0, 1.4, 1.8, 2.2, 2.6, or 3.0 mM acetate per mM serotype polysaccharide 11A and less than about 3.4 mM acetate per mM serotype 11A polysaccharide. In one embodiment, the serotype 11A glycoconjugate of the invention contains at least 0.6, 1, 1.4, 1.8, 2.2, 2.6, or about 3.0 mM acetate per mM serotype 11A polysaccharide , and less than about 3.3 mM acetate per mM serotype 11A polysaccharide. Any of the above amount is contemplated as an embodiment of the invention.

In a preferred embodiment, the ratio of mM acetate per mM serotype 11A capsular polysaccharide in the serotype 11A glycoconjugate to mM acetate per mM serotype 11A capsular polysaccharide in the isolated polysaccharide is at least 0.6, 0.65, 0.7, 0, 75, 0.8, 0.85, 0.9, or 0.95. In a preferred embodiment, the ratio of mM acetate per mM serotype 11A capsular polysaccharide in the serotype 11A glycoconjugate to mM acetate per mM serotype 11A capsular polysaccharide in the isolated polysaccharide is at least 0.7. In a preferred embodiment, the ratio of mM acetate per mM serotype 11A capsular polysaccharide in the serotype 11A glycoconjugate to mM acetate per mM serotype 11A capsular polysaccharide in the isolated polysaccharide is at least 0.9. In a preferred embodiment, the presence of O-acetyl groups is determined using ion-HPLC analysis.

In a preferred embodiment, the ratio of mM acetate per mM serotype 11A capsular polysaccharide in the serotype 11A glycoconjugate to mM acetate per mM serotype 11A capsular polysaccharide in the activated polysaccharide is at least 0.6, 0.65, 0.7, 0, 75, 0.8, 0.85, 0.9, or 0.95. In a preferred embodiment, the ratio of mM acetate per mM serotype 11A capsular polysaccharide in the serotype 11A glycoconjugate to mM acetate per mM serotype 11A capsular polysaccharide in the activated polysaccharide is at least 0.7. In a preferred embodiment, the ratio of mM acetate per mM serotype 11A capsular polysaccharide in the serotype 11A glycoconjugate to mM acetate per mM serotype 11A capsular polysaccharide in the activated polysaccharide is at least 0.9. In a preferred embodiment, the presence of O-acetyl groups is determined using ion-HPLC analysis.

In a preferred embodiment, the serotype 11A glycoconjugate according to the invention contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0, 9 or 1.0 mM glycerol per mM serotype 11A polysaccharide. In a preferred embodiment, the serotype 11A glycoconjugate contains at least 0.2, 0.3, or 0.4 mM glycerol per mM serotype 11A polysaccharide. In a preferred embodiment, the serotype 11A glycoconjugate according to the invention contains at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0. 9 mM glycerol per mM serotype 11A polysaccharide and less than about 1.0 mM glycerol per mM serotype 11A polysaccharide. In a preferred embodiment, the serotype 11A glycoconjugate of the invention contains at least 0.3, 0.4, 0.5, 0.6, or 0.7 mM glycerol per mM serotype 11A polysaccharide and less than about 0. 8 mM glycerol per mM serotype 11A polysaccharide. Any of the above amount is contemplated as an embodiment of the invention.

Another way to characterize serotype 11A glycoconjugates of the invention is the number of lysine residues in the carrier protein (eg CRM ₁₉₇ ) that become conjugated to the saccharide, which can be characterized as the range of conjugated lysines (degree of conjugation).

Evidence of a lysine modification of the carrier protein, due to covalent bonds with polysaccharides, can be obtained by amino acid analysis using standard methods known to those skilled in the art. The conjugation results in a reduction in the amount of reduced lysine residues compared to the original CRM197 protein material used to form the conjugate materials.

In a preferred embodiment, the degree of conjugation of the serotype 11A glycoconjugate of the invention is 1 to 15, 1 to 13, 1 to 10, 1 to 8, 1 to 6, 1 to 5, 1 to 4, 2 to 15, 2 to 13, 2 to 10, 2 to 8, 2 to 6, 2 to 5, 2 to 4, 5 to 15, 5 to 10, 8 to 15, 8 up to 12, 10 to 15, or 10 to 12. In one embodiment, the degree of conjugation of the serotype 11A glycoconjugate of the invention is about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, or about 15. In a preferred embodiment, the degree of conjugation of the serotype 11A glycoconjugate of the invention is 1 to 6, or 2 to 5. In some such embodiments, the carrier protein is CRM ₁₉₇ .

The serotype 11A glycoconjugates of the invention can also be characterized by the ratio (w/w) of saccharide to carrier protein. In some embodiments, the ratio of saccharide to carrier protein (w/w) is 0.2 to 4 (e.g., about 0.2, about 0.3, about 0.4, about 0.5, about 0 .6, approximately 0.7, approximately 0.8, approximately 0.9, approximately 1.0, approximately 1.1, approximately 1.2, approximately 1.3, approximately 1.4, approximately 1.5, approximately 1 .6, approximately 1.7, approximately 1.8, approximately 1.9, approximately 2.0, approximately 2.1, approximately 2.2, approximately 2.3, approximately 2.4, approximately 2.5, approximately 2 .6, approximately 2.7, approximately 2.8, approximately 2.9, approximately 3.0, approximately 3.1, approximately 3.2, approximately 3.3, approximately 3.4, approximately 3.5, approximately 3.6 , about 3.7, about 3.8, about 3.9, or about 4.0). In other embodiments, the ratio of saccharide to carrier protein (w/w) is 0.7 to 2.5, 0.8 to 2.0, 0.7 to 2.0, 0.8 to 1.5, 0.7 to 1.5, 0.7 to 1.4, 0.8 to 1.4, 0.7 to 1.45 or 0.8 to 1.45. In the following embodiments, the ratio of saccharide to carrier protein (w/w) is 0.8 to 1.6 (e.g., about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, or about 1.6). In some such embodiments, the carrier protein is CRM ₁₉₇ . In one embodiment, said serotype 11A glycoconjugates are prepared using reductive amination.

Serotype 11A glycoconjugates and the immunogenic composition of the invention may contain a free saccharide that is not covalently conjugated to the carrier protein, but is nonetheless present in the glycoconjugate composition. The free saccharide may be non-covalently associated with (ie, non-covalently associated with, adsorbed to, or enclosed in or with) the glycoconjugate.

In some embodiments, the serotype 11A glycoconjugates of the invention contain less than about 50% free serotype 11A capsular polysaccharide compared to total serotype 11A capsular polysaccharide, less than about 45% Free saccharide, less than about 40% Free saccharide, less than about 35% Free saccharide, less than about 30% Free saccharide, less than about 25% Free saccharide, less than about 20% Free saccharide, less than about 15% Free saccharide, less than about 10 % Free saccharide, or less than about 5% free serotype 11A capsular polysaccharide compared to total serotype 11A capsular polysaccharide. Preferably, the serotype 11A glycoconjugate contains less than 15% Free saccharide, more preferably less than 10% Free saccharide, and even more preferably less than 5% Free saccharide.

Serotype 11A glycoconjugates can also be characterized by their molecular size distribution (K _d ). Gel Permeation Media Chromatography (CL-4B) can be used to determine the relative molecular size distribution of the conjugate as described above.

In a preferred embodiment, at least 30% of the serotype 11A glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85% of the serotype 11A glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 60% of the serotype 11A glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 65% of the serotype 11A glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column.

1.3.8. Glycoconjugates from S. pneumoniae serotype 8

In one embodiment, serotype 8 glycoconjugates are prepared by activating the polysaccharide with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) to form a cyanate ester. The activated polysaccharide can be attached directly or through a spacer (linker) group to the amino group on the carrier protein. For example, the spacer can be a cystamine or a cysteamine yielding a thiolated polysaccharide that can be attached to the carrier via a thioether bond formed after reaction with a maleimide-activated carrier protein (e.g., using GMBS) or a haloacetylated carrier protein (e.g., using iodoacetamide, SIB, SIAB, sulfo-SIAB, SIA, or SBAP). Preferably, the cyanate ester (optionally prepared using CDAP chemistry) is coupled to hexanediamine or adipic acid hydrazide (ADH) and the amino-derivatized saccharide is conjugated to the carrier protein using carbodiimide (e.g., EDAC or EDC) chemistry through the carboxyl group on the protein. carrier. Such conjugates are described, for example, in WO 93/15760, WO 95/08348 and WO 96/129094.

Other suitable methods use carbodiimides, hydrazides, active esters, norborane, p-nitrobenzoic acid, N-hydroxysuccinimide, S-NHS, EDC, TSTU. Many of these are described in International Patent Publication No. WO 98/42721. The conjugation may include a carbonyl linker, which may be formed by the reaction of the free hydroxyl group of the saccharide with CDI (see Bethell et al. (1979) J. Biol. Chern. 254: 2572-2574; Hearn et al. (1981) J. Chromatogr, 218: 509-518) followed by reaction with the protein to form a carbamate bond. This may include reducing the anomeric end to a primary hydroxyl group, optionally protecting/deprotecting the primary hydroxyl group, reacting the primary hydroxyl group with a CDI to form a CDI carbamate intermediate, and reacting a CDI carbamate intermediate with an amino group on a protein.

In preferred embodiments, the serotype 8 glycoconjugates of the invention are prepared using reductive amination. Reductive amination involves two steps, (1) oxidation of the polysaccharide to form aldehyde functional groups from vicinal diols in the individual hexasaccharide unit, (2) reduction of the activated polysaccharide and carrier protein to form a conjugate.

Prior to oxidation, the serotype 8 polysaccharide is optionally hydrolyzed in order to reduce its viscosity. Mechanical or chemical hydrolysis may be used. Chemical hydrolysis can be carried out using acetic acid.

The oxidation step may include reaction with periodate. For the purposes of the present invention, the term "periodate" includes both periodate and periodic acid; the term also includes both metaperiodate (IO ₄ ^- ) and orthoperiodate (IO ₆ ^5- ) and various periodate salts (eg, sodium periodate and potassium periodate). In one embodiment, the capsular polysaccharide serotype 8 from S. pneumoniae is oxidized in the presence of metaperiodate, preferably in the presence of sodium periodate (NaIO ₄ ). In another embodiment, the serotype 8 capsular polysaccharide is oxidized in the presence of orthoperiodate, preferably in the presence of periodic acid.

After the step of oxidizing the polysaccharide, the polysaccharide is said to be activated and hereinafter referred to as "activated polysaccharide". The activated polysaccharide can be purified and lyophilized (freeze-dried).

The activated polysaccharide and carrier protein may be lyophilized (freeze-dried), or independently (lyophilized separately) or together (co-lyophilized). In one embodiment, the activated polysaccharide and carrier protein are lyophilized together. In another embodiment, the activated polysaccharide and carrier protein are lyophilized independently of each other.

In one embodiment, lyophilization occurs in the presence of a non-reducing sugar, possibly non-reducing sugars include sucrose, trehalose, raffinose, stachyose, melecytose, dextran, mannitol, lactitol, and palatinite.

The second step of the conjugation process is the reduction of the activated polysaccharide and carrier protein to form a conjugate (reductive amination), using a reducing agent. Reducing agents that are suitable include cyanoborohydrides such as sodium cyanoborohydride, borane pyridine, or borohydride exchange resin. In one embodiment, the reducing agent is sodium cyanoborohydride.

In one embodiment, the reduction reaction is carried out in an aqueous solvent, in another embodiment, the reaction is carried out in an aprotic solvent. In one embodiment, the reduction reaction is carried out in DMSO (dimethyl sulfoxide) or DMF (dimethylformamide) as a solvent. A DMSO or DMF solvent can be used to reconstitute the activated polysaccharide and carrier protein that have been lyophilized.

In one embodiment, 0.1 to 3.0, 0.15 to 2.0, 0.2 to 1.0, or 0.25 to 0.5 molar equivalents of sodium cyanoborohydride is used in the reduction reaction. In one embodiment, approximately 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1 .3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5 , 2.6, 2.9, or 3.0 molar equivalents of sodium cyanoborohydride are used in the reduction reaction.

In one embodiment, the reducing agent is sodium triacetoxyborohydride. In a further embodiment, 1.0 to 6.0 molar equivalents, 2.0 to 5.0 molar equivalents, or about 3.0 molar equivalents of sodium triacetoxyborohydride are used in the reduction reaction.

At the end of the reduction reaction, unreacted aldehyde groups may remain in the conjugates and may be blocked with a suitable blocking agent. In one embodiment, this blocking agent is sodium borohydride (NaBH ₄ ). In one embodiment, blocking is achieved by mixing the reduction reaction with 0.5 to 5.0 molar equivalents of NaBH ₄ , such as about 1.0, 1.5, 2.0, 2.5, or 3.0 molar equivalents of NaBH ₄ .

After conjugation (reduction reaction and optionally blocking), the glycoconjugates can be purified. Glycoconjugates can be purified using diafiltration and/or ion exchange chromatography and/or gel permeation chromatography. In one embodiment, the glycoconjugates are purified using diafiltration and/or ion exchange chromatography and/or gel permeation chromatography.

In one embodiment, the glycoconjugates are subjected to sterilizing filtration.

In some embodiments, the serotype 8 glycoconjugates of the present invention are conjugated to a carrier protein (eg, CRM ₁₉₇ ) and contain a saccharide having a molecular weight of 10 kDa to 2000 kDa. In other such embodiments, the saccharide has a molecular weight of 50 kDa to 2000 kDa. In further such embodiments, the saccharide has a molecular weight of 50 kDa to 1750 kDa; from 50 kDa to 1500 kDa; from 50 kDa to 1250 kDa; from 50 kDa to 1000 kDa; from 50 kDa to 750 kDa; from 50 kDa to 500 kDa; from 100 kDa to 2000 kDa; from 100 kDa to 1750 kDa; from 100 kDa to 1500 kDa; from 100 kDa to 1250 kDa; from 100 kDa to 1000 kDa; from 100 kDa to 750 kDa; from 100 kDa to 500 kDa; from 200 kDa to 2000 kDa; from 200 kDa to 1750 kDa; from 200 kDa to 1500 kDa; from 200 kDa to 1250 kDa; from 200 kDa to 1000 kDa; from 200 kDa to 750 kDa; or from 200 kDa to 500 kDa; or from 200 kDa to 400 kDa. In one embodiment, said serotype 8 glycoconjugates are prepared using reductive amination.

In some embodiments, the serotype 8 glycoconjugate of the invention has a molecular weight of 50 kDa to 20,000 kDa. In other embodiments, the serotype 8 glycoconjugate has a molecular weight of 50 kDa to 15,000 kDa. In other embodiments, the serotype 8 glycoconjugate has a molecular weight of 500 kDa to 10,000 kDa. In other embodiments, the serotype 8 glycoconjugate has a molecular weight of 200 kDa to 10,000 kDa. In yet other embodiments, the serotype 8 glycoconjugate has a molecular weight of 1000 kDa to 8000 kDa, or 2000 kDa to 8000 kDa.

In further embodiments, the serotype 8 glycoconjugate of the invention has a molecular weight of 200 kDa to 20,000 kDa; from 200 kDa to 15000 kDa; from 200 kDa to 10,000 kDa; from 200 kDa to 7500 kDa; from 200 kDa to 5000 kDa; from 200 kDa to 3000 kDa; from 200 kDa to 1000 kDa; from 500 kDa to 20,000 kDa; from 500 kDa to 15000 kDa; from 500 kDa to 12500 kDa; from 500 kDa to 10,000 kDa; from 500 kDa to 7500 kDa; from 500 kDa to 6000 kDa; from 500 kDa to 5000 kDa; from 500 kDa to 4000 kDa; from 500 kDa to 3000 kDa; from 500 kDa to 2000 kDa; from 500 kDa to 1500 kDa; from 500 kDa to 1000 kDa; from 750 kDa to 20,000 kDa; from 750 kDa to 15000 kDa; from 750 kDa to 12500 kDa; from 750 kDa to 10000 kDa; from 750 kDa to 7500 kDa; from 750 kDa to 6000 kDa; from 750 kDa to 5000 kDa; from 750 kDa to 4000 kDa; from 750 kDa to 3000 kDa; from 750 kDa to 2000 kDa; from 750 kDa to 1500 kDa; from 1000 kDa to 15000 kDa; from 1000 kDa to 12500 kDa; from 1000 kDa to 10000 kDa; from 1000 kDa to 7500 kDa; from 1000 kDa to 6000 kDa; from 1000 kDa to 5000 kDa; from 1000 kDa to 4000 kDa; from 1000 kDa to 2500 kDa; from 2000 kDa to 15000 kDa; from 2000 kDa to 12500 kDa; from 2000 kDa to 10000 kDa; from 2000 kDa to 7500 kDa; from 2000 kDa to 6000 kDa; from 2000 kDa to 5000 kDa; from 2000 kDa to 4000 kDa; or from 2000 kDa to 3000 kDa.

In further embodiments, the serotype 8 glycoconjugate of the invention has a molecular weight of 3,000 kDa to 20,000 kDa; from 3000 kDa to 15000 kDa; from 3000 kDa to 10000 kDa; from 3000 kDa to 7500 kDa; from 3000 kDa to 5000 kDa; from 4000 kDa to 20000 kDa; from 4000 kDa to 15000 kDa; from 4000 kDa to 12500 kDa; from 4000 kDa to 10000 kDa; from 4000 kDa to 7500 kDa; from 4000 kDa to 6000 kDa; or from 4000 kDa to 5000 kDa. In further embodiments, the serotype 8 glycoconjugate of the invention has a molecular weight of 5,000 kDa to 20,000 kDa; from 5000 kDa to 15000 kDa; 5000 kDa to 10000 kDa or 5000 kDa to 7500 kDa. In further embodiments, the serotype 8 glycoconjugate of the invention has a molecular weight of 6000 kDa to 20000 kDa; from 6000 kDa to 15000 kDa; 6000 kDa to 10000 kDa or 6000 kDa to 7500 kDa.

In further embodiments, the serotype 8 glycoconjugate of the invention has a molecular weight of 7,000 kDa to 20,000 kDa; from 7000 kDa to 15000 kDa; 7000 kDa to 10000 kDa or 7000 kDa to 8000 kDa. In further embodiments, the serotype 8 glycoconjugate of the invention has a molecular weight of 8,000 kDa to 20,000 kDa; from 8000 kDa to 15000 kDa; or from 8000 kDa to 10000 kDa.

In one embodiment, said serotype 8 glycoconjugates are prepared using reductive amination.

Another way to characterize the serotype 8 glycoconjugates of the invention is the number of lysine residues in the carrier protein (eg CRM ₁₉₇ ) that become conjugated to the saccharide, which can be characterized as a range of conjugated lysines (degree of conjugation).

Evidence of a lysine modification of the carrier protein, due to covalent bonds with polysaccharides, can be obtained by amino acid analysis using standard methods known to those skilled in the art. In numerous embodiments, the carrier protein is covalently conjugated to the activated polysaccharide via an amine bond to one or more ε-amino groups of lysine residues on the carrier protein. In some such embodiments, the carrier protein contains 2 to 20 lysine residues covalently conjugated to a saccharide. In other such embodiments, the carrier protein contains 4 to 16 or 6 to 14 lysine residues covalently conjugated to a saccharide.

In a preferred embodiment, the degree of conjugation of the serotype 8 glycoconjugate of the invention is 2 to 20, 2 to 15, 2 to 13, 2 to 10, 2 to 8, 2 to 6, 2 to 5, 2 to 4, 3 to 15, 3 to 13, 3 to 10, 3 to 8, 3 to 6, 3 to 5, 3 to 4, 5 to 15, 5 to 10, 8 up to 15, 8 to 12, 10 to 15, or 10 to 12. In one embodiment, the degree of conjugation of the serotype 8 glycoconjugate of the invention is about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, or about 15. In a preferred embodiment, the degree of conjugation of the serotype 8 glycoconjugate of the invention is 4 to 16, or 6 to 14. In some such embodiments, implementation, the carrier protein is CRM ₁₉₇ .

In a preferred embodiment, the carrier protein contains CRM ₁₉₇ which contains 39 lysine residues. In some such embodiments, CRM ₁₉₇ may contain 4 to 16 or 6 to 14 of the 39 lysine residues covalently linked to the saccharide. Another way to express this parameter is that from about 10% to about 41% or from about 15% to about 36% of the CRM ₁₉₇ lysins are covalently linked to the saccharide. In another such embodiment, CRM ₁₉₇ may contain from 2 to 20 of the 39 lysine residues covalently linked to the saccharide. Another way to express this parameter is that from about 5% to about 50% of the CRM _{197 lysins} are covalently linked to the saccharide. In some such embodiments, CRM ₁₉₇ may contain approximately 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 of the 39 lysine residues covalently linked to the saccharide.

The serotype 8 glycoconjugates of the invention can also be characterized by the ratio (w/w) of saccharide to carrier protein. In some embodiments, the ratio of saccharide to carrier protein (w/w) is 0.2 to 4.0 (e.g., about 0.2, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, about 1.8, about 1.9, about 2.0, about 2.1, about 2.2, about 2.3, about 2.4, about 2.5, about 2.6, about 2.7, about 2.8, about 2.9, about 3.0, about 3.1, about 3.2, about 3.3, about 3.4, about 3.5, about 3.6, about 3.7, about 3.8, about 3.9, or about 4.0). In other embodiments, the ratio of saccharide to carrier protein (w/w) is 0.7 to 2.5. In the following embodiments, the ratio of saccharide to carrier protein (w/w) is 0.8 to 1.5 (e.g., about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, or about 1.5). In some such embodiments, the carrier protein is CRM ₁₉₇ . In one embodiment, said serotype 8 glycoconjugates are prepared using reductive amination.

Serotype 8 glycoconjugates and the immunogenic composition of the invention may contain a free saccharide that is not covalently conjugated to the carrier protein, but is nonetheless present in the glycoconjugate composition. The free saccharide may be non-covalently associated with (ie, non-covalently associated with, adsorbed to, or enclosed in or with) the glycoconjugate.

In some embodiments, the serotype 8 glycoconjugates of the invention contain less than about 50% Free saccharide, less than about 45% Free saccharide, less than about 40% Free saccharide, less than about 35% Free saccharide, less than about 30% Free saccharide, less than about 25% Free saccharide, less than about 20% Free saccharide, less than about 15% Free saccharide, less than about 10% Free saccharide, or less than about 5% Free saccharide relative to total serotype 8 saccharide. Preferably, the serotype 8 glycoconjugate contains less than 15% Free saccharide, more preferably less than 10% Free saccharide, and even more preferably less than 5% Free saccharide.

Serotype 8 glycoconjugates can also be characterized by their molecular size distribution (K _d ). Gel Permeation Media Chromatography (CL-4B) can be used to determine the relative molecular size distribution of the conjugate. Gel permeation chromatography (SEC) is used in columns fed by gravity to the molecular size distribution profile of the conjugates. Large molecules excluded from pores elute more rapidly in media than small molecules. Fraction collectors are used to collect column eluate. Fractions are examined colorimetrically using saccharide analysis. To determine K _d , the columns are calibrated to establish the fraction in which the molecules are completely excluded (V ₀ ), (K _d =0), and the fraction that represents the maximum retention (V _i ), (K _d =1). The fraction in which the specified characteristic of the sample (V _e ) is achieved is related to K _d by the expression, K _d =(V _e -V ₀ )/(V _i -V ₀ ).

In a preferred embodiment, at least 40% of the serotype 8 glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85% of the serotype 8 glycoconjugates of the invention have a K _d less than or equal to 0.3 in column CL-4B. In a preferred embodiment, at least 60% of the serotype 8 glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, at least 70% of the serotype 8 glycoconjugates of the invention have a K _d less than or equal to 0.3 in a CL-4B column.

In a preferred embodiment, 40% to 90% of serotype 8 glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 50% to 90% of the serotype 8 glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column. In a preferred embodiment, 65% to 80% of the serotype 8 glycoconjugates have a K _d less than or equal to 0.3 in a CL-4B column.

1.4 Combinations of glycoconjugates according to the invention

In one embodiment, the immunogenic composition according to the invention contains any of the glycoconjugates disclosed herein.

In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate selected from the group consisting of a glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above), a glycoconjugate from S. pneumoniae serotype 22F ( such as glycoconjugates from section 1.3.2 above), glycoconjugate from S. pneumoniae serotype 33F (such as glycoconjugates from section 1.3.3 above), glycoconjugate from S. pneumoniae serotype 12F (such as glycoconjugates from section 1.3.5 above), glycoconjugate from S. pneumoniae serotype 10A (such as the glycoconjugates from section 1.3.6 above), a glycoconjugate from S. pneumoniae serotype 11A (such as the glycoconjugates from section 1.3.7 above), and a glycoconjugate from S. pneumoniae serotype 8 (such as the glycoconjugates from section 1.3.8 above).

In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate from S. pneumoniae serotype 15B, such as the glycoconjugate from section 1.3.4 above. In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate from S. pneumoniae serotype 22F, such as those disclosed in section 1.3.2 above. In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate from S. pneumoniae serotype 33F, such as those disclosed in section 1.3.3 above. In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate from S. pneumoniae serotype 12F, such as those disclosed in section 1.3.5 above. In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate from S. pneumoniae serotype 10A, such as those disclosed in section 1.3.6 above. In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate from S. pneumoniae serotype 11A, such as those disclosed in section 1.3.7 above. In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate from S. pneumoniae serotype a 8, such as those disclosed in section 1.3.8 above.

In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate of each of two S. pneumoniae serotypes selected from the group consisting of: 15B and 22F, 15B and 33F, 15B and 12F, 15B and 10A, 15B and 11A , 15V&8, 22F&33F, 22F&12F, 22F&10A, 22F&11A, 22F&8, 33F&12F, 33F&10A, 33F&11A, 33F&8, 12F&10A, 12F&11A, 12F and 8, 10A and 11A, 10A and 8, and 11A and 8.

In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate of each of the following three S. pneumoniae serotypes:

15B and 22F and 33F,

15B & 22F & 12F,

15B & 22F & 10A,

15B & 22F & 11A,

15B and 22F and 8,

15B & 33F & 12F,

15B & 33F & 10A,

15V and 33F and 11A,

15B and 33F and 8,

15V & 12F & 10A,

15B & 12F & 11A,

15B and 12F and 8,

15V and 10A and 11A,

15V and 10A and 8,

15V and 11A and 8,

22F, 33F, 12F,

22F and 33F and 10A,

22F and 33F and 11A,

22F and 33F and 8,

22F and 12F and 10A,

22F and 12F and 11A,

22F and 12F and 8,

22F and 10A and 11A,

22F and 10A and 8,

22F and 11A and 8,

33F and 12F and 10A,

33F&12F&11A,

33F and 12F and 8,

33F and 10A and 11A,

33F and 10A and 8,

33F and 11A and 8,

12F & 10A & 11A,

12F and 10A and 8,

12F and 11A and 8, or

10A and 11A and 8.

In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate of each of the four following S. pneumoniae serotypes:

15V & 22F & 33F & 12F,

15V & 22F & 33F & 10A,

15B, 22F, 33F, 11A,

15B and 22F and 33F and 8,

15B and 22F and 12A and 10A,

15V & 22F & 12F & 11A,

15B, 22F, 12F, 8,

15V & 22F & 10A & 11A,

15B & 22F & 10A & 8,

15V & 22F & 11A & 8,

15V & 33F & 12F & 10A,

15V & 33F & 12F & 11A,

15V & 33F & 12F & 8,

15V and 33F and 10A and 11A,

15V & 33F & 10A & 8,

15V and 33F and 11A and 8,

15V & 12F & 10A & 11A,

15V & 12F & 10A & 8,

15V & 12F & 11A & 8,

15V and 10A and 11A and 8,

22F, 33F, 12F, 10A,

22F and 33F and 12F and 11A,

22F, 33F, 12F, 8,

22F and 33F and 10A and 11A,

22F and 33F and 10A and 8,

22F and 33F and 11A and 8,

22F and 12F and 10A and 11A,

22F & 12F & 10A & 8,

22F and 12F and 11A and 8,

22F and 10A and 11A and 8,

33F, 12F, 10A, 11A,

33F, 12F, 10A, 8,

33F and 12F and 11A and 8,

33F and 10A and 11A and 8 or

12F and 10A and 11A and 8.

In one embodiment, the immunogenic composition according to the invention contains at least one glycoconjugate of each of the following five S. pneumoniae serotypes:

15V & 22F & 33F & 12F & 10A,

15B, 22F, 33F, 12F, 11A,

15V, 22F, 33F, 12F, 8,

15V & 22F & 33F & 10A & 11A,

15V & 22F & 33F & 10A & 8,

15V & 22F & 33F & 11A & 8,

15V & 22F & 12F & 10A & 11A,

15V & 22F & 12F & 10A & 8,

15V & 22F & 12F & 11A & 8,

15B and 22F and 10A and 11A and 8,

15B & 33F & 12F & 10A & 11A,

15B & 33F & 12F & 10A & 8,

15V & 33F & 12F & 11A & 8,

15V & 33F & 10A & 11A & 8,

15V & 12F & 10A & 11A & 8,

22F, 33F, 12F, 10A, 11A,

22F, 33F, 12F, 10A, 8,

22F & 33F & 12F & 11A & 8,

22F, 33F, 10A, 11A, 8,

22F and 12F and 10A and 11A and 8 or

33F and 12F and 10A and 11A and 8.

In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate of each of the six following S. pneumoniae serotypes:

15V, 22F, 33F, 12F, 10A, 11A,

15V, 22F, 33F, 12F, 10A, 8,

15B, 22F, 33F, 12F, 11A, 8,

15V, 22F, 33F, 10A, 11A, 8,

15V, 22F, 12F, 10A, 11A, 8,

15V, 33F, 12F, 10A, 11A, 8 or

22F and 33F and 12F and 10A and 11A and 8.

In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate of each of the following seven S. pneumoniae serotypes: 15B and 22F and 33F and 12F and 10A and 11A and 8.

In one embodiment, glycoconjugates from S. pneumoniae serotypes 15B, 22F, 33F, 12F, 10A, 11A and/or 8 of any of the immunogenic compositions defined in this section are as disclosed in sections 1.3.2 to 1.3.8 above.

In one embodiment, any of the immunogenic compositions above further comprises glycoconjugates from S. pneumoniae serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F (such as the glycoconjugates from section 1.3.1 above).

In one embodiment, any of the immunogenic compositions above further comprises glycoconjugates from S. pneumoniae serotypes 1, 5, and 7F (such as the glycoconjugates from section 1.3.1 above).

In one embodiment, any of the immunogenic compositions above further comprises glycoconjugates from S. pneumoniae serotypes 6A and 19A (such as the glycoconjugates from section 1.3.1 above).

In one embodiment, any of the immunogenic compositions above further comprises glycoconjugates from S. pneumoniae serotype 3 (such as the glycoconjugates from section 1.3.1 above).

Preferably, all glycoconjugates from the above immunogenic composition are individually conjugated to a carrier protein.

In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotype 22F are conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotype 33F are conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotype 15B are conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotype 12F are conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotype 10A are conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotype 11A are conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotype 8 are conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotypes 4, 6B, 9V, 14, 18C, 19F and 23F are CRM ₁₉₇ conjugated. In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotypes 1, 5 and 7F are CRM ₁₉₇ conjugated. In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotypes 6A and 19A are CRM ₁₉₇ conjugated. In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotype 3 are conjugated to CRM ₁₉₇ .

In one embodiment, the glycoconjugates of any of the above immunogenic compositions are all individually conjugated to CRM ₁₉₇ .

In one embodiment, glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, 14 and/or 23F of any of the above immunogenic compositions are individually conjugated to PD.

In one embodiment, the S. pneumoniae serotype 18C glycoconjugate of any of the above immunogenic compositions is conjugated to TT.

In one embodiment, the S. pneumoniae serotype 19F glycoconjugate of any of the above immunogenic compositions is conjugated to DT.

In one embodiment, glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, 14 and/or 23F of any of the above immunogenic compositions are individually conjugated to PD, glycoconjugate from S. pneumoniae serotype 18C conjugated to TT, and the glycoconjugate from S. pneumoniae serotype 19F is conjugated to DT.

In one embodiment, the above immunogenic composition contains from 8 to 20 different serotypes from S. pneumoniae. In one embodiment, the above immunogenic composition contains glycoconjugates from 12, 13, 14, 15, 16, 17, 18, 19, or 20 different serotypes. In one embodiment, the above immunogenic composition contains glycoconjugates from 16 or 20 different serotypes.

In one embodiment, the above immunogenic composition is 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20-valent pneumococcal conjugate compositions. In one embodiment, the above immunogenic composition is a 14, 15, 16, 17, 18 or 19 valent pneumococcal conjugate composition. In one embodiment, the above immunogenic composition is a 16-valent pneumococcal conjugate composition. In one embodiment, the above immunogenic composition is a 19-valent pneumococcal conjugate composition.

1. In one embodiment, the immunogenic composition of the invention comprises at least one glycoconjugate from S. pneumoniae serotype 15B, such as the glycoconjugates of section 1.3.4 above.

2. In another embodiment, the immunogenic composition according to the invention contains, in addition to paragraph 1 above, at least one glycoconjugate from S. pneumoniae serotype 22F, such as those disclosed in section 1.3.2 above.

3. In another embodiment, the immunogenic composition according to the invention contains, in addition to paragraph 1 or 2 above, at least one glycoconjugate from S. pneumoniae serotype 33F, such as those disclosed in section 1.3.3 above.

4. In another embodiment, the immunogenic composition according to the invention contains, in addition to paragraph 1, 2 or 3 above, at least one glycoconjugate from S. pneumoniae serotype 12F, such as those disclosed in section 1.3.5 above.

5. In another embodiment, the immunogenic composition according to the invention contains, in addition to paragraph 1,2,3 or 4 above, at least one glycoconjugate from S. pneumoniae serotype 10A, such as those disclosed in section 1.3.6 above.

6. In another embodiment, the immunogenic composition according to the invention contains, in addition to paragraph 1, 2, 3, 4 or 5 above, at least one glycoconjugate from S. pneumoniae serotype 11A, such as those disclosed in section 1.3 .7 above.

7. In another embodiment, the immunogenic composition according to the invention contains, in addition to paragraph 1, 2, 3, 4, 5 or 6 above, at least one glycoconjugate from S. pneumoniae serotype 8, such as those disclosed in section 1.3.8 above.

8. In another embodiment, the immunogenic composition according to the invention contains, in addition to paragraph 1, 2, 3, 4, 5, 6 or 7 above, glycoconjugates from S. pneumoniae serotypes 4, 6B, 9V, 14, 18C, 19F and 23F, such as the glycoconjugates from section 1.3.1 above.

9. In another embodiment, the immunogenic composition of the invention comprises, in addition to items 1, 2, 3, 4, 5, 6, 7, or 8 above, glycoconjugates from S. pneumoniae serotypes 1, 5, and 7F, such as glycoconjugates from section 1.3.1 above.

10. In another embodiment, the immunogenic composition of the invention comprises, in addition to items 1, 2, 3, 4, 5, 6, 7, 8, or 9 above, glycoconjugates from S. pneumoniae serotypes 6A and 19A, such as glycoconjugates from section 1.3.1 above.

11. In another embodiment, the immunogenic composition of the invention comprises, in addition to items 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 above, glycoconjugates from S. pneumoniae serotype 3, such as glycoconjugates from section 1.3.1 above.

In one embodiment, the immunogenic composition of the invention comprises glycoconjugates from S. pneumoniae serotypes 1,3,4, 5, 6A, 6B, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F.

In one embodiment, the immunogenic composition of the invention comprises glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6A, 6B, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F.

In one embodiment, the immunogenic composition of the invention comprises conjugated saccharides from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F , 22F, 23F and 33F.

In one embodiment, the immunogenic composition of the invention comprises conjugated saccharides from S. pneumoniae serotypes 1, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F , 23F and 33F.

In one embodiment, the glycoconjugates of the immunogenic composition of the invention comprise glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F. In one embodiment, the glycoconjugates of the immunogenic composition of the invention comprise glycoconjugates of serotypes 1, 4, 5, 6A, 6B, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F. In one embodiment, the glycoconjugates of the immunogenic composition of the invention comprise glycoconjugates of serotypes 1, 3, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F and 33F. In one embodiment, the glycoconjugates of the immunogenic composition of the invention comprise glycoconjugates from 1, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F and 33F .

Preferably, all glycoconjugates of an immunogenic composition according to the invention (eg, any of paragraphs 1-11 above) are individually conjugated to a carrier protein.

In one embodiment, glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, 14 and/or 23F of any of items 8-11 above are individually conjugated to PD.

In one embodiment, the S. Pneumoniae serotype 18C glycoconjugate of any of items 8-11 above is conjugated to TT.

In one embodiment, the S. pneumoniae serotype 19F glycoconjugate of any of items 8-11 above is conjugated to DT.

In one embodiment of any of 8-11 above, the glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, 14, and/or 23F are individually conjugated to PD, the glycoconjugate from S . pneumoniae serotype 18C is conjugated to TT, and the glycoconjugate from S. pneumoniae serotype 19F is conjugated to DT.

In one embodiment of any of items 1-11 above, the glycoconjugate from S. pneumoniae serotype 22F is conjugated to CRM ₁₉₇ . In one embodiment of any of items 2-11 above, the glycoconjugate from S. pneumoniae serotype 33F is conjugated to CRM ₁₉₇ . In one embodiment of any of items 3-11 above, the glycoconjugate from S. pneumoniae serotype 15B is conjugated to CRM ₁₉₇ . In one embodiment, according to any of items 4-11 above, the glycoconjugate from S. pneumoniae serotype 12F is conjugated to CRM ₁₉₇ . In one embodiment of any of items 5-11 above, the glycoconjugate from S. pneumoniae serotype 10A is conjugated to CRM ₁₉₇ . In one embodiment, according to any of paragraphs 6-11 above, the glycoconjugate from S. pneumoniae serotype 11A is conjugated to CRM ₁₉₇ . In one embodiment, according to any of paragraphs 7-11 above, the glycoconjugate from S. pneumoniae serotype 8 conjugated with CRM ₁₉₇ . In one embodiment, according to any of paragraphs 8-11 above, glycoconjugates from S. pneumoniae serotypes 4, 6B, 9V, 14, 18C, 19F and 23F are CRM ₁₉₇ conjugated. In one embodiment, according to any of paragraphs 9-11 above, glycoconjugates from S. pneumoniae serotypes 1, 5 and 7F are CRM ₁₉₇ conjugated. In one embodiment of any of 10 or 11 above, the glycoconjugates from S. pneumoniae serotypes 6A and 19A are CRM ₁₉₇ conjugated. In one embodiment of item 11 above, the glycoconjugate from S. pneumoniae serotype 3 is conjugated to CRM ₁₉₇ .

In one embodiment, the glycoconjugates of the immunogenic composition of items 1-11 above are individually conjugated to CRM ₁₉₇ .

In one embodiment, the immunogenic composition according to the invention contains from 12 to 20 different serotypes of S. pneumoniae. In one embodiment, the immunogenic composition of the invention contains glycoconjugates from 12, 13, 14, 15, 16, 17, 18, 19, or 20 different serotypes. In one embodiment, the immunogenic composition of the invention contains glycoconjugates from 16 or 20 different serotypes.

In one embodiment, the immunogenic composition of items 1-11 above is an 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20-valent pneumococcal conjugate composition. In one embodiment, the immunogenic composition of items 1-11 above is a 15, 16, 17, 18 or 19 valent pneumococcal conjugate composition. In one embodiment, the immunogenic composition of items 1-11 above is a 16-valent pneumococcal conjugate composition. In one embodiment, the immunogenic composition of items 1-11 above is a 19-valent pneumococcal conjugate composition.

After the capsular polysaccharide has been conjugated to the carrier protein, the glycoconjugates are purified (enriched relative to the amount of the polysaccharide-protein conjugate) using various methods. These methods include concentration/diafiltration, precipitation/elution, column chromatography, and depth filtration (see, for example, US Patent Application Publication No. 2007/0184072 or WO 2008/079653). After the individual glycoconjugates are purified, they are mixed to formulate an immunogenic composition according to the present invention.

1.5 Additional combinations of glycoconjugates according to the invention

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate from S. pneumoniae serotype 9V.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate of each of two S. pneumoniae serotypes selected from the group consisting of: 9V and 4, 9V and 6B, 9V and 14, 9V and 18C, 9V and 19F, 9V and 23F.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate of each of the seven following S. pneumoniae serotypes: 9V, 4, 6B, 14, 18C, 19F, and 23F.

In one embodiment, any immunogenic composition as defined in Section 1.4 above further comprises at least one glycoconjugate of each of the eight following S. pneumoniae serotypes:

9V&1&4&6V&14&18C&19F&23F,

9V and 4 and 5 and 6V and 14 and 18C and 19F and 23F, or

9V and 4 and 6B and 7F and 14 and 18C and 19F and 23F.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate of each of the following ten S. pneumoniae serotypes: 9V, 1, 5, 4, 6B, 7F, 14, 18C, 19F and 23F.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate of each of the eleven following S. pneumoniae serotypes:

9V and 1 and 4 and 5 and 6A and 6B and 7F and 14 and 18C and 19F and 23F or

9V and 1 and 4 and 5 and 6B and 7F and 14 and 18C and 19A and 19F and 23F.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate of each of the following twelve S. pneumoniae serotypes: 9V, 1, 4, 5, 6A, 6B, 7F, 14, 18C, 19A, 19F and 23F.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate of each of the thirteen following S. pneumoniae serotypes: 9V, 1, 3, 4, 5, 6A, 6B, 7F, 14, 18C, 19A, 19F and 23F.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one S. pneumoniae serotype 2 glycoconjugate.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate from S. pneumoniae serotype 17F.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate from S. pneumoniae serotype 20.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate from S. pneumoniae serotype 15C.

In one embodiment, any immunogenic composition as defined in section 1.4 above further comprises at least one glycoconjugate from S. pneumoniae serotype 9N.

Preferably, all glycoconjugates of the above immunogenic composition are individually conjugated to a carrier protein.

In one embodiment, any of the above immunogenic compositions, the glycoconjugate from S. pneumoniae serotype 9V is conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotypes 4, 6B, 14, 18C, 19F, and 23F are CRM ₁₉₇ conjugated. In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotypes 1, 5 and 7F are CRM ₁₉₇ conjugated. In one embodiment, any of the above immunogenic compositions, glycoconjugates from S. pneumoniae serotypes 6A and 19A are CRM ₁₉₇ conjugated. In one embodiment, any of the above immunogenic compositions, the glycoconjugate from S. pneumoniae serotype 3 is conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, the glycoconjugate from S. pneumoniae serotype 2 is conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, the glycoconjugate from S. pneumoniae serotype 17F is conjugated to CRM ₁₉₇ . In one embodiment of any of the above immunogenic compositions, the glycoconjugate from S. pneumoniae serotype 20 is conjugated to CRM ₁₉₇ . In one embodiment of any of the above immunogenic compositions, the glycoconjugate from S. Pneumoniae serotype 15C is conjugated to CRM ₁₉₇ . In one embodiment, any of the above immunogenic compositions, the glycoconjugate from S. pneumoniae serotype 9N is conjugated to CRM ₁₉₇ . In one embodiment, the glycoconjugates of the above immunogenic composition are all individually conjugated to CRM ₁₉₇ .

In another embodiment, the S. pneumoniae serotype 9V glycoconjugate of any of the above immunogenic compositions is separately conjugated to cPD.

In one embodiment, glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, 14 and/or 23F of any of the above immunogenic compositions are individually conjugated to PD.

In one embodiment, the S. pneumoniae serotype 18C glycoconjugate of any of the above immunogenic compositions is conjugated to TT.

In one embodiment, the S. pneumoniae serotype 19F glycoconjugate of any of the above immunogenic compositions is conjugated to DT.

In one embodiment, glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, 14 and/or 23F of any of the above immunogenic compositions are individually conjugated to PD, glycoconjugate from S. pneumoniae serotype 18C is conjugated to TT, and a glycoconjugate from S. pneumoniae serotype 19F is conjugated to DT.

In one embodiment, the above immunogenic composition contains from 7 to 25 different serotypes of S. pneumoniae. In one embodiment, the above immunogenic composition contains glycoconjugates from 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 different serotypes . In one embodiment, the above immunogenic composition contains glycoconjugates from 16 or 20 different serotypes.

In one embodiment, the above immunogenic composition is 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20-valent pneumococcal conjugate compositions. In one embodiment, the above immunogenic composition is a 14, 15, 16, 17, 18 or 19 valent pneumococcal conjugate composition. In one embodiment, the above immunogenic composition is a 16-valent pneumococcal conjugate composition. In one embodiment, the above immunogenic composition is a 19-valent pneumococcal conjugate composition. In one embodiment, the above immunogenic composition is a 20-valent pneumococcal conjugate composition. After the capsular polysaccharide has been conjugated to the carrier protein, the glycoconjugates are purified (enriched relative to the amount of the polysaccharide-protein conjugate) using various methods. These methods include concentration/diafiltration, precipitation/elution, column chromatography, and depth filtration (see, for example, US Patent Application Publication No. 2007/0184072 or WO 2008/079653. After the individual glycoconjugates are purified, they are mixed to to formulate an immunogenic composition according to the present invention.

1.6 Specific combinations of glycoconjugates according to the invention

In one embodiment, any immunogenic composition as defined in section 1.4 or 1.5 above does not contain a capsular saccharide from S. pneumoniae serotype 9N.

In one embodiment, any immunogenic composition as defined in section 1.4 or 1.5 above does not contain a capsular saccharide from S. pneumoniae serotype 9A.

In one embodiment, any immunogenic composition as defined in section 1.4 or 1.5 above does not contain a capsular saccharide from S. pneumoniae serotype 9L.

In one embodiment, any immunogenic composition as defined in section 1.4 or 1.5 above does not contain a capsular saccharide from S. pneumoniae serotypes 9N and 9A.

In one embodiment, any immunogenic composition as defined in section 1.4 or 1.5 above does not contain a capsular saccharide from S. pneumoniae serotypes 9N and 9L.

In one embodiment, any immunogenic composition as defined in section 1.4 or 1.5 above does not contain a capsular saccharide from S. pneumoniae serotypes 9A and 9L.

In one embodiment, any immunogenic composition as defined in section 1.4 or 1.5 above does not contain a capsular saccharide from S. pneumoniae serotypes 9N, 9A and 9L.

2 Dosage of the immunogenic composition

The amount of glycoconjugate(s) in each dose is chosen as the amount that induces an immune protective response without significant, adverse side effects in typical vaccines. This amount will vary depending on which specific immunogen is being used and how it is presented.

2.1 Amount of glycoconjugate

The amount of a particular glycoconjugate in an immunogenic composition can be calculated based on the total polysaccharide for that conjugate (conjugated and unconjugated). For example, a glycoconjugate with 20% free polysaccharide will have approximately 80 μg of conjugated polysaccharide and approximately 20 μg of unconjugated polysaccharide in a 100 μg dose of polysaccharide. The amount of glycoconjugate may vary depending on the pneumococcal serotype. The saccharide concentration can be determined using an uronic acid assay.

The "immunogenic amount" of the various polysaccharide components in the immunogenic composition may vary and each may contain about 1 µg, about 2 µg, about 3 µg, about 4 µg, about 5 µg, about 6 µg, about 7 µg, about 8 µg, about 9 micrograms, approximately 10 micrograms, approximately 15 micrograms, approximately 20 micrograms, approximately 30 micrograms, approximately 40 micrograms, approximately 50 micrograms, approximately 60 micrograms, approximately 70 micrograms, approximately 80 micrograms, approximately 90 micrograms, or approximately 100 micrograms of any specific polysaccharide antigen.

Typically, each dose will contain 0.1 µg to 100 µg of the polysaccharide for a given serotype, specifically 0.5 µg to 20 µg, more specifically 1.0 µg to 10 µg, and even more specifically 2.0 µg up to 5.0 mcg. Any integer integer within any of the ranges above is contemplated as an embodiment of the invention.

In one embodiment, each dose will contain about 1.0 µg, about 1.2 µg, about 1.4 µg, about 1.6 µg, about 1.8 µg, about 2.0 µg, about 2.2 µg, about 2.4 micrograms, approximately 2.6 micrograms, approximately 2.8 micrograms, approximately 3.0 micrograms, approximately 3.2 kg, approximately 3.4 micrograms, approximately 3.6 micrograms, approximately 3.8 micrograms, approximately 4, 0 mcg, approximately 4.2 mcg, approximately 4.4 mcg, approximately 4.6 mcg, approximately 4.8 mcg, approximately 5.0 mcg, approximately 5.2 mcg, approximately 5.4 mcg, approximately 5.6 mcg , approximately 5.8 μg or approximately 6.0 μg of the polysaccharide for each particular glycoconjugate.

In one embodiment, each dose will contain about 1.1 micrograms, about 1.2 micrograms, about 1.3 micrograms, about 1.4 micrograms, about 1.5 micrograms, about 1.6 micrograms, about 1.7 micrograms, about 1.8 micrograms, approximately 1.9 micrograms, approximately 2.0 micrograms, approximately 2.1 micrograms, approximately 2.2 micrograms, approximately 2.3 micrograms, approximately 2.4 micrograms, approximately 2.5 micrograms, approximately 2, 6 μg, approximately 2.7 μg, approximately 2.8 μg, approximately 2.9 μg, or approximately 3.0 μg polysaccharide for glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 7F, 8, 9V , 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F and/or 33F.

In one embodiment, each dose will contain about 1.1 µg, about 1.2 µg, about 1.3 µg, about 1.4 µg, about 1.5 µg, about 1.6 µg, about 1.7 μg, approximately 1.8 μg, approximately 1.9 μg, approximately 2.0 μg, approximately 2.1 μg, approximately 2.2 μg, approximately 2.3 μg, approximately 2.4 μg, approximately 2.5 μg, about 2.6 µg, about 2.7 µg, about 2.8 µg, about 2.9 µg, or about 3.0 µg polysaccharide for glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6A, 7F, 8, 9V, 10A, 11A, 12F, 14, 15V, 18C, 19A, 19F, 22F, 23F and/or 33F.

In one embodiment, each dose will contain about 2.0 µg, about 2.2 µg, about 2.4 µg, about 2.6 µg, about 2.8 µg, about 3.0 µg, about 3.2 µg , approximately 3.4 μg, approximately 3.6 μg, approximately 3.8 μg, approximately 4.0 μg, approximately 4.2 μg, approximately 4.4 μg, approximately 4.6 μg, approximately 4.8 μg, approximately 5.0 μg, approximately 5.2 μg, approximately 5.4 μg, approximately 5.6 μg, approximately 5.8 μg, or approximately 6.0 μg polysaccharide for glycoconjugates from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain from about 1.5 µg to about 3.0 µg of polysaccharide for each glycoconjugate from S. pneumoniae serotype 1, 3, 4, 5, 6A, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F, and about 3.0 µg to about 6.0 µg of the polysaccharide for the glycoconjugate from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain from about 2.0 µg to about 2.5 µg of polysaccharide for each glycoconjugate from S. pneumoniae serotype 1, 3, 4, 5, 6A, 7F, 8, 9V, 10A, 11 A .

In one embodiment, each dose will contain approximately 2.2 μg of polysaccharide for each glycoconjugate from S. pneumoniae serotype 1, 3, 4, 5, 6A, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C , 19A, 19F, 22F, 23F, and 33F, and approximately 4.4 μg of polysaccharide for glycoconjugate from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain from about 1.5 µg to about 3.0 µg of polysaccharide for each S. pneumoniae serotype 1, 3, 4, 5, 6A, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F, and about 3 µg to about 6 µg of polysaccharide for glycoconjugates from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain from about 2.0 µg to about 2.5 µg of polysaccharide for each S. pneumoniae serotype 1, 3, 4, 5, 6A, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F, and about 4.0 µg to about 4.8 µg of the polysaccharide for the glycoconjugate from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain approximately 2.2 μg of the polysaccharide of each glycoconjugate from S. pneumoniae serotype 1, 3, 4, 5, 6A, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F and 33F, and approximately 4.4 μg polysaccharide for glycoconjugate from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain from about 1.5 µg to about 3.0 µg of polysaccharide for each S. pneumoniae serotype 1, 4, 5, 6A, 7F, 8, 9V, 10A, 11A, 12F glycoconjugate. , 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F, and about 3.0 µg to about 6.0 µg of the polysaccharide for the glycoconjugate from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain from about 2.0 µg to about 2.5 µg of polysaccharide for each glycoconjugate from S. pneumoniae serotype 1, 4, 5, 6A, 7F, 8, 9V, 10A, 11 A, 12F , 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F, and about 4.0 µg to about 4.8 µg of the polysaccharide for the glycoconjugate from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain approximately 2.2 μg of the polysaccharide of each glycoconjugate from S. pneumoniae serotype 1, 4, 5, 6A, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F and 33F, and approximately 4.4 μg polysaccharide for glycoconjugate from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain from about 1.5 µg to about 3.0 µg of polysaccharide for each glycoconjugate from S. pneumoniae serotype 1, 4, 5, 6A, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F, and about 3.0 µg to about 6.0 µg of the polysaccharide for the glycoconjugate from S. pneumoniae serotype 6B.

In one embodiment, each dose will contain from about 2.0 µg to about 2.5 µg of polysaccharide for each S. pneumoniae serotype 1, 4, 5, 6A, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F, and about 4.0 µg to about 4.8 µg polysaccharide for the S. pneumoniae serotype 6B glycoconjugate. In one embodiment, each dose will contain approximately 2.2 μg of the polysaccharide of each glycoconjugate from S. pneumoniae serotypes 1,4,5, 6A, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F, and approximately 4.4 μg polysaccharide for glycoconjugate from S. pneumoniae serotype 6B.

2.2 Media quantity

Typically, each dose will contain 10 µg to 150 µg of carrier protein, specifically 15 µg to 100 µg of carrier protein, more specifically 25 µg to 75 µg of carrier protein, and even more specifically 40 µg to 60 µg carrier protein. In one embodiment, said carrier protein is CRM ₁₉₇ .

In one embodiment, each dose will contain about 25 micrograms, about 26 micrograms, about 27 micrograms, about 28 micrograms, about 29 micrograms, about 30 micrograms, about 31 micrograms, about 32 micrograms, about 33 micrograms, about 34 micrograms, about 35 micrograms, approximately 36 micrograms, approximately 37 micrograms, approximately 38 micrograms, approximately 39 micrograms, approximately 40 micrograms, approximately 41 micrograms, approximately 42 micrograms, approximately 43 micrograms, approximately 44 micrograms, approximately 45 micrograms, approximately 46 micrograms, approximately 47 micrograms , approximately 48 micrograms, approximately 49 micrograms, approximately 50 micrograms, approximately 51 micrograms, approximately 52 micrograms, approximately 53 micrograms, approximately 54 micrograms, approximately 55 micrograms, approximately 56 micrograms, approximately 57 micrograms, approximately 58 micrograms, approximately 59 micrograms, approximately 60 micrograms, approximately 61 micrograms, approximately 62 micrograms, approximately 63 micrograms, approximately 64 micrograms, approximately 65 micrograms g, about 66 µg, about 67 µg, about 68 µg, about 69 µg, about 70 µg, about 71 µg, about 72 µg, about 73 µg, about 74 µg, or about 75 µg carrier protein. In one embodiment, said carrier protein is CRM ₁₉₇ .

3 Additional antigens

The immunogenic composition according to the invention contains S. pneumoniae-conjugated saccharide antigens (glycoconjugates). They may also additionally include antigens from other pathogens, in particular bacteria and/or viruses. Preferred additional antigens are selected from: diphtheria toxoid (D), tetanus toxoid (T), pertussis antigen (P), which is generally acellular (Pa), hepatitis B virus (HBV) surface antigen (HBsAg), hepatitis B virus antigen A (HAV), Haemophilus influenzae type b (Hib) conjugated capsular saccharide, inactivated polio vaccine (IPV).

In one embodiment, the immunogenic composition according to the invention contains D-T-Pa. In one embodiment, the immunogenic composition of the invention comprises D-T-Pa-Hib, D-T-Pa-IPV, or D-T-Pa-HBsAg. In one embodiment, the immunogenic composition of the invention comprises D-T-Pa-HBsAg-IPV or D-T-Pa-HBsAg-Hib. In one embodiment, the immunogenic composition of the invention comprises D-T-Pa-HBsAg-IPV-Hib.

Pertussis antigens: Bordetella pertuss causes whooping cough. Pertussis antigens in vaccines are either cellular (whole cells, as inactivated B. pertussis cells) or acellular. The production of pertussis cellular antigens is well documented (for example, it can be obtained by thermal inactivation of phase I culture of B. pertussis). Preferably, however, the invention uses cell-free antigens. When cell-free antigens are used, it is preferred to use one, two, or (preferably) three of the following antigens: (1) detoxified pertussis toxin (pertussis toxoid, or PT); (2) filamentous haemagglutinin (FHA); (3) pertactin (also known as 69 kiloDalton outer membrane protein). FHA and pertactin may be treated with formaldehyde prior to use in accordance with the present invention. RT is preferably detoxified by treatment with formaldehyde and/or glutaraldehyde. Cell-free pertussis antigens are preferably adsorbed to one or more aluminum salt adjuvants. Alternatively, they may be added in the non-adsorbed state. When pertactin is added, it is preferably always adsorbed onto the aluminum hydroxide adjuvant. PT and FHA can be adsorbed on an aluminum hydroxide or aluminum phosphate adjuvant. Adsorption of all of PT, FHA and pertactin on aluminum hydroxide is most preferred.

Inactivated polio vaccine: Poliovirus causes poliomyelitis. Instead of using an oral poliovirus vaccine, preferred embodiments of the invention use IPV. Prior to administration to patients, polioviruses must be inactivated, and this can be achieved by treatment with formaldehyde. Poliomyelitis can be caused by one of three types of poliovirus. These three types are similar and cause the same symptoms, but they are antigenically different and infection with one type does not protect against infection with the others. Therefore, it is preferred to use three poliovirus antigens in the invention: type 1 poliovirus (eg Mahoney strain), type 2 poliovirus (eg MEF-1 strain), and type 3 poliovirus (eg Saukett strain). The viruses are preferably grown, purified and inactivated individually, and then combined to form a bulk trivalent mixture for use in the present invention.

Diphtheria toxoid: Corynebacterium diphtheriae causes diphtheria. Diphtheria toxin can be treated (eg, using formalin or formaldehyde) to remove toxicity while retaining the ability to induce specific anti-toxin antibodies after injection. These diphtheria toxoids are used in the diphtheria vaccine. Preferred diphtheria toxoids are those obtained by treatment with formaldehyde. Diphtheria toxoid can be obtained by growing C. diphthehae in growth medium, followed by formaldehyde treatment, ultrafiltration and precipitation. The toxoid material can then be processed according to a method including sterile filtration and/or dialysis. The diphtheria toxoid is preferably adsorbed on an aluminum hydroxide adjuvant.

Tetanus toxoid: Clostridium tetani causes tetanus. Tetanus toxin can be processed to produce a protective toxoid. Toxoids are used in tetanus vaccines. Preferred tetanus toxoids are those obtained by treatment with formaldehyde. Tetanus toxoid can be obtained by growing C. tetani in growth medium, followed by formaldehyde treatment, ultrafiltration, and precipitation. The material may then be processed according to a method including sterile filtration and/or dialysis.

Hepatitis A virus antigens: Hepatitis A virus (HAV) is one of the known agents that cause viral hepatitis. The preferred HAV component is based on an inactivated virus, and inactivation can be achieved by treatment with formalin.

Hepatitis B virus (HBV) is one of the known agents that cause viral hepatitis. The main component of the capsid is a protein known as the HBV surface antigen, or more commonly HBsAg, which is typically a 226 amino acid polypeptide with a molecular weight of ~24 kDa. All existing hepatitis B vaccines contain HBsAg, and when this antigen is introduced into a normal vaccine, it stimulates the production of anti-HBsAg antibodies that protect against HBV infection.

For vaccine production, HBsAg was obtained in two ways: particulate antigen purification from the plasma of chronic hepatitis B carriers or protein expression using recombinant DNA techniques (eg, recombinant expression in yeast cells). Unlike native HBsAg (ie, as in a purified plasma product), yeast-expressed HBsAg is generally non-glycosylated, and this is the most preferred form of HBsAg for use in the present invention.

Haemophilus influenzae type b conjugated antigens: Haemophilus influenzae type b (Hib) causes bacterial meningitis. Hib vaccines are generally based on the capsular saccharide antigen, the production of which is well documented. The Hib saccharide may be conjugated to a carrier protein in order to increase its immunogenicity, especially in children. Typical carrier proteins are tetanus toxoid, diphtheria toxoid, CRM ₁₉₇ , H. influenzae protein D, and outer membrane protein complex from serogroup B meningococcus. /or full length PRP fragments. Hib conjugates may or may not be adsorbed to an aluminum salt adjuvant.

In one embodiment, the immunogenic composition of the invention further comprises a conjugated N. meningitidis serogroup Y (MenY) capsular saccharide and/or a conjugated N. meningitidis serogroup C (MenC) capsular saccharide.

In one embodiment, the immunogenic composition of the invention further comprises a conjugated N. meningitidis serogroup A (MenA) capsular saccharide, a conjugated N. meningitidis serogroup W135 (MenW135) capsular saccharide, a conjugated N. meningitidis serogroup Y (MenY) capsular saccharide, and/or a conjugated capsular saccharide N. meningitidis serogroup C (MenC).

In one embodiment, the immunogenic composition of the invention further comprises N. meningitidis serogroup W135 conjugated capsular saccharide (MenW135), N. meningitidis serogroup Y conjugated capsular saccharide (MenY), and/or N. meningitidis serogroup C conjugated capsular saccharide (MenC).

4 Adjuvant(s)

In some embodiments, the immunogenic composition disclosed herein may further comprise at least two or three adjuvants. The term "adjuvant" refers to a compound or mixture that enhances the immune response to an antigen. Antigens may act primarily as a delivery system, primarily as an immunomodulator, or have strong features of both. Acceptable adjuvants include those that are acceptable for use in mammals, including humans.

Examples of known acceptable delivery system type adjuvants that can be used in the human body include, but are not limited to, aluminum alum (e.g., aluminum phosphate, aluminum sulfate, or aluminum hydroxide), calcium phosphate, liposomes, oil-in-water emulsions, such as MF59 (4.3% w/v squalene, 0.5% w/v polysorbate 80 (Tween 80), 0.5% w/v sorbitan trioleate (Span 85)), emulsions water -in-oil, such as Montanide, and microparticles or nanoparticles of poly(D,L-lactide-co-glycolide) (PLG).

In one embodiment, the immunogenic composition disclosed herein contains aluminum salts (aluminum alum) as an adjuvant (eg, aluminum phosphate, aluminum sulfate, or aluminum hydroxide). In a preferred embodiment, the immunogenic composition disclosed herein contains aluminum phosphate or aluminum hydroxide as an adjuvant. In one embodiment, the immunogenic composition disclosed herein contains 0.1 mg/ml to 1 mg/ml or 0.2 mg/ml to 0.3 mg/ml of elemental aluminum as aluminum phosphate. In one embodiment, the immunogenic composition disclosed herein contains approximately 0.25 mg/ml of elemental aluminum as aluminum phosphate.

Examples of known acceptable immunomodulatory type adjuvants that can be used in humans include, but are not limited to, saponin extracts from the bark of the Aquilla tree (QS21, Quil A), TLR4 agonists such as MPL (monophosphoryl lipid A), 3DMPL (3- O-deacylated MPL) or GLA-AQ, LT/CT mutants, cytokines such as various interleukins (eg IL-2, IL-12) or GM-CSF, and the like.

et al. (1998) J. Leukocyte Biol. 64:713; WO 90/03184, WO 96/11711, WO 00/48630, WO 98/36772, WO 00/41720, WO 2006/134423 и WO 2007/026190) или GLA-EM, которые представляют собой комбинацию агониста TLR4 и эмульсии масло-в-воде.Examples of known acceptable immunomodulatory type adjuvants with both delivery and immune modulatory functions that can be used in humans include, but are not limited to, ISCOMS (see, e.g.,

et al. (1998) J. Leukocyte Biol. 64:713; WO 90/03184, WO 96/11711, WO 00/48630, WO 98/36772, WO 00/41720, WO 2006/134423 and WO 2007/026190) or GLA-EM, which are a combination of a TLR4 agonist and an oil- in water.

For veterinary applications, including but not limited to animal experiments, complete Freund's adjuvant (CFA), incomplete Freund's adjuvant (IFA), Emulsigen, N-acetyl-muramyl-L-threonyl-D-isoglutamine (thr- MDP), N-acetyl-nor-muramyl-L-alanyl-D-isoglutamine (CGP 11637, referred to as nor-MDP), N-acetylmuramyl-L-alanyl-D-isoglutaminyl-L-alanine-2-(1' -2'-dipalmitoyl-sn-glycero-3-hydroxyphosphoryloxy)-ethylamine (CGP 19835A, referred to as MTP-PE), and RIBI, which contains three components extracted from bacteria, monophosphoryl lipid A, trehalose dimycolate, and a cell wall backbone (MPL +TDM+CWS) in 2% squalene/Tween 80 emulsion.

Additional examples of adjuvants for enhancing the efficacy of pneumococcal vaccines as disclosed herein include, but are not limited to: (1) oil-in-water emulsion formulations (with or without other specific immunostimulatory agents such as muramyl peptides (see below) or components bacterial cell wall), such as for example (a) SAF containing 10% squalene, 0.4% Tween 80, 5% pluronic-blocked polymer L121, and thr-MDP either microfluidized in a submicron emulsion or shaken to form an emulsion with a large particle size, and (b) RIBI™ adjuvant system (RAS), (Ribi Immunochem, Hamilton, MT) containing 2% squalene, 0.2% Tween 80, and one or more bacterial cell wall components such as monophosphoryl lipid A (MPL ), trehalose dimycolate (TDM), and cell wall skeleton (CWS), preferably MPL+CWS (DETOX™); (2) saponin adjuvants such as QS21, STIMULON™ (Cambridge Bioscience, Worcester, MA), ABISCO® (Isconova, Sweden), or ISCOMATRIX® (Commonwealth Serum Laboratories, Australia) may be used, or particles formed therefrom, such as ISCOMs (Immunostimulatory Complexes), in which the ISCOMS may be devoid of additional detergent (eg WO 00/07621); (3) complete Freund's adjuvant (CFA) and incomplete Freund's adjuvant (IFA); (4) cytokines such as interleukins (eg IL-1, IL-2, IL-4, IL-5, IL-6, IL-7, IL-12 (eg WO 99/44636)), interferons ( eg, interferon gamma), macrophage colony stimulating factor (M-CSF), tumor necrosis factor (TNF), etc.; (5) monophosphoryl lipid A (MPL) or 3-O-deacylated MPL (3dMPL) (see e.g. GB-2220221, EP 0689454), optionally substantially in the absence of aluminum alum when used with pneumococcal saccharides (see e.g. WO 00 /56358); (6) combinations of 3dMPL with, for example, QS21 and/or oil-in-water emulsions (see, for example, EP 0835318, EP 0735898, EP 0761231); (7) polyoxyethylene ethers or polyoxyethylene esters (see, for example, WO 99/52549); (8) a polyoxyethylene sorbitan ester surfactant in combination with octoxynol (e.g. WO 01/21207) or a polyoxyethylene alkyl ether or ester surfactant in combination with at least one additional non-ionic surfactant an active substance such as octoxynol (eg WO 01/21152); (9) saponin and an immunostimulatory oligonucleotide (eg CpG oligonucleotide) (eg WO 00/62800); (10) an immunostimulant and a metal salt particle (see, for example, WO 00/23105); (11) saponin and an oil-in-water emulsion (eg WO 99/11241); (12) saponin (eg QS21) + 3dMPL + IM2 (optional + sterol) (eg WO 98/57659); (13) other substances that act as immunostimulatory agents to improve the effectiveness of the composition. Muramyl peptides include N-acetyl-muramyl-L-threonyl-D-isoglutamine (thr-MDP), N-25 acetyl-nor-muramyl-L-alanyl-D-isoglutamine (nor-MDP), N-acetylmuramyl-L-alanyl -D-isoglutarninyl-L-alanine-2-(1'-2'-dipalmitoyl-sn-glycero-3-hydroxyphosphoryloxy)-ethylamine MTP-PE), etc.

In one embodiment according to the present invention, the immunogenic composition as disclosed herein contains a CpG oligonucleotide as an adjuvant. CpG oligonucleotide as used herein refers to a CpG immunostimulatory oligodeoxynucleotide (CpG ODN) and, accordingly, these terms are used interchangeably unless otherwise indicated.

CpG immunostimulatory oligodeoxynucleotides contain one or more CpG immunostimulatory motifs that are unmethylated cytosine-guanine dinucleotides, if appropriate in certain preferred core contexts. The methylation status of the CpG immunostimulatory motif generally refers to the cytosine residue in the dinucleotide. An immunostimulatory oligonucleotide containing at least one unmethylated CpG dinucleotide is an oligonucleotide that contains a 5' unmethylated cytosine phosphate bonded to a 3' guanine and that activates the immune system by binding to Toll-like receptor 9 (TLR-9 ). In another embodiment, the immunostimulatory oligonucleotide may contain one or more methylated CpG dinucleotides that will activate the immune system via TLR9, but not as much as if the CpG motif(s) were/were unmethylated(s).

CpG immunostimulatory oligonucleotides may contain one or more palindromes, which in turn may include a CpG dinucleotide. CpG oligonucleotides have been described in a number of issued patents, published patent applications, and other publications, including US Pat. Nos. 6,194,388; 6,207,646; 6,214,806; 6,218,371; 6,239,116; and 6,339,068.

In one embodiment according to the present invention, the immunogenic composition as disclosed herein comprises any of the CpG oligonucleotides described on page 3, line 22 to page 12, line 36 of WO 2010/125480.

Various classes of CpG immunostimulatory oligonucleotides have been identified. They are referred to as A, B, C and P class, and are described in more detail from page 3, line 22 to page 12, line 36, WO 2010/125480. The methods of the invention encompass the use of these various classes of CpG immunostimulatory oligonucleotides.

In one embodiment according to the present invention, the immunogenic composition as disclosed herein comprises a class A CpG oligonucleotide. Preferably, the "class A" CpG oligonucleotide according to the invention has the following nucleic acid sequence: 5' GGGGACGACGTCGTGGGGGGG 3' (SEQ ID NO : one). Some non-limiting examples of A-class oligonucleotides include: 5' G*G*G_G_A_C_G_A_C_G_T_C_G_T_G_G*G*G*G*G*G 3' (SEQ ID NO: 2); where ^"*" refers to a phosphorothioate bond and "_" refers to a phosphodiester bond. In one embodiment according to the present invention, the immunogenic composition as disclosed herein comprises a class B CpG oligonucleotide. In one embodiment, the CpG oligonucleotide for use in the present invention is a class B CpG oligonucleotide represented by at least the formula:

5' X ₁ X ₂ CGX ₃ X ₄ 3',

where X1, X2, X3, and X4 are nucleotides. In one embodiment, X ₂ is adenine, guanine, or thymine. In another embodiment, X ₃ is cytosine, adenine, or thymine.

The class B CpG oligonucleotide sequences of the invention are those outlined above and also disclosed in WO 96/02555, WO 98/18810 and US Pat. Nos. 6,194,388; 6,207,646; 6,214,806; 6,218,371; 6,239,116 and 6,339,068. Example sequences include, but are not limited to, those disclosed in these recent applications and patents.

In one embodiment, a "B-class" CpG oligonucleotide of the invention has the following nucleic acid sequence:

In any of these sequences, all bonds may be phosphorothioate bonds. In another embodiment, in any of these sequences, one or more linkages may be phosphodiester, preferably from the "C" and "G" motif of the CpG, creating a semi-soft CpG oligonucleotide. In any of these sequences, ethyl-uridine or halogen may replace 5' T; examples of halogen substitutions include, but are not limited to, bromine-uridine or iodine-uridine substitutions. Some non-limiting examples of B-class oligonucleotides include:

where ^"*" refers to a phosphorothioate bond.

In one embodiment according to the present invention, the immunogenic composition as disclosed herein comprises a C class CpG oligonucleotide. In one embodiment, the "C class" CpG oligonucleotides of the invention have the following nucleic acid sequence:

In any of these sequences, all bonds may be phosphorothioate bonds. In another embodiment, in any of these sequences, one or more of the bonds may be phosphodiester, preferably from the "C" and "G" of the CpG motif, creating a semi-soft CpG oligonucleotide.

Some non-limiting examples of C-class oligonucleotides include:

where ^"*" refers to a phosphorothioate bond and "_" refers to a phosphodiester bond.

In any of these sequences, ethyl-uridine or halogen may replace 5' T; examples of halogen substitutions include, but are not limited to, bromine-uridine or iodine-uridine substitutions.

In one embodiment according to the present invention, the immunogenic composition as disclosed herein comprises a CpG class P oligonucleotide. In one embodiment, the CpG oligonucleotide for use in the present invention is a CpG class P oligonucleotide containing a 5' TLR activation domain and, at least two palindromic regions, where one palindromic region is a 5' palindromic region of at least 6 nucleotides in length and associated with a 3' palindromic region of at least 8 nucleotides in length, or directly, or by means of a spacer, where the oligonucleotide comprises at least a YpR dinucleotide. In one embodiment, said oligonucleotide is not T*C_G*T*C_G*A*C_G*T*T*C_G*G*C*G*C_G*C*G*C*C*G (SEQ ID NO: 27). In one embodiment, the class P CpG oligonucleotide comprises at least an unmethylated CpG dinucleotide. In another embodiment, the TLR activation domain is TCG, TTCG, TTTCG, TYpR, TTYpR, TTTYpR, UCG, UUCG, UUUCG, TTT, or TTTT. In yet another embodiment, the TLR activation domain is within the 5' palindromic region. In another embodiment, the TLR activation domain is located directly in the 5' to 5' palindromic region.

In one embodiment, the "P-class" CpG oligonucleotides of the invention have the following nucleic acid sequence: 5' TCGTCGACGATCGGCGCGCGCCG 3' (SEQ ID NO: 39).

In these sequences, all bonds may be phosphorothioate bonds. In another embodiment, one or more linkages can be phosphodiester, preferably from the "C" and "G" motif of the CpG, creating a semi-soft CpG oligonucleotide. In any of these sequences, ethyl-uridine or halogen may replace 5' T; examples of halogen substitutions include, but are not limited to, bromine-uridine or iodine-uridine substitutions. A non-limiting example of P-class oligonucleotides include: 5' T*C_G*T*C_G*A*C_G*A*T*C_G*G*C*G*C_G*C*G*C*C*G 3' (SEQ ID NO: 40)

where ^"*" refers to a phosphorothioate bond and "_" refers to a phosphodiester bond.

In one embodiment, the oligonucleotide includes at least a phosphorothioate bond. In another embodiment, all internucleotide bonds of the oligonucleotide are phosphorothioate bonds. In another embodiment, the oligonucleotide includes at least a phosphodiester-like bond. In another embodiment, the phosphodiester-like bond is a phosphodiester bond. In another embodiment, the lipophilic group is conjugated to an oligonucleotide. In one embodiment, the lipophilic group is cholesterol.

In one embodiment, all internucleotide bonds of the CpG oligonucleotides disclosed herein are phosphodiester bonds ("soft" oligonucleotides as described in WO 2007/026190). In another embodiment, the CpG oligonucleotides of the invention are resistant to degradation (eg, are stabilized). "Stabilized oligonucleotide" refers to an oligonucleotide that is relatively resistant to in vivo degradation (eg, by an exo- or endo-nuclease). Nucleic acid stabilization can be accomplished by backbone modifications. Oligonucleotides having phosphorothioate bonds provide maximum activity and protection of the oligonucleotide from destruction by intracellular exo- and endo-nucleases.

Immunostimulatory oligonucleotides may have a chimeric backbone that has combinations of phosphodiester and phosphorothioate linkages. For purposes of the present invention, a chimeric backbone refers to a partially stabilized backbone, wherein at least one internucleotide bond is phosphodiester or phosphodiester-like, and wherein at least one other internucleotide bond is a stabilized internucleotide bond, wherein at least , one phosphodiester or phosphodiester-like bond and at least one stabilized bond are different. When the phosphodiester bond is predominantly within the CpG motif, such molecules are referred to as "semi-soft", as described in WO 2007/026190.

Other modified oligonucleotides include combinations of phosphodiester, phosphorothioate, methylphosphonate, methylphosphorothioate, phosphorodithioate, and/or p-ethoxy linkages.

A mixed backbone modified with ODN can be synthesized as described in WO 2007/026190.

The size of the CpG oligonucleotide (ie, the number of nucleotide residues along the length of the oligonucleotide) can also contribute to the stimulatory activity of the oligonucleotide. To facilitate entry into cells, the CpG oligonucleotide of the invention preferably has a minimum length of 6 nucleotide residues. Oligonucleotides of any size greater than 6 nucleotides (even many thousands of base pairs long) are capable of inducing an immune response if enough immunostimulatory motifs are present, since larger oligonucleotides are degraded within cells. In certain embodiments, the CpG oligonucleotides are 6 to 100 nucleotides in length, preferably 8 to 30 nucleotides in length. In important embodiments, the nucleic acids and oligonucleotides of the invention are not plasmids or expression vectors.

In one embodiment, the CpG oligonucleotide disclosed herein contains substitutions or modifications, such as in bases and/or sugars, as described in paragraphs 134-147 of WO 2007/026190.

In one embodiment, the CpG oligonucleotide of the present invention is chemically modified. Examples of chemical modifications are known to the skilled artisan and are described, for example, in Uhlmann et al. (1990) Chem. Rev. 90:543; S. Agrawal, Ed., Humana Press, Totowa, USA 1993; Crooke et al. (1996) Anna. Rev. Pharmacol. Toxicol. 36:107-129; and Hunziker et al. (1995) Mod. Synth. Methods 7: 331-417. The oligonucleotide according to the invention may have one or more modifications, where each modification is located in a specific phosphodiester internucleoside bridge, and/or in a specific β-D-ribose unit, and/or in a specific position of the natural nucleoside base compared to the oligonucleotide of the same the same sequence that is made up of natural DNA or RNA.

In some embodiments according to the invention, CpG-containing nucleic acids can be simply mixed with immunogenic carriers in accordance with methods known to those skilled in the art (see, for example, WO 03/024480).

In a specific embodiment according to the present invention, any immunogenic composition disclosed herein contains from 2 μg to 100 mg of CpG oligonucleotide, preferably from 0.1 mg to 50 mg of CpG oligonucleotide, preferably from 0.2 mg to 10 mg CpG oligonucleotide, preferably 0.3 mg to 5 mg CpG oligonucleotide, preferably 0.3 mg to 5 mg CpG oligonucleotide, more preferably 0.5 to 2 mg CpG oligonucleotide, more preferably 0.75 to 1.5 mg CpG oligonucleotide. In a preferred embodiment, any immunogenic composition disclosed herein contains approximately 1 mg of CpG oligonucleotide.

5 Formulation

The immunogenic composition of the invention may be formulated in liquid form (ie solutions or suspensions) or in lyophilized form. Liquid preparations can advantageously be administered directly from their packaged form and are thus ideally suited for injection without the need for reconstitution in an aqueous medium as is otherwise required for the lyophilized compositions of the invention.

The formulation of the immunogenic composition according to the present invention can be carried out using methods generally accepted in this field. For example, individual pneumococcal conjugates may be formulated with a physiologically acceptable carrier to form a composition. Examples of such carriers include, but are not limited to, water, buffered saline, polyols (eg, glycerol, propylene glycol, liquid polyethylene glycol), and dextrose solutions.

The present invention provides an immunogenic composition containing any combination of the glycoconjugates disclosed herein and a pharmaceutically acceptable excipient, carrier, or diluent.

In one embodiment, the immunogenic composition according to the invention is in liquid form, preferably in aqueous liquid form.

An immunogenic composition according to the disclosure may contain one or more of a buffer, a salt, a divalent cation, a nonionic deirgent, a cryoprotectant such as a sugar, and an antioxidant such as a free radical scavenger, or a chelating agent, or any of several combinations thereof.

In one embodiment, the immunogenic composition according to the invention contains a buffer. In one embodiment, said buffer has a pKa of about 3.5 to about 7.5. In some embodiments, the buffer is a phosphate, succinate, histidine, or citrate. In certain embodiments, the buffer is succinate at a final concentration of 1 mM to 10 mM. In one particular embodiment, the final concentration of succinate buffer is approximately 5 mM.

In one embodiment, the immunogenic composition according to the invention contains a salt. In some embodiments, the salt is selected from the group consisting of magnesium chloride, potassium chloride, sodium chloride, and combinations thereof. In one candy embodiment, the salt is sodium chloride. In one specific embodiment, the immunogenic composition according to the invention contains sodium chloride in an amount of 150 mm.

In one embodiment, the immunogenic composition according to the invention contains a surfactant. In one embodiment, the surfactant is selected from the group consisting of polysorbate 20 (TWEEN™20), polysorbate 40 (TWEEN™40), polysorbate 60 (TWEEN™60), polysorbate 65 (TWEEN™65), polysorbate 80 ( TWEEN™80), polysorbate 85 (TWEEN™85), TRITON™ N-101, TRITON™ X-100, oxoxynol 40, nonoxynol-9, triethanolamine, triethanolamine polypeptidoleate, polyoxyethylene-660 hydroxystearate (PEG-15, Solutol H 15), polyoxyethylene 35-ricinoleate (CREMOPHOR® EL), soy lecithin and poloxamer. In one particular embodiment, the surfactant is polysorbate 80. In some of these embodiments, the final concentration of polysorbate 80 in the formulation is at least 0.0001% to 10% polysorbate 80 w/w wt.). In some of these embodiments, the final concentration of polysorbate 80 in the formulation is at least 0.001% to 1% polysorbate 80 w/w (w/w). In some of these embodiments, the final concentration of polysorbate 80 in the formulation is at least 0.01% to 1% polysorbate 80 w/w (w/w). In other embodiments, the final concentration of polysorbate 80 in the formulation is 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08 %, 0.09% or 0.1% polysorbate 80 (w/w). In another embodiment, the final concentration of polysorbate 80 in the formulation is 1% polysorbate 80 (w/w).

In certain embodiments, the immunogenic composition of the invention has a pH of 5.5 to 7.5, more preferably a pH of 5.6 to 7.0, even more preferably a pH of 5.8 to 6.0.

In one embodiment, the present invention provides for a container filled with any of the immunogenic compositions disclosed herein. In one embodiment, the container is selected from the group consisting of a vial, syringe, flask, fermenter, bioreactor, bag, jar, ampoule, cartridge, and disposable pen. In certain embodiments, the container is siliconised.

In one embodiment, the container according to the present invention is made of glass, metals (eg, steel, stainless steel, aluminum, etc.) and/or polymers (eg, thermoplastics, elastomers, thermoplastic elastomers). In one embodiment, the container according to the present invention is made of glass.

In one embodiment, the present invention provides for a syringe filled with any of the immunogenic compositions disclosed herein. In certain embodiments, the syringe is siliconized and/or made of glass.

A typical dose of an immunogenic composition according to the invention for injection has a volume of 0.1 ml to 2 ml, more preferably 0.2 ml to 1 ml, even more preferably a volume of about 0.5 ml.

Therefore, the container or syringe as defined above is filled with a volume of 0.1 ml to 2 ml, more preferably 0.2 ml to 1 ml, even more preferably a volume of approximately 0.5 ml of any immunogenic composition as defined herein. .

6 Use of immunogenic compositions according to the invention

In one embodiment, the immunogenic compositions disclosed herein are for use as a drug.

The immunogenic composition described herein can be used in various therapeutic or prophylactic methods to prevent, treat, or ameliorate a bacterial infection, disease, or condition in a subject. In particular, the immunogenic composition described herein can be used to prevent, treat, or attenuate a S. pneumoniae infection, disease, or condition in a subject.

Thus, in one aspect, the invention provides a method of preventing, treating, or ameliorating an infection, disease, or condition associated with S. pneumoniae in a subject, comprising administering to the subject an immunologically effective amount of an immunogenic composition of the invention.

In some such embodiments, the infection, disease, or condition is selected from the group consisting of pneumonia, sinusitis, otitis media, acute otitis media, meningitis, bacteremia, sepsis, pleural empyema, conjunctivitis, osteomyelitis, septic arthritis, endocarditis, peritonitis , pericarditis, mastoiditis, cellulitis, soft tissue infections and brain abscess.

In one embodiment, the invention provides a method of inducing an immune response to S. pneumoniae in a subject, comprising administering to the subject an immunologically effective amount of an immunogenic composition of the invention.

In one embodiment, the immunogenic composition disclosed herein is for use as a vaccine. In such embodiments, the immunogenic composition described herein can be used to prevent S. pneumoniae infection in a subject. Thus, in one aspect, the invention provides a method of preventing S. pneumoniae infection in a subject, comprising administering to the subject an immunologically effective amount of an immunogenic composition of the invention. In some such embodiments, the infection is selected from the group consisting of pneumonia, sinusitis, otitis media, acute otitis media, meningitis, bacteremia, sepsis, pleural empyema, conjunctivitis, osteomyelitis, septic arthritis, endocarditis, peritonitis, pericarditis, mastoiditis , cellulitis, soft tissue infections and brain abscess. In one aspect, the subject to be vaccinated is a mammal such as a human, cat, sheep, pig, horse, cow, or dog.

In one aspect, the immunogenic composition disclosed herein is for use in a method for preventing, treating, or ameliorating an infection, disease, or condition associated with S. pneumoniae in a subject. In some such embodiments, the infection, disease or condition is selected from the group consisting of pneumonia, sinusitis, otitis media, acute otitis media, meningitis, bacteremia, sepsis, pleural empyema, conjunctivitis, osteomyelitis, septic arthritis, endocarditis, peritonitis, pericarditis, mastoiditis, cellulitis, soft tissue infection and brain abscess.

In one embodiment, the immunogenic composition disclosed herein is for use as a vaccine. In such embodiments, the immunogenic composition described herein can be used to prevent S. pneumoniae infection in a subject. Thus, in one aspect, the immunogenic composition disclosed herein is for use in a method for preventing S. pneumoniae infection in a subject. In some such embodiments, the infection is selected from the group consisting of pneumonia, sinusitis, otitis media, acute otitis media, meningitis, bacteremia, sepsis, pleural empyema, conjunctivitis, osteomyelitis, septic arthritis, endocarditis, peritonitis, pericarditis, mastoiditis, cellulitis, soft tissue infections and brain abscess. In one aspect, the subject to be vaccinated is a mammal such as a human, cat, sheep, pig, horse, cow, or dog.

The immunogenic composition according to the present invention can be used to protect or treat a human suffering from pneumococcal infection by administering the immunogenic composition using systemic or mucosal administration. In one embodiment, the immunogenic composition disclosed herein is administered by intramuscular, intraperitoneal, intradermal, or subcutaneous routes. In one embodiment, the immunogenic composition disclosed herein is administered using intramuscular, intraperitoneal, intradermal, or subcutaneous injection. In one embodiment, the immunogenic composition disclosed herein is administered using intramuscular or subcutaneous injection.

In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above), when administered to a subject, is capable of inducing the formation of antibodies capable of binding with S. pneumoniae serotype 15B, 15A and/or 15C as measured using a standard ELISA assay. In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates of section 1.3.4 above), when administered to a subject, is capable of inducing the formation of antibodies capable of binding to S. pneumoniae serotypes 15B and 15C as measured using a standard ELISA assay.

In the ELISA (enzyme-linked immunosorbent assay) method, antibodies from the sera of vaccinated subjects are incubated with polysaccharides that are adsorbed onto a solid support. Bound antibodies were detected using enzyme-conjugated secondary detection antibodies.

In one embodiment, said standard ELISA assay is a standardized (WHO) ELISA assay as defined by the WHO in 'Training manual for Enzyme linked immunosorbent assay for the quantitation of Streptococcus pneumoniae serotype specific IgG (Pn PS ELISA).' (accessible at http://www.vaccine.uab.edu/ELISA%20protocol.pdf; accessed on March 31 ^st , 2014).

ELISA determines typical antibodies to a specific anti-S IgG. pneumoniae capsular polysaccharide (PS) present in human serum. When dilutions of human serum are added to type-specific capsule PS-coated microtiter plates, antibodies specific for this capsular PS bind to the microtiter plates. Plate-bound antibodies are detected using a goat anti-human IgG labeled with alkaline phosphatase followed by p-nitrophenyl phosphate substrate. The optical density of the colored final product is proportional to the amount of anti-capsular PS antibody present in the serum.

In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) is capable of eliciting human IgG antibodies that are capable of binding to the polysaccharide S. pneumoniae serotype 15B at a concentration of at least 0.05, 0.1, 0.2, 0.3, 0.35, 0.4, or 0.5 µg/mL, as determined by ELISA analysis.

In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) is capable of eliciting human IgG antibodies that are capable of binding to S. pneumoniae serotype 15C polysaccharide at a concentration of at least 0.05, 0.1, 0.2, 0.3, 0.35, 0.4, or 0.5 µg/ml, as determined by ELISA analysis .

In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) is capable of eliciting human IgG antibodies that are capable of binding to polysaccharide of S. pneumoniae serotypes 15B and 15C at a concentration of at least 0.05, 0.1, 0.2, 0.3, 0.35, 0.4, or 0.5 µg/mL, as determined by ELISA analysis.

In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above), when administered to a subject, is capable of inducing the formation of antibodies capable of eradication of S. pneumoniae serotype 15B assay for opsonophagocytic activity as disclosed herein (eg, in the OPA assay of Example 12).

In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above), when tested in an OPA assay as disclosed herein (eg, in the OPA assay of Example 12) has an OPA titer greater than the OPA titer obtained with unconjugated native S. pneumoniae serotype 15B capsular polysaccharide.

In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above), when administered to a subject, is capable of inducing the formation of antibodies capable of the destruction of S. pneumoniae serotype 15C analysis of opsonophagocytic activity, as disclosed in this document (for example, in the OPA analysis of example 12). In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) when tested in an OPA assay as disclosed herein (eg, in the OPA assay of Example 12) has an OPA titer greater than the OPA titer obtained with unconjugated native S. pneumoniae serotype 15B capsular polysaccharide.

The pneumococcal opsonophagocytic activity assay (OPA), which measures the killing of S. pneumoniae cells using phagocytic effector cells in the presence of a functional antibody and complement, is considered to be an important surrogate for evaluating the effectiveness of pneumococcal vaccines.

Opsonophagocytic activity (OPA) assays can be performed by incubating together a mixture of Streptococcus pneumoniae cells, heat-inactivated human serum to be tested, differentiated HL-60 cells (phagocytes), and a source of exogenous complement (eg, baby rabbit complement). Opsonophagocytosis occurs during incubation, and bacterial cells that are coated with antibody and complement die during opsonophagocytosis. The colony forming units (CFU) of surviving bacteria that escape opsonophagocytosis are determined by plating the assay mixture. The OPA titer is defined as the reciprocal dilution that results in a 50% reduction in bacteria compared to control wells without test serum. The OPA titer is interpolated from two dilutions that cover a given 50% kill cutoff.

A titer endpoint of 1:8 or greater is considered a positive result in this type of OPA kill.

In one embodiment, an immunogenic composition according to the present invention containing at least one glycoconjugate from S. pneumoniae serotype 15B (such as glycoconjugates from section 1.3.4 above) is capable of inducing a titer of at least 1:8 against S. pneumoniae serotype 15B in at least 50% of subjects as determined by opsonophagocytic killing activity (OPA) analysis. In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) is capable of inducing a titer of at least 1:8 vs. S. pneumoniae serotype 15B in at least 60%, 70%, 80%, 90%, or at least 93% of subjects, as determined by opsonophagocytic killing activity (OPA) analysis.

In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) is capable of inducing a titer of at least 1:8 vs. S. pneumoniae serotype 15C in at least 50% of subjects, as determined by opsonophagocytic killing activity (OPA) analysis. In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) is capable of inducing a titer of at least 1:8 vs. S. pneumoniae serotype 15C in at least 60%, 70%, 80%, 90%, or at least 95% of subjects as determined by opsonophagocytic killing activity (OPA) analysis.

In a further aspect, the present invention provides a method for treating or preventing S. pneumoniae infection, disease, or condition associated with S. pneumoniae serotype 15A, 15B, and/or 15C in a subject, wherein the method comprises the step of administering a therapeutically or prophylactically effective amount of any immunogenic compositions according to the present invention containing at least one glycoconjugate from S. pneumoniae serotype 15B (such as glycoconjugates from section 1.3.4 above). In one embodiment, an immunogenic composition of the present invention containing at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above), when administered to a subject, induces the formation of antibodies capable of binding to S. pneumoniae serotype 15B, 15A and/or 15C. In one embodiment, an immunogenic composition of the present invention comprising at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above), when administered to a subject, induces the production of antibodies capable of killing S Pneumoniae serotype 15B, 15C and/or 15A in an opsonophagocytic activity assay as disclosed herein (eg, in the OPA assay of Example 12).

One embodiment according to the disclosure provides a method of protecting a subject against S. pneumoniae serotype 15C infection, or a method of preventing S. pneumoniae serotype 15C infection, or a method of reducing the severity or delaying the onset of at least one symptom associated with S. Pneumoniae serotype 15C, wherein the methods comprise administering to the subject an immunogenic amount of any of the immunogenic compositions of the present invention containing at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates of section 1.3.4 above). One embodiment according to the disclosure provides a method for treating or preventing a S. pneumoniae infection, disease, or condition associated with S. pneumoniae serotype 15A, 15B, and/or 15C (preferably 15B and/or 15C, more preferably 15B) in a subject, wherein the method comprises the step of administering a therapeutically or prophylactically effective amount of any of the immunogenic compositions of the present invention containing at least one S. pneumoniae serotype 15B glycoconjugate (such as the glycoconjugates of section 1.3.4 above) to the subject. Another embodiment provides a method for treating or preventing S. pneumoniae infection, disease, or condition associated with S. pneumoniae serotype 15A, 15B, and/or 15C (preferably 15B and/or 15C, more preferably 15B) in a subject, wherein the method comprises generating a drug a polyclonal or monoclonal antibody from any of the immunogenic compositions of the present invention containing at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above), and using said antibody preparation to provide passive immunity to the subject.

In one embodiment, the disclosure relates to the use of any of the immunogenic compositions of the present invention containing at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) for the manufacture of a drug for protection subject against S. pneumoniae infection, and/or preventing S. pneumoniae infection, and/or reducing the severity or delaying the onset of at least one symptom associated with S. pneumoniae infection and/or protecting the subject against S. pneumoniae infection. Pneumoniae serotype 15A, 15B and/or 15C (preferably 15B and/or 15C, more preferably 15B), and/or prevention of S. pneumoniae serotype 15A, 15B and/or 15C infection (preferably 15B and/or 15C, more preferably 15B) , and/or reduce the severity or delay the onset of at least one symptom associated with S. pneumoniae serotype 15A, 15B, and/or 15C infection (preferably but 15V and/or 15C, more preferably 15V).

In one embodiment, the disclosure relates to the use of any of the immunogenic compositions of the present invention containing at least one glycoconjugate from S. pneumoniae serotype 15B (such as the glycoconjugates from section 1.3.4 above) to protect the subject against infection S. pneumoniae and/or preventing S. pneumoniae infection and/or reducing the severity or delaying the onset of at least one symptom associated with S. pneumoniae infection and/or protecting the subject against S. pneumoniae serotype 15A infection , 15B and/or 15C (preferably 15B and/or 15C, more preferably 15B) and/or preventing infection with S. Pneumoniae serotype 15A, 15B and/or 15C (preferably 15B and/or 15C, more preferably 15B), and/or reduce the severity or delay the onset of at least one symptom associated with infection with S. pneumoniae serotype 15A, 15B and/or 15C (preferably 15B and/or 15C, more preferably 15V).

7 Subject to be treated with an immunogenic composition according to the invention

As disclosed herein, the immunogenic composition described herein can be used in various therapeutic or prophylactic methods to prevent, treat, or ameliorate a bacterial infection, disease, or condition in a subject.

In a preferred embodiment, said subject is a human. In the most preferred embodiment, said subject is a neonate (i.e., under the age of three months), an infant (i.e., between the ages of 3 months and one year) or a toddler (i.e., between the ages of one and four years) .

In one embodiment, the immunogenic composition disclosed herein is for use as a vaccine.

In such an embodiment, the subject to be vaccinated may be less than 1 year of age. For example, the subject to be vaccinated may be about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, or about 12 months of age. In one embodiment, the subject to be vaccinated is about 2, about 4, or about 6 months old. In another embodiment, the subject to be vaccinated is less than 2 years of age. For example, the subject to be vaccinated may be from about 12 to about 15 months of age. In some cases, only one dose of the immunogenic composition according to the invention is needed, but in some cases, a second, third or fourth dose may be given (see section 8 below).

In one embodiment according to the present invention, the subject to be vaccinated is an adult 50 years of age or older, more preferably an adult 55 years of age or older. In one embodiment, the subject to be vaccinated is an adult 65 years of age or older, 70 years of age or older, 75 years of age or older, or 80 years of age or older.

In one embodiment, the subject to be vaccinated is an individual with impaired immunological reactivity, in particular a human. An individual with impaired immunological reactivity is generally defined as an individual who demonstrates an impaired or reduced ability to maintain normal humoral or cellular defenses to elicit immunity from infectious agents.

In one embodiment according to the present invention, the subject with impaired immunological reactivity to be vaccinated suffers from a disease or condition that impairs the immune system and results in an antibody response that is insufficient to protect against or treat pneumococcal disease.

In one embodiment, said disease is a primary immunodeficiency disorder. Preferably, said primary immunodeficiency disorder is selected from the group consisting of: combined T and B cell immunodeficiencies, antibody deficiencies, well defined syndromes, immune dysregulatory diseases, phagocyte disorders, congenital immune deficiencies, autoinflammatory disorders, and complement defects. In one embodiment, said primary immunodeficiency disorder is selected from those disclosed on page 24, line 11 to page 25, line 19 of WO 2010/125480.

In a specific embodiment of the present invention, the subject with impaired immunological reactivity to be vaccinated suffers from a disease selected from the group consisting of: HIV infection, acquired immunodeficiency syndrome (AIDS), cancer, chronic heart or lung failure, congestive heart failure, diabetes mellitus, chronic liver disease, alcoholism, cirrhosis of the liver, spinal fluid leakage, cardiomyopathy, chronic bronchitis, emphysema, chronic obstructive pulmonary disease (COPD), spleen dysfunction (eg, sickle cell anemia), lack of spleen function (asplenia), malignancy blood, leukemia, multiple myeloma, Hodgkin's disease, lymphoma, kidney failure, nephrotic syndrome and asthma.

In one embodiment, according to the present invention, the subject with impaired immunological reactivity, which should be vaccinated, suffers from malnutrition.

In a specific embodiment of the present invention, the subject with impaired immunological reactivity to be vaccinated is taking a drug or treatment that reduces the body's resistance to infection. In one embodiment, said drug is selected from one of those disclosed on page 26 line 33 to page 26 line 4 of WO 2010/125480.

In the candy embodiment of the present invention, the subject with impaired immunological reactivity to be vaccinated is a smoker.

In the candy embodiment of the present invention, the subject with impaired immunological reactivity to be vaccinated has a white blood cell count (leukocyte count) of less than 5×10 ⁹ cells per liter, or less than 4×10 ⁹ cells per liter, or less than 3×10 ⁹ cells per liter, or less than 2×10 ⁹ cells per liter, or less than 1×10 ⁹ cells per liter, or less than 0.5×10 ⁹ cells per liter, or less than 0.3×10 ⁹ cells per liter, or below 0.1×10 ⁹ cells per liter.

White blood cell count (leukocyte count): The number of white blood cells (WBC) in the blood. WBC is usually measured as part of the CBC (Complete Blood Count). White blood cells are infection-fighting cells in the blood and are different from the fas (oxygen-carrying) blood cells known as red blood cells. There are different types of white blood cells, including neutrophils (polymorphonuclear leukocytes; PMN), band cells (slightly immature neutrophils), T-type lymphocytes (T-cells), B-type lymphocytes (B-cells), monocytes, eosinophils, and basophils. . All types of white blood cells are reflected in the number of white blood cells. The normal range for white blood cell counts is typically 4,300 to 10,800 cells per cubic millimeter of blood. This may also be referred to as the white blood cell count and may be expressed in international units as 4.3-10.8×10 ⁹ cells per liter.

In a specific embodiment of the present invention, the subject with impaired immunological reactivity to be vaccinated suffers from neutropenia. In a specific embodiment of the present invention, the subject with impaired immunological reactivity to be vaccinated has a neutrophil count below 2×10 ⁹ cells per liter, or below 1×10 ⁹ cells per liter, or below 0.5×10 ⁹ cells per liter , or below 0.1×10 ⁹ cells per liter, or below 0.05×10 ⁹ cells per liter.

A low white blood cell count or "neutropenia" is a condition characterized by an abnormally low level of neutrophils in the circulating blood. Neutrophils are a specific type of white blood cell that help prevent and fight infections. The most common reason that cancer patients suffer from neutropenia is a side effect of chemotherapy. Chemotherapy-induced neutropenia increases the risk of patient infection and disrupts cancer treatment.

In a specific embodiment of the present invention, the subject with impaired immunological reactivity to be vaccinated has a CD4+ cell count below 500/mm ³ , or a CD4+ cell count below 300/mm ³ , or a CD4+ cell count below 200/mm ³ , a CD4+ cell count below 100/mm ³ , CD4+ cell count below 75/mm ³ , or CD4+ cell count below 50/mm ³ .

CD4 cell studies are generally reported as cell counts in mm ³ . The normal CD4 count is 500 to 1600, and the CD8 count is 375 to 1100. The CD4 count drops dramatically in people with HIV.

In one embodiment according to the invention, any of the subjects with impaired immunological reactivities disclosed herein is a male human or a female human.

8 Mode

In some cases, only one dose of the immunogenic composition according to the invention is needed, but in some circumstances, such as in states of greater immune deficiency, a second, third or fourth dose may be given. Following a primary vaccination, subjects may receive one or more booster immunizations, adequately spaced.

In one embodiment, the vaccination schedule with an immunogenic composition according to the invention is a single dose. In a specific embodiment, said single dose schedule is for a healthy subject at least 2 years of age.

In one embodiment, the schedule for vaccination with an immunogenic composition according to the invention is a multi-dose schedule. In a particular embodiment, said multi-dose schedule consists of a series of 2 doses separated by an interval of about 1 month to about 2 months. In a specific embodiment, said multi-dose schedule consists of a series of 2 doses separated by an interval of approximately 1 month, or a series of 2 doses separated by an interval of approximately 2 months.

In another embodiment, said multi-dose schedule consists of a series of 3 doses separated by an interval of about 1 month to about 2 months. In another embodiment, said multi-dose schedule consists of a series of 3 doses separated by an interval of approximately 1 month, or a series of 3 doses separated by an interval of approximately 2 months.

In another embodiment, said multi-dose schedule consists of a series of 3 doses separated by an interval of about 1 month to about 2 months followed by four doses from about 10 months to about 13 months after the first dose. In another embodiment, said multiple dose schedule consists of a series of 3 doses separated by an interval of approximately 1 month followed by four doses from approximately 10 months to approximately 13 months after the first dose, or a series of 3 doses separated by an interval of approximately 2 months followed by four doses from about 10 months to about 13 months after the first dose.

In one embodiment, the multi-dose schedule consists of at least one dose (eg, 1, 2, or 3 doses) in the first year of life, followed by at least one dose at toddler age.

In one embodiment, the multi-dose schedule consists of a series of 2 or 3 doses separated by an interval of about 1 month to about 2 months (e.g., 28-56 days between doses), starting at 2 months of age, and followed by a dose to the infant. at the age of 12-18 months. In one embodiment, said multi-dose schedule consists of a series of 3 doses spaced about 1 month to about 2 months apart (e.g., 28-56 days between doses), starting at 2 months of age, and followed by a dose to an infant at aged 12-15 months. In another embodiment, said multi-dose schedule consists of a series of 2 doses spaced about 2 months apart, starting at 2 months of age, and followed by a dose to a 12-18 month old infant.

In one embodiment, the multi-dose schedule consists of a 4-dose series of vaccine at 2, 4, 6, and 12-15 months of age.

In one embodiment, the first dose is given at 0 days of age and one or more boosts are given at intervals that range from about 2 to about 24 weeks, preferably at a dosing interval of 4-8 weeks.

In one embodiment, the first dose is given at 0 days of age and a boost is given approximately 3 months later.

As used herein, the term "about" means within a statistically significant range of value, such as a specified concentration range, time frame, molecular weight, temperature, or pH. Such a range may be within an order of magnitude, typically within 20%, more typically within 10%, and even more typically within 5% or within 1% of a given value or range. Sometimes, such a range may be within the experimental error of typical standard methods used to measure and/or determine a setpoint or range. The tolerance covered by the term "approximately" will depend on the particular system under study, and can be easily estimated by one of ordinary skill in the art. Whenever a range is read within this application, each integer of an integer within the range is also considered as an embodiment of the invention.

The terms "comprising", "comprise" and "comprises" in this document are intended by the inventors to be optionally interchangeable with the terms "comprising in essence", "comprising in essence", "comprising in essence", "consisting of', "consist of' and "consists of', respectively, in each example.

All references or patent applications cited in this patent specification are incorporated herein by reference. The invention is illustrated in the attached examples. The following examples are performed using standard techniques that are well known and routine to those skilled in the art, except where otherwise described in detail. The examples illustrate, but do not limit, the invention.

EXAMPLE

Example 1 General Method for the Preparation of eTEC Linked Glycoconjugates

Saccharide activation and thiolation of cystamine d and hydrochloride

The saccharide is dissolved in anhydrous dimethyl sulfoxide (DMSO). The moisture content of the solution is determined by the Karl Fischer (KF) method and adjusted to achieve a moisture content of 0.1% to 0.4%, typically 0.2%.

To initiate activation, prepare a fresh solution of 1,1'-carbonyl-di-1,2,4-triazole (CDT) or 1,1'-carbonyldiimidazole (CDI) at a concentration of 100 mg/ml in DMSO. The saccharide is activated with various amounts of CDT/CDI (1-10 molar equivalents) and the reaction is allowed to proceed for 1 hour at 23±2°C. The level of activation can be determined using HPLC. Cystamine dihydrochloride is prepared fresh in anhydrous DMSO at a concentration of 50 mg/ml. The activated saccharide is reacted with 1 molar equivalent (mole equivalent) of cystamine dihydrochloride.

Alternatively, the activated saccharide is reacted with 1 mol. equiv. cysteamine hydrochloride. The thiolation reaction is allowed to proceed for 21±2 hours at 23±2°C to give the thiolated saccharide. The level of thiolation is determined by additional CDT/CDI.

Residual CDT/CDI in the solution activation reaction is quenched by adding 100 mM sodium tetraborate, solution pH 9.0. Calculations are made to determine the additional amount of tetraborate and adjust the final moisture content to be up to 1-2% total water.

Recovery and purification of activated thiolated saccharide

The thiolated saccharide reaction mixture was diluted 10 times by addition to pre-chilled 5 mM sodium succinate in 0.9% saline, pH 6.0 and filtered through a 5 µm filter. Diafiltration of the thiolated saccharide is carried out against 40 times the diavolume of WFI. A solution of tri(2-carboxyethyl)phosphine (TCEP), 1-5 mol. eq., after diluting 10% by volume with 0.1 M sodium phosphate buffer, pH 6.0. This reduction reaction is allowed to proceed for 20±2 hours at 5±3°C. Purification of the activated thiolated saccharide is preferably carried out using ultrafiltration/diafiltration against pre-chilled 10 mM monobasic sodium phosphate, pH 4.3. Alternatively, the thiolated saccharide is purified using standard gel permeation chromatography (SEC) techniques or ion exchange chromatographic techniques. An aliquot of the activated thiolated saccharide rethenate is removed to determine the saccharide concentration and perform thiol assays (Elman).

Alternative Recovery and Purification of Activated Thiolated Saccharide

As an alternative to the purification procedure described above, the activated thiolated saccharide was also purified as described below.

To the reaction mixture of thiolated saccharide was added a solution of tri(2-carboxyethyl)phosphine (TCEP), 5-10 mol. eq., and allowed to proceed the reaction for 3±1 hours at 23±2°C. The reaction mixture was then diluted 5-fold by adding to pre-chilled 5 mM sodium succinate in 0.9% saline, pH 6.0 and filtered through a 5 µm filter. Diafiltration of the thiolated saccharide was performed using a 40-fold diavolume of pre-chilled 10 mM sodium phosphate monobasic solution, pH 4.3. An aliquot of the activated thiolated saccharide rethenate was withdrawn to determine the saccharide concentration and perform thiol assays (Elman).

Activation and purification of bromoacetylated carrier protein

The free amino groups of the carrier protein are bromoacetylated by reaction with a bromoacetylating agent such as bromoacetic acid N-hydroxysuccinimide ester (BAANS), bromoacetyl bromide, or other suitable reagent.

The carrier protein (in 0.1M sodium phosphate, pH 8.0±0.2) is first held at 8±3° C., at approximately pH 7, before activation. An N-hydroxysuccinimide bromoacetic acid ester (BAANS) was added to the protein solution as a stock solution in dimethyl sulfoxide (DMSO) (20 mg/mL) at a ratio of 0.25-0.5 BAANS:protein (w/w). The reaction is gently stirred at 5±3°C for 30-60 minutes. The resulting bromoacetylated (activated) protein is purified, for example, using ultrafiltration/diafiltration using a 10 kDa MWCO membrane with 10 mM phosphate (pH 7.0) buffer. After purification, the protein concentration of the bromoacetylated carrier protein was assessed according to the Lowry protein assay.

The degree of activation is determined by total bromide analysis using ion exchange liquid chromatography combined with conductometric detection with suppression of background electrical conductivity (ion chromatography). Bound bromide on the activated bromoacetylated protein is cleaved from the protein in the sample and quantitation preparation, along with any free bromide that may be present. Any remaining covalently bound bromine on the protein is released by conversion to the ionic bromide by heating the sample in alkaline 2-mercaptoethanol.

Activation and purification of bromoacetylated CRM ₁₉₇

CRM ₁₉₇ was diluted to 5 mg/ml with 10 mM phosphate buffer 0.9% NaCl pH 7 (PBS) and then prepared 0.1 M NaHCO ₃ , pH 7.0 using 1 M stock solution. BAANS was added to CRM ₁₉₇ : BAANS in a 1:0.35 (w:w) ratio using BAANS stock solution of 20 mg/mL DMSO. The reaction mixture was incubated at 3°C to 11°C for 30 minutes-1 hour, then purified using ultrafiltration/diafiltration using a 10K MWCO membrane and 10 mM sodium phosphate/0.9% NaCl, pH 7.0. Purified activated CRM ₁₉₇ was analyzed by Lowry assay to determine the protein concentration and then diluted with PBS to 5 mg/ml. Added sucrose to 5% wt./about. as a cryoprotectant and activated protein was frozen and stored at -25°C until necessary for conjugation.

Bromoacetylation of the lysine residues of CRM ₁₉₇ was very consistent, resulting in the activation of 15 to 25 lysines out of 39 available lysines. The reaction gave high yields of activated protein.

Conjugation of an activated thiolated saccharide with a bromoacetylated carrier protein

Before starting the conjugation reaction, the reaction vessels are pre-cooled to 5°C. The bromoacetylated carrier protein and the activated thiolated saccharide are sequentially added and mixed at a stirring speed of 150-200 rpm. The input ratio of saccharide/protein is 0.9±0.1. The pH of the reaction is adjusted to 8.0±0.1 with 1 M NaOH. The conjugation reactions are allowed to proceed at 5°C for 20±2 hours.

Blocking of residual reactive functional groups

Unreacted bromoacetylated residues on the carrier protein are quenched by interaction of 2 mol. equiv. N-acetyl-L-cysteine as blocking reagent for 3 hours at 5°C. Residual free sulfhydryl groups block 4 mol. equiv. iodoacetamide (IAA) for 20 hours at 5°C.

Purification of eTEC-linked glycoconjugate

The conjugation reaction mixture (post-IAA-blocked) is filtered through a 0.45 µm filter. Ultrafiltration/diafiltration of the glycoconjugate is carried out against 5 mM succinate-0.9% saline, pH 6.0. The glycoconjugate rethenate is filtered through a 0.2 µm filter. An aliquot of the glycoconjugate is withdrawn for analysis. The remaining glycoconjugate store three 5°C.

Example 2 Preparation of Pn-33F eTEC Conjugates

Activation process

Activation of Pn33F polysaccharide

Pn-33F polysaccharide was mixed with 500 mM 1,2,4-triazole (in WFI) to give 10 grams of triazole per gram of polysaccharide. The mixture was frozen in the shell in a dry ice-ethanol bath and then lyophilized to dryness. The lyophilized 33F polysaccharide was reconstituted in anhydrous dimethyl sulfoxide (DMSO). The moisture content of the freeze-dried 33F/DMSO solution was determined by the Karl Fischer (KF) method. The moisture content was adjusted by adding WFI to the 33F/DMSO solution to achieve a moisture content of 0.2%.

To initiate activation, fresh 1,1'-carbonyl-di-1,2,4-triazole (CDT) was prepared as a 100 mg/ml solution in DMSO. The Pn33F polysaccharide was activated with various amounts of CDT prior to the thiolation step. CDT activation was performed at 23±2°C for 1 hour. The level of activation was determined by HPLC (A220/A205). Sodium tetraborate solution, 100 mM, pH 9.0 was added to quench any residual CDT in the solution activation reaction. Calculations are made to determine the additional amount of tetraborate and allow a final moisture content of 1.2% total water. The reaction was allowed to proceed for 1 hour at 23±2°C.

Thiolation of activated Pn-33F polysaccharide

Cystamine dihydrochloride was prepared fresh in anhydrous DMSO, and 1 mol. equiv. cystamine dihydrochloride was added to the activated polysaccharide reaction solution. The reaction was allowed to proceed for 21±3 hours at 23±2°C. The thiolated saccharide solution was diluted 10 times by addition to pre-chilled 5 mM sodium succinate in 0.9% saline, pH 6.0. The diluted reaction solution was filtered through a 5 μm filter. Diafiltration of the thiolated Pn-33F polysaccharide was performed on 100K MWCO ultrafiltration membrane cassettes using water for injection (WFI).

Recovery and Purification of Activated Thiolated Pn-33F Polysaccharide

Tri(2-carboxyethyl)phosphine (TCEP), 5 mol. eq., after diluting 10% by volume with 0.1 M sodium phosphate buffer, pH 6.0. This reduction reaction was allowed to proceed for 2±1 hours at 23±2°C. Diafiltration of the thiolated 33F polysaccharide was performed on 100K MWCO ultrafiltration membrane cassettes. Diafiltration was carried out against pre-chilled 10 mm sodium phosphate, pH 4.3. The thiolated 33F polysaccharide rethenate was sampled for both saccharide and thiol concentration analysis (Elman).

Alternative Recovery and Purification of Activated Thiolated Pn-33F Polysaccharide

As an alternative to the purification procedure described above, the 33F activated thiolated saccharide was also purified as follows. To the reaction mixture of thiolated saccharide was added a solution of tri(2-carboxyethyl)phosphine (TCEP), 5 mol. eq., and allowed to proceed the reaction for 3±1 hours at 23±2°C. The reaction mixture was then diluted 5-fold by addition to pre-chilled 5 mM sodium succinate in 0.9% saline, pH 6.0 and filtered through a 5 µm filter. Diafiltration of the thiolated saccharide was performed using a 40-fold diavolume of pre-chilled 10 mM monobasic sodium phosphate, pH 4.3 on 100K MWCO ultrafiltration membrane cassettes. The thiolated 33F polysaccharide rethenate was sampled for both saccharide and thiol concentration analysis (Elman). A block diagram of the activation process is shown in Figure 8(A).

conjugation process

Conjugation of thiolated Pn33F polysaccharide with bromoacylated CRM ₁₉₇

The CRM ₁₉₇ carrier protein was activated separately by bromoacetylation as described in Example 1 and then reacted with an activated Pn-33F polysaccharide for a conjugation reaction. Before starting the conjugation reaction, the reaction vessel was pre-cooled to 5°C. The bromoacetylated CRM ₁₉₇ and the thiolated 33F polysaccharide were mixed together in a reaction vessel at a stirring speed of 150-200 rpm. The input saccharide/protein ratio was 0.9±0.1. The reaction pH was adjusted to 8.0-9.0. The conjugation reaction was allowed to proceed at 5°C for 20±2 hours.

Blocking of reactive groups on bromoacetylated CRM ₁₉₇ and thiolated Pn33F polysaccharide

Unreacted bromoacetylated residues on CRM ₁₉₇ proteins were blocked by interaction with 2 mol. equiv. N-acetyl-N-cysteine for 3 hours at 5°C, followed by blocking of any residual free sulfhydryl groups of the thiolated 33F-polysaccharide with 4 mol. equiv. iodoacetamide (IAA) for 20 hours at 5°C.

Purification of eTEC-linked Pn-33F glycoconjugate The conjugation solution was filtered through a 0.45 µm or 5 µm filter. Diafiltration of the 33F glycoconjugate was performed on 300K MWCO ultrafiltration membrane cassettes. Diafiltration was performed against 5 mM succinate-0.9% saline, pH 6.0. Rethenate Pn-33F glycoconjugate 300K was then filtered through a 0.22 μm filter and stored at 5°C. A flowchart of the conjugation process is shown in Figure 8(B).

results

Reaction parameters and characterization data for several batches of Pn-33F eTEC glycoconjugates are shown in Table 1. CDT activation-thiolation of cystamine with dihydrochloride generated glycoconjugates having 63% to 90% saccharide yields and <1% to 13% free saccharides.

OPA Titers of Pn-33F eTEC Glycoconjugates with CRM ₁₉₇

Pn-33F OPA titers in mice were determined under standard conditions (similar to the OPA methods described below for conjugates 10A and 22F). OPA titers (GMT with 95% CI) at four and seven weeks are shown in Table 2, demonstrating that the 33F Pn serotype glycoconjugate elicited OPA titers in a mouse immunogenicity model.

Example 3 Preparation of Additional Pn-33F eTEC Conjugates

Additional Pn-33F eTEC conjugates were prepared using the method described in Example 2. Reaction parameters and characterization data for these additional batches of Pn-33F eTEC glycoconjugates are shown in Table 3.

As shown above and in Table 3, several Pn-33F conjugates were made using the eTEC conjugation above. eTEC chemistry has allowed the preparation of conjugates with high yield, low % free saccharide and a high degree of conjugation (conjugated lysines). Additionally, it was possible to protect more than 80% of the acetyl functionality using the eTEC conjugation method.

Example 4 Stability Evaluation of Pn-33F eTEC Glycoconjugates: Trends in % Free Saccharide

Aliquots of the 33F-2B conjugate series (see Table 1) were dosed into polypropylene tubes and stored at 4°C, 25°C, and 37°C, respectively, and monitored for trends in % free saccharide. The data (% free saccharide) is shown in Table 4. As shown in this table, there was no significant change in % free saccharide.

Accelerated stability of another batch of conjugate (Lot 33F-3C) was also run at 37° C. up to 1 month. As shown in Table 5, there was no significant change in % free saccharide at 37° C. up to 1 month.

To further confirm the stability of the eTEC conjugates, additional series conjugates (33F-3C and 33F-5E (see Table 1)) were stored at 4° C. and monitored for approximately one year, for potential trends in % free saccharide. As shown in Table 6, there was no significant change in % free saccharide levels for conjugates stored at 4° C. for extended periods up to approximately one year.

Serotype 33F conjugates made using 33F eTEC chemistry were shown to be stable with no noticeable degradation as monitored by free saccharide trends at various temperatures (real time and fast).

Example 5 Preparation of Pn-8 CRM ₁₉₇ Conjugates

Obtaining Pp-8 RAC/DMSO glycoconjugates

The frozen polysaccharide was thawed and transferred to a reaction vessel. 2 M acetic acid and WFI (water for injection) were added to the polysaccharide solution to achieve a final polysaccharide concentration of approximately 2.5 g/l and a final acetic acid concentration of 0.2 M.

Hydrolysis of a polysaccharide

The native polysaccharide was chemically hydrolyzed prior to activation. The diluted polysaccharide solution was heated to 70° C. and then held at that temperature for 3.5 hours.

Polysaccharide oxidation

The oxidation of the polysaccharide was initiated by adding sodium periodate solution, and the reaction was left to proceed for 20 hours at 23°C.

Purification of activated polysaccharide

The activated polysaccharide was concentrated using ultrafiltration cassettes. Diafiltration was performed against a 20-fold dipovolume of WFI.

Lyophilization

The activated polysaccharide is mixed with sucrose in a ratio of 25 grams of sucrose per gram of activated polysaccharide. Vials containing activated saccharide and sucrose are frozen in the shell in ethanol baths and lyophilized.

Conjugation of activated polysaccharide with CRM ₁₉₇ and blocking

The lyophilized activated polysaccharide was reconstituted to 2 mg/ml in DMSO. DMSO was added to the lyophilized CRM ₁₉₇ for reconstitution. The restored CRM _{197 was} added to the restored activated polysaccharide. Then initiated the conjugation by adding sodium cyanoborohydride to the reaction mixture and incubated at 23°C for 24 hours. Termination of the conjugation reaction is carried out by adding 2 meq of sodium borohydride. This blocking of the reaction was carried out for 3 hours at 23°C.

Purification of the conjugate

The conjugate solution was then diluted with chilled 5 mM succinate-0.9% saline (pH 6.0), filtered, concentrated to 2-4 g/L using 300K cellulose membranes, and the first diafiltration step was performed against 5 mM succinate-0. 9% saline solution (pH 6.0). The final purification step was performed by diafiltration with 5 mM succinate-0.9% saline, pH 6.0 buffer. After diafiltration was completed, the purified conjugate was transferred to a collection vessel through a 0.22 μm filter.

Dilution of monovalent bulk conjugate

The conjugate was diluted with additional 5 mM succinate/0.9% saline (pH 6) to a target saccharide concentration of 0.5 mg/mL. A final 0.22 µm filtration step was completed to provide a monovalent bulk conjugate product (MBC) for the formulation.

Several conjugates were prepared using the method described above by varying various parameters (eg, saccharide-protein input ratio, reaction mixture concentration, and meq of sodium cyanoborohydride). Characterization of the presented Pn-8 glycoconjugates with CRM ₁₉₇ is given in Table 7.

Opsonophagocytic activity (OPA) titers for the serotype 8-CRM ₁₉₇ conjugates in mice were determined in mice under standard conditions (similar to the OPA methods described below for the 10A and 22F conjugates). OPA titers (geometric mean titer (GMT) with 95% confidence interval (CI)) after four weeks at various doses are shown in Tables 8 and 9 (two separate experiments), demonstrating that the serotype 8 conjugate (samples 1-9; also see Table 7 for characterization data of these conjugates) elicited OPA titers in a mouse immunogenicity model.

As shown in Table 8, the serotype 8 conjugates were shown to have significantly higher antibody titers compared to the control unconjugated polysaccharide, which gave low antibody titers.

The overall data obtained from conjugates prepared by the reductive amination process described above demonstrated that this allowed the preparation of conjugates with good conjugation yield, low % free saccharide and good stability. Additionally, the resulting conjugates produced good OPA titers in a mouse immunogenicity model.

Example 6 Preparation of a serotype 10A-CRM ₁₉₇ polysaccharide conjugate

Preparation of Isolated S. pneumoniae Serotype 10A Polysaccharide Serotype 10A capsular polysaccharides can be obtained directly from bacteria using isolation procedures known to those skilled in the art (see, for example, methods disclosed in US Patent Application Publication Nos. 2006/0228380, 2006/ 0228381, 2007/0184071, 2007/0184072, 2007/0231340 to 2008/0102498 and WO 2008/118752). Streptococcus pneumoniae serotype 10A was grown in a seed flask and then transferred to a seed fermenter. After the target optical density was reached, the cells were transferred to the production fermenter. The fermentation broth was inactivated by the addition of N-lauroylsarcosine and purified using ultrafiltration and diafiltration.

Oxidation of isolated capsular polysaccharide Streptococcus pneumoniae serotype 10A

A calculated volume of 0.1 M potassium phosphate buffer (pH 6.0) and water for injection (WFI) was added to the polysaccharide solution to achieve a final polysaccharide concentration of 2.5 g/L and a final concentration of 25 mM potassium phosphate buffer if necessary, adjust the pH to about 6.0. The diluted polysaccharide was then cooled to 5°C. The oxidation was initiated by adding a solution of 0.25 molar equivalents (M-eq.) sodium periodate. The oxidation reaction time was approximately 4 hours at 5°C. The oxidative reaction was quenched with 1 M-eq. 2,3-butanediol by continuing stirring at 5°C for 1-2 hours.

After reaching the target reaction time, the activated polysaccharide was concentrated using a 30k MWCO Millipore ultrafiltration cassette. Then diafiltration was performed against 20 times the WFI diavolume. The purified activated polysaccharide was stored at 5°C. The purified activated saccharide is characterized, inter alia, by (i) SEC-MALLS molecular weight and (ii) oxidation state.

Conjugation of activated S. pneumoniae serotype 10A polysaccharide with CRM ₁₉₇

The conjugation process included the following steps:

a. Mixing with sucrose excipient, and lyophilization;

b. Recovery of lyophilized polysaccharide and CRM ₁₉₇ ;

c. Conjugation of the activated polysaccharide with CRM ₁₉₇ and blocking; and

d. Conjugate Purification

a. Mixing with sucrose

The activated polysaccharide is mixed with sucrose in a ratio of 25 g of sucrose per gram of activated polysaccharide. The vial of the compounded mixture was then lyophilized. After lyophilization, the vials containing the lyophilized activated polysaccharide were stored at -20°C.

b. Recovery of lyophilized activated polysaccharide and CRM ₁₉₇ protein

The lyophilized activated polysaccharide was reconstituted in anhydrous dimethyl sulfoxide (DMSO). After complete dissolution of the polysaccharide, the same amount of DMSO was added to the calculated CRM ₁₉₇ for recovery.

c. Conjugation of activated polysaccharide with CRM ₁₉₇ and blocking

The reduced CRM ₁₉₇ (in DMSO) was added to the reduced activated polysaccharide in the conjugation reactor. The final concentration of the polysaccharide is 1 g/L. Conjugation was carried out by adding 1.2 M-eq. sodium cyanoborohydride to the reaction mixture. The reaction was incubated at 23°C for 24 hours. Completion of the conjugation reaction was carried out by adding 2 M-eq. sodium borohydride. The blocking reaction was incubated at 23°C for 3 hours.

Completion of the conjugation reaction was carried out by adding 2 M-eq. sodium borohydride. This blocking reaction was run for 3 hours at 23°C.

d. Purification of the conjugate

The conjugate solution was then diluted 5x (v/v) with chilled 5mM succinate-0.9% saline (pH 6.0) and 20x diafiltration was performed using 5mM succinate-0.9% saline (pH 6.0). After the initial diafiltration was complete, the conjugate rethenate was transferred through a 0.22 µm filter. The conjugate was diluted with additional 5 mM succinate/0.9% saline (pH 6) and after a final 0.22 µm filtration step, it was stored at 2-8°C.

Several conjugates were prepared using the method described above by varying various parameters (eg, saccharide-protein input ratio, reaction mixture concentration, and M-eq. sodium cyanoborohydride). The above chemistry produced serotype 10A conjugates that were shown to be stable with no noticeable degradation monitored by free saccharide trends at various temperatures (real time and fast). The characteristics of the presented Pn-10A glycoconjugates with CRM ₁₉₇ are shown in Table 10.

Opsonophagocytic activity (OPA) titers for serotype 10A-CRM ₁₉₇ conjugates in mice were determined under standard conditions. Groups of thirty 6-7 week old female Swiss Webster mice were immunized with 0.001 μg, 0.01 μg, or 0.1 μg of the test conjugates by subcutaneous injection at 0 weeks of age. Mice were boosted with the same dose of conjugate at 3 weeks of age and then bled at 4 weeks of age. Serotype-specific ORAs were performed on 4 week old sera samples.

Opsonophagocytic activity assays (OPAs) are used to measure functional antibodies in mouse sera specific for S. pneumoniae serotype 10A. The serum test is established in assay reactions that measure the ability of the specific immunoglobulin capsular polysaccharide to opsonize bacteria, trigger complement deposition, thereby facilitating phagocytosis and killing bacteria by phagocytes. The OPA titer is defined as the reciprocal dilution that results in a 50% reduction in bacteria compared to control wells without test serum. The OPA titer is interpolated from two dilutions that cover a given 50% kill cutoff.

OPA procedures were based on the methods described in Hu et al. (2005) Clin Diagn Lab Immunol12 (2): 287-295 with the following modifications. The test serum was serially diluted 2.5-fold and added to microtiter plates for analysis. Live target bacterial strains of serotype 10A were added to the wells and the plates were shaken at 37°C for 30 minutes. Differentiated HL-60 cells (phagocytes) and baby rabbit serum (3-4 weeks old, PEL-FREES®, 12.5% final concentration) were added to the wells and the plates were shaken at 37° C. for 60 minutes. To terminate the reaction, 80 μl of 0.9% NaCl was added to all wells, mixed, and a 10 μl aliquot was transferred to the wells of MULTISCREEN® HTS HV filter plates (MILLIPORE®) containing 200 μl of water. The liquid was filtered through the plates under vacuum and 150 μl of HYSOY® medium was added to each well and filtered. The filter plates were then incubated at 37° C., 5% CO ₂ overnight and then fixed with a bleach solution (Bio-Rad Laboratories, Inc., Hercules, CA). The plates were then stained with Coomassie blue and decolorized once. Colonies were examined and listed using the Cellular Technology Limited (CTL) (Shaker Heights, OH) IMMUNOSPOT® Analyzer. Raw colony counts were used to plot kill curves and calculate OPA titers. OPA titers (geometric mean titer (GMT) with 95% confidence interval (CI)) after four weeks at various doses are shown in Table 11, demonstrating that the serotype 10A conjugate (Samples 1-3; also see Table 10 for characterization data of these conjugates ) elicited OPA titers in a mouse immunogenicity model. As shown in Table 11, serotype 10A conjugates were shown to have significantly higher OPA titers compared to the control unconjugated polysaccharide, which had a low OPA response.

Example 7 Conjugation of Pn cepotype-12F using TEMPO/NCS

In order to improve the stability of 12F-CRM ₁₉₇ serotype glycoconjugates, alternative biochemistries have been investigated using 2,2,6,6-tetramethyl-1-piperidinyloxy free radical (TEMPO) and N-chlorosuccinimide (NCS) as a co-oxidant for the oxidation of primary alcohols. to aldehyde groups. GC/MS analysis showed that the sites were oxidized differently for periodate-mediated oxidation. In the case of TEMPO-NCS oxidation, α-D-Glcp and 2-Glcp were oxidized, while α-D-Galp was the main site of oxidation when periodate was used (see Figure 4). As described in more detail hereinafter, TEMPO was used in catalytic amounts (≥0.1 molar equivalent) and the desired oxidation state (DO) was achieved by varying the amounts of NCS used. Subsequently, several conjugates have been synthesized and characterized. In general, the preparation of serotype 12F glycoconjugates was carried out in several stages, as follows:

a) Hydrolysis of serotype 12F polysaccharide to molecular weights from 50 kDa to 500 kDa

b) TEMPO/NCS serotype 12F polysaccharide activation;

c) Purification of the activated polysaccharide;

d) Conjugation of activated serotype 12F with CRM ₁₉₇ protein; and

e) Purification of serotype 12F-CRM ₁₉₇ conjugates.

Hydrolysis and oxidation of serotype 12F

The hydrolysis of the polysaccharide was typically carried out under acidic conditions with heating, resulting in an average molecular weight in the desired range of 100 kDa to 350 kDa. A typical experiment is described below.

Hydrolysis

The serotype 12F polysaccharide solution was added to the jacketed reaction vessel. To this, the required volume of 0.30 M acetic acid and water for injection (WFI) was added, maintaining a concentration of ~0.1 M acetic acid. The pH of the solution was adjusted to 3.2±0.3 using 1N NaOH or glacial acetic acid. The temperature of the reaction mixture was raised to 70±5°C. The reaction mixture was stirred at 70±5°C for 90-120 minutes. The reaction mixture was cooled to 23±2°C and neutralized (pH 7.0) by adding 1 M NaOH solution. The hydrolyzed polysaccharide was purified using anti-WFI ultrafiltration/diafiltration using 30K MWCO membranes. The solution was filtered through a 0.22 μm filter and stored at 2-8° C. until oxidized. The molecular weight of the hydrolyzed polysaccharide was analyzed by SEC-MALLS to ensure that the molecular weight was within the target range of 100 kDa to 350 kDa.

Partial oxidation

In one experiment, serotype 12F polysaccharide was mechanically sized using pressure homogenization using a microfluidizer to reduce the molecular weight to about 100 kDa to 500 kDa. Sorted polysaccharide was added to the reaction vessel at a concentration of 4.0 mg/ml and mixed with bicarbonate/carbonate buffer (0.5 M NaHCO ₃ /0.05 M Na ₂ CO ₃ buffer, pH 8.6) in a ratio of 1:1 vol./rev. ≤0.1 mole equivalent of TEMPO was added to the stirred mixture. The reaction was started by adding 0.6 to 1.0 mole equivalent of NCS. The reaction mixture was stirred at room temperature for 2 hours, after which the activated polysaccharide was purified by diafiltration, with WFI using a 30K ultrafiltration membrane. The purified polysaccharide was collected and the oxidation state (DO) was determined by quantitative measurements of aldehyde (using 3-methyl-2-benzothiazolinone (MBTH) hydrazone assay) and polysaccharide (using anthrone assay).

In another experiment, a serotype 12F polysaccharide was hydrolyzed to reduce the molecular weight to a molecular weight of about 100 kDa to 500 kDa. The serotype 12F polysaccharide was added to the reaction vessel and mixed with 0.5 M NaHCO ₃ /0.05 M Na ₂ CO ₃ buffer (pH 8.6) at a ratio of 1:1 v/v. To the stirred mixture was added 0.6 to 1.0 molar equivalent of NCS dissolved in WFI. Activation was initiated by adding approximately 0.1 molar equivalent of TEMPO dissolved in WFI. The reaction mixture was stirred at room temperature for 2 hours, after which the activated polysaccharide was purified using WFI diafiltration using a 30K ultrafiltration membrane. The purified activated polysaccharide was filtered through a 0.2 μm filter and stored at 4°C until use.

TEMPO/NCS mediated oxidations have also been successfully performed in sodium phosphate buffers pH 6.5, 7.0, 7.5 and 8.0. In some activation experiments, a primary alcohol such as n-propanol was used to quench the reactants in order to avoid oxidation of the saccharide. In another set of experiments, the chemically hydrolyzed polysaccharide was oxidized directly, without the ultrafiltration/diafiltration purification step.

Conjugation of oxidized polysaccharide serotype 12F

In one experiment, purified oxidized serotype 12F polysaccharide was added to a reaction vessel followed by the addition of 0.5 M sodium phosphate buffer (pH 6.5) to a final buffer concentration of 0.1 M. To this solution, previously lyophilized CRM ₁₉₇ was added and thoroughly mixed in order to obtain a homogeneous solution. The pH was adjusted to 6.8 using dilute HCl or 1N NaOH solution. Then 1.5 molar equivalents of NaCNBH ₃ were added. The reaction mixture was stirred for 24 hours at room temperature (23°C) and for 2.5 days at 37°C. The reaction mixture was then diluted 1X with 0.9% saline and unreacted aldehyde groups were "capped" with 2 molar equivalents of sodium borohydride. The blocking reaction time was 3 hours.

In another experiment, purified activated serotype 12F was added to a reaction vessel followed by 0.5 M sodium phosphate buffer (pH 6.5) to a final buffer concentration of 0.1 M. To this solution was added and vigorously mixed previously lyophilized CRM ₁₉₇ to get a homogeneous solution. The pH was adjusted to 6.8 using dilute HCl or 1N NaOH solution. Then 3 molar equivalents of NaCNBH3 were added. The reaction mixture was stirred for 24 hours at 23°C and for 48 hours at 37°C. The reaction mixture was then diluted 1X with 0.9% brine and with stirring, unreacted aldehyde groups were "blocked" with 1 molar equivalent of sodium borohydride NaBH ₄ . The blocking reaction time was 3 hours.

In another experiment, purified activated serotype 12F was added to the reaction vessel and mixed with the CRM ₁₉₇ solution. The mixture was lyophilized and the powder was dissolved in 0.1 M sodium phosphate buffer (pH 6.8) to a final saccharide concentration of 5 mg/ml. If necessary, the pH was adjusted to 6.8 using dilute HCl or 1N NaOH solution. Then 3 molar equivalents of NaCNBH ₃ were added. The reaction mixture was stirred for 24 hours at 23°C and for 48 hours at 37°C. The reaction mixture was then diluted 1X with 0.9% brine, unreacted aldehyde groups were "blocked" with 1 molar equivalent of sodium borohydride NaBH ₄ . The blocking reaction time was 3 hours.

Purification of the conjugate

The blocked reaction mixture was filtered using a 5 µm filter and then purified using 100K MWCO ultrafiltration membranes. The conjugate was first diafiltered using 10 mM succinate/0.9% saline, pH 6.0 buffer. The purified conjugate was then filtered through 0.45/0.22 µm filters to obtain a bulk conjugate.

Oxidation state

Successful oxidation of the primary alcohol in the serotype 12F polysaccharide was achieved using the TEMPO/NCS system. Hydrolyzed serotype 12F polysaccharides were oxidized to various oxidation state (DO) levels by adjusting the amount of NCS co-oxidant. The effect on DO by varying the amounts of NCS using different polysaccharide lots and molecular weights is shown in Figure 9. Typically, the oxidation reaction is complete in 2 hours, as no significant change in DO was observed after 2 hours.

Several 12F serotype conjugates were prepared and characterized using TEMPO/NCS of the oxidized polysaccharide. The results are summarized in table 12.

Example 8 Immunogenicity of Pn Serotype 12F-CRM ₁₉₇ Conjugates Using the TEMPO/NCS Oxidation Method

Opsonophagocytic activity (OPA) titers for serotype 12F-CRM ₁₉₇ conjugates in mice were determined in mice under standard conditions. OPA titres (geometric mean titer (GMT) with 95% confidence interval (CI)) at four and seven weeks are shown in Table 13, demonstrating that the 12F-CRM ₁₉₇ serotype conjugate (Lot 12F-97B; also see Table 12 for characterization data of this conjugate) elicited OPA titers in a mouse immunogenicity model. The TEMPO-NCS conjugate was more immunogenic than the control conjugate (171 B) prepared by periodate oxidation.

Example 9 Stability Evaluation of Pn-12F Glycoconjugates

Comparison of the stability (at 25°C) of the conjugates obtained by periodate oxidation versus TEMPO/NCS oxidation (see Figure 10) demonstrated that the conjugates obtained by oxidation of Pn-12F polysaccharides were relatively more stable. As shown in Figure 10, an increase in free saccharide over time was observed for the glycoconjugate obtained by Pn-12F periodate oxidation of the polysaccharide at 25°C. In contrast, the glycoconjugate prepared by TEMPO/NCS oxidation of Pn-12F polysaccharide showed little trend for free saccharide under similar conditions.

Example 10. Obtaining a polysaccharide conjugate serotype 15B - CRM ₁₉₇

Obtaining an isolated polysaccharide of Streptococcus pneumoniae serotype 15B

Serotype 15B capsular polysaccharides can be obtained directly from bacteria using isolation procedures known to those skilled in the art. S. pneumoniae serotype 15B was grown in a seed flask and then transferred to a seed fermenter. After the target optical density was reached, the cells were transferred to the production fermenter. The fermentation broth was inactivated by the addition of N-lauroylsarcosine and purified using ultrafiltration and diafiltration.

The purified S. pneumoniae serotype 15B polysaccharide was then size-sorted by high pressure homogenization using a PANDA 2K® homogenizer (GEA Niro Soavi, Parma, Italy) to obtain an isolated S. pneumoniae serotype 15B polysaccharide.

Preferably, the isolated S. pneumoniae serotype 15B capsular polysaccharide obtained according to the method above contains at least 0.6 mM acetate per mM serotype 15B capsular polysaccharide and has a molecular weight of 50 kDa to 500 kDa, preferably 150 kDa to 350 kDa.

Oxidation of isolated capsular polysaccharide Streptococcus pneumoniae serotype 15B

The oxidation of the polysaccharide was carried out in 100 mM potassium phosphate buffer (pH 6.0) by sequentially adding the calculated amount of 500 mM potassium phosphate buffer (pH 6.0) and WFI, obtaining a final polysaccharide concentration of 2.0 g/l. If necessary, the pH of the reaction was adjusted to a pH of approximately 6.0. After adjusting the pH, the reaction temperature was adjusted to 23°C. The oxidation was initiated by adding approximately 0.25 molar equivalents of sodium periodate. The oxidation reaction was carried out at 23°C for approximately 16 hours.

Concentration and diafiltration of the activated polysaccharide was performed using 10K MWCO ultrafiltration cassettes. Diafiltration was performed against 20-fold WFI diavolumes. The purified activated polysaccharide was then stored at 5°C. The purified activated saccharide was characterized inter alia by (i) saccharide concentration by calorimetric analysis; (ii) aldehyde concentration by calorimetric analysis; (iii) oxidation state; (iv) SEC-MALLS molecular weight; and (v) the presence of O-acetyl and glycerol.

SEC-MALLS are used to determine the molecular weight of polysaccharides and polysaccharide-protein conjugates. SEC is used to separate polysaccharides by hydrodynamic volume. Refractive index (RI) and polygonal laser light scattering (MALLS) detectors are used to determine molecular weight. When light interacts with matter, it scatters, and the amount of scattered light is related to concentration, the square of dn/dc (specific refractive index increments), and the molar mass of the substance. The molecular weight measurement is calculated from the MALLS detector's scattered light readings and the detector's RI signal concentration.

The oxidation state (DO = moles of sugar repeating unit/moles of aldehyde) of the activated polysaccharide was determined as follows: The moles of sugar repeating unit are determined using various colorimetric methods, for example by using the anthrone method. The polysaccharide is first broken down into monosaccharides by the action of sulfuric acid and heat. The anthrone reagent reacts with hexose to form a yellow-green complex whose absorption is read spectrophotometrically at 625 nm. Within the assay range, absorbance is directly proportional to the amount of hexose present.

Moles of aldehyde are also determined simultaneously using the MBTH colorimetric method. MBTH analysis involves the formation of an azine compound by reacting aldehyde groups (provided sample) with 3-methyl-2-benzothiozolone hydrazone (MBTH reagent analysis). An excess of 3-methyl-2-benzothiozolone hydrazone is oxidized to form a reactive cation. The reactive cation and azine react to form the blue chromophore. The formed chromophore is read spectroscopically at 650 nm.

Preferably, the activated S. pneumoniae serotype 15B capsular polysaccharide prepared according to the method above contains at least 0.6 mM acetate per mM serotype 15B capsular polysaccharide and has a molecular weight of 50 kDa to 500 kDa, preferably 150 kDa to 350 kDa.

Conjugation of activated capsular polysaccharide S. pneumoniae serotype 15B with CRM ₁₉₇

The conjugation process includes the following steps:

a) Mixing with sucrose excipient and lyophilization;

b) Recovery of lyophilized activated polysaccharide and CRM ₁₉₇ ;

c) Conjugation of the activated polysaccharide with CRM ₁₉₇ and blocking; and

d) Purification of the conjugate

a) Mixing with sucrose excipient and lyophilization

The activated polysaccharide was mixed with sucrose at a ratio of 25 grams of sucrose per gram of activated polysaccharide. The vial of the compounded mixture was then lyophilized. After lyophilization, the vials containing the lyophilized activated polysaccharide were stored at -20°C. The calculated amount of CRM ₁₉₇ protein was frozen in the shell and lyophilized separately. Lyophilized CRM ₁₉₇ was stored at -20°C.

b) Recovery of lyophilized activated polysaccharide and CRM ₁₉₇ protein

The lyophilized activated polysaccharide was reconstituted in anhydrous dimethyl sulfoxide (DMSO). After complete dissolution of the polysaccharide, the same amount of anhydrous DMSO was added to the lyophilized CRM ₁₉₇ for reconstitution.

c) Conjugation and blocking

The reduced activated polysaccharide was mixed with the reduced CRM ₁₉₇ in the reaction vessel (input ratio: 0.8:1), followed by thorough mixing to obtain a clear solution before conjugation with sodium cyanoborohydride. The final concentration of the polysaccharide in the reaction solution is approximately 1 g/l. Conjugation was initiated by adding 1.0-1.5 M-eq. sodium cyanoborohydride into the reaction mixture and incubated at 23°C for 40-48 hours. The conjugation reactions were completed by adding 2 M-eq. sodium borohydride (NaBH ₄ ) in order to block unreacted aldehydes. This blocking reaction was continued at 23° C. for 3 hours.

d) Purification of the conjugate

The conjugate solution was diluted 1:10 with chilled 5 mM succinate-0.9% saline (pH 6.0) in preparation for purification by tangential flow filtration using 100-300K MWCO membranes. The diluted conjugate solution was passed through a 5 μm filter and diafiltration was performed using 5 mM succinate-0.9% saline (pH 6.0) as medium. After diafiltration was complete, the conjugate rethenate was transferred through a 0.22 µm filter.

The conjugate was further diluted with 5 mM succinate/0.9% saline (pH 6) to a target saccharide concentration of approximately 0.5 mg/mL. The final filtration step through 0.22 μm was completed to obtain the glycoconjugate. Preferably, the conjugate prepared according to the method above contains at least 0.6 mM acetate per mM serotype 15B capsular polysaccharide, has a molecular weight of 3,000 kDa to 20,000 kDa, and has a degree of conjugation of 2 to 6.

Example 11 Characterization of the glycoconjugate. containing capsular polysaccharide S. pneumoniae serotype 15B covalently linked to CRM ₁₉₇

Conjugate 1 was obtained according to the method of example 10. Conjugates 2 and 3 were obtained according to a similar method using different amounts of oxidizing agent. Conjugate 4 was obtained according to a similar method, except that the purified serotype 15B capsular polysaccharide was not sorted by size and activated to a lower DO (higher oxidation states) and the conjugation was carried out in an aqueous medium. Conjugate 5 was obtained according to a similar method, except that the purified capsular polysaccharide serotype 15B was sorted by size by chemical hydrolysis, and the conjugation was carried out in an aqueous medium. Conjugates 6 and 7 were prepared according to a similar method, except that the purified serotype 15B capsular polysaccharide was not sized.

The resulting conjugates were characterized and the results are summarized in Table 14.

The percentage of free polysaccharide was measured using a protein-binding aluminum hydroxide gel technique, and the covalently bound saccharide was removed by centrifugation. Samples are mixed with phosphate buffered aluminum hydroxide gel and centrifuged. The bound saccharide is pelletized with the gel and the free saccharide remains in the supernatant. The resulting supernatant and controls are quantified by appropriate colorimetric assays to determine the percentage of free saccharide and confirm sufficient protein removal and saccharide recovery.

For amino acid analysis, a polysaccharide-protein sample is first hydrolyzed as free amino acids using 6N hydrochloric acid (HCl) hydrolysis under vacuum and heat (160° C. for 15 minutes). After hydrolysis, the samples are analyzed using an amino acid analyzer. Individual amino acids are separated by ion exchange chromatography using a stepwise gradient of sodium citrate buffer with changes in temperature and flow rate. After separation, the residual amount of each amino acid was quantified using a post-column ninhydrin coupling detection system. In this system, ninhydrin is mixed with the column eluate in a post-column reactor system and the mixture is sent to the photometer. The reaction of ninhydrin with the eluted amino acids gives a purple compound with an absorption maximum at 570 nm. This absorption is a linear response (function) of the number of α-amino groups present, and this reaction provides a quantitative colorimetric analysis for all organic compounds with α-amino groups. In reaction with imino acids such as proline and hydroxylproline, which lack a free amino group, a bright yellow compound is formed and is monitored at 440 nm. Peak areas for each amino acid are calculated using the wavelength yields at both 570 nm and 440 nm.

The yield is calculated as follows: (amount of polysaccharide in conjugate × 100) / amount of activated polysaccharide.

Conjugates (4 to 5) prepared using an aqueous medium showed a significant loss of O-acetyl levels. Conjugates obtained in DMSO solvent using native polysaccharide without size sorting М.М. (6 and 7) showed no loss of O-acetyl levels. However, the yields of the conjugates were very low, and the filterability characteristics were also low. Conjugates made in DMSO using polysaccharides that were size-sorted by high pressure homogenization (1, 2 and 3) had high yield and better filterability characteristics with significant retention of O-acetyl levels. These conjugates also had very low levels of free polysaccharides.

Example 12 Opsonophagocytic activity (OPA) assay using Pn-serotype 15B-CRM ₁₉₇ conjugates

The immunogenicity of the S. pneumoniae serotype 15B conjugates of the invention can be assessed using the OPA assay described below.

Groups of 30 6-7 week old female Swiss Webster mice were immunized with 0.001 μg, 0.01 μg, or 0.1 μg of the test conjugates via subcutaneous administration at 0 weeks of age. Mice were boosted with the same dose of conjugate at 3 weeks of age and then bled at 4 weeks of age. Serotype-specific ORAs were performed on 4 week old sera samples.

OPAs are used to measure functional antibodies in mouse sera specific for S. pneumoniae serotype 15B. The studied serum was introduced into test reactions that measure the ability of the capsular polysaccharide of a specific immunoglobulin to opsonize a bacterium, deposition a trigger complement, thereby facilitating phagocytosis and destroying bacteria with the help of phagocytes. The OPA titer is defined as the reciprocal dilution that results in a 50% reduction in bacteria compared to control wells without test serum. The OPA titer is interpolated from two dilutions that cover a given 50% kill cutoff.

OPA procedures were based on the methods described in Hu et al. (2005) Clin Diagn Lab Immunol12 (2): 287-295 with the following modifications. The test serum was serially diluted 2.5-fold and added to microtiter plates for analysis. Live target bacterial strains of serotype 10A and 15B target bacteria were added to the wells and the plates were shaken at 37° C. for 30 minutes. Differentiated HL-60 cells (phagocytes) and baby rabbit serum (3-4 weeks old, PEL-FREES®, 6.25% final concentration) were added to the wells and the plates were shaken at 37° C. for 45 minutes. To terminate the reaction, 80 μl of 0.9% NaCl was added to all wells, mixed, and a 10 μl aliquot was transferred to the wells of MULTISCREEN® HTS HV filter plates (MILLIPORE®) containing 200 μl of water. The liquid was filtered with the plates under vacuum and 150 μl of HYSOY® medium was added to each well and filtered again. The filter plates were then incubated at 37° C., 5% CO ₂ overnight and then fixed with a bleach solution (Bio-Rad Laboratories, Inc., Hercules, CA). The plates were then stained with Coomassie blue and decolorized once. Colonies were examined and listed using the Cellular Technology Limited (CTL) (Shaker Heights, OH) IMMUNOSPOT® analyzer. Raw colony counts were used to plot kill curves and calculate OPA titers.

The immunogenicity of conjugates 1 and 2 was investigated in accordance with the above analysis. One additional conjugate and unconjugated native S. pneumoniae serotype 15B capsular polysaccharide (unconjugated PS) were also tested in the same assay:

Conjugate 9 was prepared by conjugating native (ie, not sized) serotype 15B capsular polysaccharide to CRM ₁₉₇ via reductive amination in aqueous solution.

The results are shown in Table 15.

As shown in Table 15 above, conjugates 1 and 2, when administered to mice, generated antibodies capable of opsonizing S. pneumoniae serotype 15B, deposition of trigger complement, thereby facilitating phagocytosis and killing bacteria by phagocytes. In addition, despite their lower molecular weight, they also showed a similar level of immunogenicity compared to conjugate 9, which was not sized.

Example 13. Obtaining a conjugate polysaccharide serotype 22F - CRM ₁₉₇

Preparation of S. pneumoniae serotype 22F isolated polysaccharide S. pneumoniae serotype 22F was grown in a seed flask and then transferred to a seed fermenter. After the target optical density was reached, the cells were transferred to the production fermenter. The fermentation broth was inactivated by the addition of N-lauroylsarcosine and purified using ultrafiltration and diafiltration.

The purified S. pneumoniae serotype 22F polysaccharide was size-sorted by high pressure homogenization using a PANDA 2K® homogenizer (GEA Niro Soavi, Parma, Italy) to obtain an isolated S. pneumoniae serotype 22F polysaccharide.

Oxidation of the isolated capsular polysaccharide of S. pneumoniae serotype 22F.

The oxidation of the polysaccharide was carried out in 100 mM potassium phosphate buffer (pH 5.8) prepared by successively adding the calculated amount of 500 mM potassium phosphate buffer (pH 5.8) and WFI to give a final polysaccharide concentration of 2.0 g/l. If necessary, the reaction pH was adjusted to about 5.8. After adjusting the pH, the reaction temperature was lowered to 5°C. The oxidation was initiated by adding 0.10 molar equivalent (M-equiv.) sodium periodate. The target oxidation reaction time is 16 hours at 5°C.

The oxidative reaction was quenched with 2 M-eq. 2,3-butanediol with continued stirring at 5°C for 1-2 hours.

Concentration and diafiltration of the activated polysaccharide was performed using 100K MWCO ultrafiltration cassettes. Diafiltration was performed against 35 times the diavolume of WFI. The purified activated polysaccharide was stored at 5°C. The purified activated saccharide was characterized inter alia by (i) molecular weight according to SEC-MALLS, (ii) presence of O-acetyl, and (iii) oxidation state.

SEC-MALLS are used to determine the molecular weight of polysaccharides and polysaccharide-protein conjugates. SEC is used to separate polysaccharides by hydrodynamic volume. Refractive index (RI) and polygonal laser light scattering (MALLS) detectors are used to determine molecular weight. When light interacts with matter, it scatters, and the amount of scattered light is related to concentration, the square of dn/dc (specific refractive index increments), and the molar mass of the substance. The molecular weight measurement is calculated from the MALLS detector's scattered light readings and the detector's RI signal concentration.

The oxidation state (DO = moles of sugar repeating unit / moles of aldehyde) of the activated polysaccharide was determined as follows:

Moles of sugar repeating unit are determined using various colorimetric methods, for example by using the anthrone method. The polysaccharide is first broken down into monosaccharides by the action of sulfuric acid and heat. The anthrone reagent reacts with hexose to form a yellow-green complex whose absorption is read spectrophotometrically at 625 nm. Within the assay range, absorbance is directly proportional to the amount of hexose present.

Moles of aldehyde are also determined simultaneously using the MBTH colorimetric method. MBTH analysis involves the formation of an azine compound by reacting aldehyde groups (provided sample) with 3-methyl-2-benzothiozolone hydrazone (MBTH reagent analysis). An excess of 3-methyl-2-benzothiozolone hydrazone is oxidized to form a reactive cation. The reactive cation and azine react to form the blue chromophore. The formed chromophore is read spectroscopically at 650 nm.

Conjugation of activated S. pneumoniae serotype 22F polysaccharide with CRM ₁₉₇

The conjugation process included the following steps:

a. Mixing with sucrose excipient, and lyophilization;

b. Recovery of lyophilized polysaccharide and CRM ₁₉₇ ;

c. Conjugation of the activated polysaccharide with CRM ₁₉₇ and blocking; and

d. Conjugate Purification

a. Mixing with sucrose and lyophilization

The activated polysaccharide was mixed with sucrose (50% w/v in WFI) at a ratio of 25 grams of sucrose per gram of activated polysaccharide. The vial of the compounded mixture was then lyophilized. After lyophilization, the vials containing the lyophilized activated polysaccharide were stored at -20°C. The calculated amount of CRM ₁₉₇ protein (target S/P input ratio = 1) was frozen in the shell and lyophilized separately. Lyophilized CRM ₁₉₇ was stored at -20°C.

b. Recovery of lyophilized activated polysaccharide and CRM ₁₉₇ protein

The lyophilized activated polysaccharide was reconstituted in anhydrous dimethyl sulfoxide (DMSO). After complete dissolution of the polysaccharide, the same amount of anhydrous DMSO was added to the lyophilized CRM ₁₉₇ for reconstitution.

c. Conjugation of activated polysaccharide with CRM ₁₉₇ and blocking

The reduced CRM ₁₉₇ (in DMSO) was mixed in a conjugation reaction vessel with the reduced activated polysaccharide. The final concentration of the polysaccharide in the reaction solution is 1 g/l. Conjugation was initiated by adding 1.5 M-eq. to the reaction mixture. sodium cyanoborohydride, and the reaction was incubated at 23°C for 20 hours. Completion of the conjugation reaction was carried out by adding 2 M-eq. sodium borohydride. The blocking reaction was incubated at 23°C for 3 hours.

d. Purification of the conjugate

The conjugate solution was diluted 1:5 with chilled 5 mM succinate - 0.9% saline (pH 6.0) to be purified by tangential flow filtration using 100K MWCO membranes, and 20X diafiltration was performed using 5 mM succinate - 0.9% saline solution (pH6.0) as medium. After diafiltration was completed, the conjugate rethenate was further diluted, filtered through a 0.22 μm filter and stored at 2-8°C.

Several conjugates were prepared using the method described above by varying various parameters (eg, saccharide-protein input ratio, reaction concentration, and M-eq. sodium cyanoborohydride). Characterization for the presented Pn-22F glycoconjugates with CRM ₁₉₇ are shown in Table 16

The level of %O-Acetyl (retained) in the final conjugate was calculated by the ratio of the O-Acetyl content of the conjugate (µmol O-Acetyl per µmol serotype 22F saccharide repeat unit) relative to the polysaccharide O-Acetyl content (µmol O-Acetyl per µmol serotype 22F saccharide repeat unit) ).

The immunogenicity of the conjugates prepared above was evaluated using the opsonophagocytic activity (OPA) assay, which is described below. Groups of thirty 6-7 week old female Swiss Webster mice were immunized with 0.001 μg, 0.005 μg, or 0.01 μg of the test conjugates by subcutaneous injection at 0 weeks of age. Mice were boosted with the same dose of conjugate at 3 weeks of age and then bled at 4 weeks of age. Serotype-specific ORAs were performed on 4 week old sera samples.

Opsonophagocytic activity assays (OPAs) are used to measure functional antibodies in mouse sera specific for S. pneumoniae serotype 22F. The studied serum was introduced into test reactions that measure the ability of the capsular polysaccharide of a specific immunoglobulin to opsonize a bacterium, deposition a trigger complement, thereby facilitating phagocytosis and destroying bacteria with the help of phagocytes. The OPA titer is defined as the reciprocal dilution that results in a 50% reduction in bacteria compared to control wells without test serum. The OPA titer is interpolated from two dilutions that cover a given 50% kill cutoff.

OPA procedures were based on the methods described in Hu et al. (2005) Clin Diagn Lab Immunol12 (2): 287-295 with the following modifications. The test serum was serially diluted 2.5-fold and added to microtiter plates for analysis. Live target bacterial strains of serotype 22F were added to the wells and the plates were shaken at 25°C for 30 minutes. Differentiated HL-60 cells (phagocytes) and baby rabbit serum (3-4 weeks old, PEL-FREES®, 12.5% final concentration) were added to the wells and the plates were shaken at 37° C. for 45 minutes. To terminate the reaction, 80 μl of 0.9% NaCl was added to all wells, mixed, and a 10 μl aliquot was transferred to the wells of MULTISCREEN® HTS HV filter plates (MILLIPORE®) containing 200 μl of water. The liquid was filtered with the plates under vacuum and 150 μl of HYSOY® medium was added to each well and filtered again. The filter plates were then incubated at 37° C., 5% CO ₂ overnight and then fixed with a bleach solution (Bio-Rad Laboratories, Inc., Hercules, CA). The plates were then stained with Coomassie blue and decolorized once. Colonies were examined and listed using the Cellular Technology Limited (CTL) (Shaker Heights, OH) IMMUNOSPOT® analyzer. Raw colony counts were used to plot kill curves and calculate OPA titers. Titers of opsonophagocytic activity (OPA) for conjugates serotype 22F-CRM ₁₉₇ were determined as described above. OPA titers (geometric mean titer (GMT) with 95% confidence interval (CI)) after four weeks at various doses are shown in Tables 17 to 18, (two separate experiments), demonstrating that the serotype 22F conjugate (batches 1-7; also see Table 16 for characterization data of these conjugates) elicited OPA titers in a mouse immunogenicity model.

Example 14 Preparation of Pn-11A Conjugates with CRM ₁₉₇

Preparation of Pn-11A RAC Glycoconjugates The frozen, sized polysaccharide, which was stored in deionized water or 25 mM potassium phosphate buffer (pH 6.0), was thawed at 5°C.

Polysaccharide oxidation

Polysaccharide oxidation was carried out in 100 mM potassium phosphate buffer (pH 6.0) by adding 500 mM potassium phosphate buffer (pH 6.0) and WFI to give a final polysaccharide concentration of 2.0 g/l. The oxidation reaction was carried out at 23°C. The oxidation was initiated by adding sodium periodate. The stirring speed was in the range of 100-140 rpm.

Purification of activated polysaccharide 11A

The concentration and diafiltration of the activated polysaccharide was carried out using ultrafiltration cassettes. Diafiltration was performed against 20 times the diavolume of WFI. After filtration through 0.22 μm, the purified activated polysaccharide was stored at 5°C.

Description of the conjugation process

The conjugation process includes the following steps:

a. Freezing in the shell and lyophilization of the protein CRM ₁₉₇ ;

b. Recovery of activated polysaccharide and CRM ₁₉₇ ;

c. Conjugation of the activated polysaccharide with CRM ₁₉₇ ; and

d. Purification and dilution of the conjugate

a. Freezing in the shell and lyophilization of the protein CRM ₁₉₇

The CRM ₁₉₇ protein was frozen in the shell and lyophilized.

b. Recovery of activated polysaccharide and protein CRM ₁₉₇

The activated polysaccharide solution (~10 g/l) was loaded into the reactor followed by the addition of a calculated amount of 0.5N sodium phosphate buffer (pH 7.2). With stirring, lyophilized CRM ₁₉₇ was added and the reaction mixture was stirred for 2-4 hours in order to achieve complete dissolution of CRM ₁₉₇ .

With. Conjugation and blocking

Conjugation was initiated by adding cyanoborohydride. The reaction mixture was incubated at 23°C for 72-96 hours. Completion of the conjugation reaction was accomplished by adding 0.5X WFI followed by 2 M-eq. sodium borohydride. This blocking reaction was kept at 23° C. for 3-4 hours.

d. Dilution and initial purification of the conjugate

The conjugate solution was diluted 1:5 (reaction volume) with 0.15N sodium phosphate buffer (pH 8.0) to be purified by tangential flow filtration (TFF). The diluted conjugate was mixed in a dilution vessel and then passed through a 5 µm filter. The filtered conjugate solution was then concentrated to 1-2 g/l. Conducted a two-stage method of diafiltration. In the first step, TFF was performed using 30X (diafiltration volume) 0.15N sodium phosphate buffer (pH 8.0) followed by 20X 5 mM succinate-0.9% NaCl (pH6.0). After the initial diafiltration was completed, the conjugate rethenate was transferred through a 0.4 5 µm filter into a collection vessel.

Final diafiltration of the conjugate

The final purification step was 20X diafiltration with 5 mM succinate-0.9% NaCl, pH 6.0 medium using regenerated cellulose membranes.

Monovalent Bulk Conjugate (MVC) Dilutions

The conjugate was further diluted with 5 mM succinate/0.9% NaCl, pH 6 to a target saccharide concentration of 0.5 mg/mL. A final 0.22 µm filtration step was completed, yielding a monovalent bulk conjugate (MBC) product for the formulation.

Several conjugates were prepared using the methods described above by varying various parameters (eg, saccharide-protein input ratio, reaction mixture concentration, and M-eq. sodium cyanoborohydride). Characterization for the presented glycoconjugates of Pb-11A with CRM ₁₉₇ are shown in table 19 (batch 1-5).

Preparation of Pn-11A glycoconjugates using RAC/DMSO

The oxidized polysaccharide was prepared and purified as described above (see preparation of Pn-11A RAC glycoconjugates).

Conjugation via reductive amination in DMSO (RAC/DMSO)

Conjugation of 11A by RAC/DMSO included the following steps:

a. Mixing with sucrose, freezing in the shell and lyophilization;

b. Recovery of lyophilized polysaccharide and CRM ₁₉₇ ;

c. Conjugation of the activated polysaccharide with CRM ₁₉₇ ; and

d. Purification and dilution of the conjugate.

a. Mixing with sucrose, freezing in the shell and lyophilization

Activated polysaccharide, obtained by sorting by size of the polysaccharide, was mixed with sucrose (50% w/v in WFI) at a ratio of 25 grams of sucrose per gram of activated polysaccharide. The components were mixed in a coated freezer vial, the compounded mixture was then lyophilized. CRM ₁₉₇ protein was frozen coated and lyophilized separately.

b. Recovery of lyophilized activated polysaccharide and CRM ₁₉₇ protein

The lyophilized activated polysaccharide was reconstituted in DMSO to a concentration of 2 mg/ml. After completion of the dissolution of the polysaccharide, DMSO was added to the lyophilized CRM ₁₉₇ to restore

c. Conjugation and blocking

The reduced CRM ₁₉₇ (in DMSO) was mixed in a conjugation reaction vessel with the reduced activated polysaccharide. The final concentration of the polysaccharide in the reaction solution is 1 g/l. Conjugation was initiated by adding cyanoborohydride to the reaction mixture and incubated at 23°C for 22 hours. Completion of the conjugation reaction was carried out by adding 2 M-eq. sodium borohydride. This blocking reaction was kept at 23° C. for 3-4 hours.

d. Purification and dilution of the conjugate

The conjugate solution was purified and diluted using the same method as described above.

Several conjugates were prepared using the method described above by varying various parameters (eg, saccharide-protein input ratio, reaction concentration, and M-eq. sodium cyanoborohydride). Characterization for the presented glycoconjugates of Pn-11A with CRM ₁₉₇ obtained according to the method above, are shown in table 19 (batch 6-8).

The overall data obtained from conjugates prepared using the above reductive amination processes demonstrated that this allowed the preparation of conjugates with good conjugation yield, low % free saccharide and good stability.

The immunogenicity of the conjugates prepared above was evaluated using the opsonophagocytic activity (OPA) assay, which is described below.

Groups of 30 6-7 week old female Swiss Webster mice were immunized with 0.001 µg, 0.005 µg, 0.01 µg, or 0.1 µg of the test conjugates via subcutaneous administration at 0 weeks of age. Mice were boosted with the same dose of conjugate at 3 weeks of age and then bled at 4 weeks of age. Serotype-specific ORAs were performed on 4 week old sera samples.

Opsonophagocytic activity assays (OPAs) are used to measure functional antibodies in mouse sera specific for S. pneumoniae serotype 11A. The studied serum was introduced into test reactions that measure the ability of the capsular polysaccharide of a specific immunoglobulin to opsonize a bacterium, deposition a trigger complement, thereby facilitating phagocytosis and destroying bacteria with the help of phagocytes. The OPA titer is defined as the reciprocal dilution that results in a 50% reduction in bacteria compared to control wells without test serum. The OPA titer is interpolated from two dilutions that cover a given 50% kill cutoff.

OPA procedures were based on the methods described in Hu et al. (2005) Clin Diagn Lab Immunol12 (2): 287-295 with the following modifications. The test serum was serially diluted 2.5-fold and added to microtiter plates for analysis. Live target bacterial strains of serotype 11A were added to the wells and the plates were shaken at 25°C for 30 minutes. Differentiated HL-60 cells (phagocytes) and baby rabbit serum (3-4 weeks old, PEL-FREES, 12.5% final concentration) were added to the wells and the plates were shaken at 37°C for 60 minutes. To terminate the reaction, 80 μl of 0.9% NaCl was added to all wells, mixed, and a 10 μl aliquot was transferred to the wells of MULTISCREEN® HTS HV filter plates (MILLIPORE®) containing 200 μl of water. The liquid was filtered through the plates under vacuum and 150 μl of HYSOY® medium was added to each well and filtered through. The filter plates were then incubated at 37° C., 5% CO ₂ overnight and then fixed with a bleach solution (Bio-Rad Laboratories, Inc., Hercules, CA). The plates were then stained with Coomassie blue and decolorized once. Colonies were examined and listed using the Cellular Technology Limited (CTL) (Shaker Heights, OH) IMMUNOSPOT® analyzer. Raw colony counts were used to plot kill curves and calculate OPA titers.

Opsonophagocytic activity (OPA) titers for the 11A-CRM ₁₉₇ serotype conjugates in mice were determined as described above. OPA titers (geometric mean titer (GMT) with 95% confidence interval (CI)) after four weeks at various doses are shown in Table 20, demonstrating that the serotype 11A conjugate (lots 2-4 and 8; also see Table 19 for characterization data of these conjugates) elicited OPA titers in a mouse immunogenicity model.

Example 15 16-valent Pneumococcal Conjugate Vaccine Preparation

16-valent conjugated composition containing glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F and 33F (16vPnC) all individually conjugated to CRM ₁₉₇ has been formulated.

Glycoconjugates from S. pneumoniaeoi serotypes 15B, 22F, and 33F were prepared as described above, and glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F were obtained as disclosed in WO 2006/110381. The required volumes of compound concentrates were calculated based on batch volume and compound saccharide concentrations. The formulated compound vaccine was prepared by adding the required volume of NaCl/succinate buffer (pH 5.8) in order to obtain a final target concentration of 5.0 mM succinate buffer and 150 mM NaCl. Added polysorbate 80 to a final concentration of 0.02% and 16 pneumococcal conjugates. The resulting mixture was filtered through a 0.2 µm Millipore PES membrane, followed by the addition of AlPO4. The preparation was stirred to allow binding and in order to achieve homogeneity.

The drug was then filled into glass syringes to deliver a 0.5 ml dose.

The final dosage form contained 2.2 μg each of S. pneumoniae serotypes 1, 3, 4, 5, 6A, 7F, 9V, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F glycoconjugates individually conjugated to CRM ₁₉₇ , 4.4 μg S. pneumoniae serotype 6B glycoconjugate, 5 mM succinate buffer pH 5.8, 0.02 PS80, 150 mM NaCl, and 0.25 mg/ml aluminum as AlPO ₄ for a 0.5 ml dose. The CRM ₁₉₇ content was approximately 38 μg for a 0.5 ml dose.

Example 16 20-valent Pneumococcal Conjugate Vaccine Preparation

20 valent conjugated composition containing glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F and 33F (20vPnC) all individually conjugated to CRM ₁₉₇ was formulated.

Glycoconjugates from S. pneumoniae serotypes 8, 10A, 11A, 12F, 15B, 22F, and 33F were prepared as described above, and glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14 , 18C, 19A, 19F and 23F were prepared as disclosed in WO 2006/110381.

The required volumes of compound concentrates were calculated based on batch volume and compound saccharide concentrations. The formulated compound vaccine was prepared by adding the required volume of NaCl/succinate buffer (pH 5.8) to obtain a final target concentration of 5.0 mM succinate buffer and 150 mM NaCl. Polysorbate 80 was added to a final concentration of 0.02% and 20 pneumococcal conjugates. The resulting mixture was filtered through a 0.2 μm Millipore PES membrane, followed by the addition of AlPO ₄ . The preparation was well mixed to obtain maximum binding of the conjugates to aluminum.

The drug was then filled into glass syringes to deliver a 0.5 ml dose.

The final dosage form contained 2.2 μg each of S. pneumoniae serotypes 1, 3, 4, 5, 6A, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F glycoconjugates. and 33F separately conjugated to CRM ₁₉₇ , 4.4 μg S. pneumoniae serotype 6B glycoconjugate, 5 mM succinate buffer pH 5.8, 0.02 PS80, 150 mM NaCl, and 0.25 mg/ml aluminum as AlPO ₄ for a dose of 0.5 ml. The CRM ₁₉₇ content was approximately 46 μg for a 0.5 ml dose.

Example 17 Immunogenicity of a 16-valent immunogenic composition

The immunogenicity of the 16-valent immunogenic composition (see Example 15) was evaluated in rabbits using Luminex multiplex direct immunoassays (dLIAs) to measure serotype-specific IgG serum concentrations and serotype-specific OPA. Groups of ten female New Zealand white rabbits weighing 2.5 kg to 3.5 kg were immunized with the proposed human clinical dose (2.2 µg conjugate except for serotype 6B, which was taken at 4.4 µg; plus 0.1 mg aluminum as AlPO ₄ ) were injected intramuscularly at 0 weeks of age. Rabbits were boosted with the same dose of the conjugate vaccine at 2 weeks of age and then bled at 4 weeks of age. Serotype-specific dLIA and OPA were performed on week 0 and week 4 sera samples.

To quantify the total binding of polysaccharide antibodies (IgG) specific for each pneumococcal polysaccharide (PNP), rabbit sera were assessed in two direct Luminex immunoassays (dLIAs, 13-Plex dLIA, Prevnar 13® serotypes and 7-Plex dLIA, additional serotypes) . The 13-Plex assay measures anti-PnPS antibodies specific to 13 serotypes included in the 13-valent pneumococcal conjugate (PnC) vaccine (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F) and anti-PnPS antibodies to additional serotypes (15B, 22F, 33F) are measured in a 7-Plex assay. Each assay contains a combination of 13 or 7 spectrally different magnetic beads coupled to PnPS conjugates (PnPS-PLL conjugates: PnPS conjugated to poly-L-lysine).

Briefly, the reference standard, controls, and test sera were first pre-adsorbed onto two Pn adsorbents; CWPS1 (PnA cell wall polysaccharide containing C-polysaccharide) and CWPS2 (CWP of capsular S. pneumoniae serotype 2) in order to block the binding of non-specific antibodies to the PnPS coating antigen. After pre-adsorption, PnPS-bound microspheres were incubated with appropriately diluted serum reference standard, controls, or test rabbit sera. After incubation, each mixture was washed and R-phycoerythrin-conjugated goat anti-rabbit IgG secondary antibody was added. Fluorescence signals (expressed as mean fluorescence intensity (MFI)) were measured using a Bio-Plex reader and correlated with the amount of bound PnPS-specific IgG. Values for subjects were reported as (units/ml, units/ml). Serotype-specific ORAs were performed as described above. The OPA titer is the reciprocal of the highest dilution of serum resulting in a 50% reduction in bacterial colony forming units (CFU) compared to a no serum control (defined as background CFU). The titer is interpolated from two dilutions that cover a given 50% kill cut.

The results showed a significant increase in serotype-specific IgG and functional OPA antibody responses after two 16vPnC immunizations (Table 21). Serum IgG levels increased more than 2-log above baseline. Similarly, a reliable functional OPA antibody response caused a minimum of 22-fold increase in GMT OPA above baseline. Immunization sera (Wek 0) showed undetectable levels of PnPS-specific IgG and functional OPA antibodies for most 16v Pn serotypes except for serotypes 14 and 33F. Low levels of OPA titers were present in these serotypes, but these baseline responses did not adversely affect the antibody response after vaccination.

Example 18 Immunogenicity of a 20-valent immunogenic composition

The immunogenicity of the 20-valent immunogenic composition (as prepared in Example 16) was evaluated in rabbits using Luminex multiplex direct immunoassays (dLIAs) to measure serotype-specific IgG serum concentrations and serotype-specific OPA.

Groups of ten female New Zealand white rabbits weighing 2.5 kg to 3.5 kg were immunized with the proposed human clinical dose (2.2 µg conjugate except for serotype 6B, which was taken at 4.4 µg; plus 0.1 mg aluminum as AIPO4 ) was administered intramuscularly at 0 weeks of age. Rabbits were boosted with the same dose of the conjugate vaccine at 2 weeks of age and then bled at 4 weeks of age. Serotype-specific dLIA and OPA were performed on week 0 and week 4 sera samples.

To quantify the total binding of polysaccharide antibodies (IgG) specific for each pneumococcal polysaccharide (PNP), rabbit sera were assessed in two direct Luminex immunoassays (dLIAs, 13-Plex dLIA, Prevnar 13® serotypes and 7-Plex dLIA, additional serotypes) . The 13-Plex assay measures anti-PnPS antibodies specific to 13 serotypes included in the 13-valent pneumococcal conjugate (PnC) vaccine (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F) and anti-PnPS antibodies to additional serotypes (15B, 22F, 33F) are measured in a 7-Plex assay. Each assay contains a combination of 13 or 7 spectrally different magnetic beads coupled to PnPS conjugates (PnPS-PLL conjugates: PnPS conjugated to poly-L-lysine).

Briefly, the reference standard, controls, and test sera were first pre-adsorbed onto two Pn adsorbents; CWPS1 (PnA cell wall polysaccharide containing C-polysaccharide) and CWPS2 (CWP of capsular S. pneumoniae serotype 2) in order to block the binding of non-specific antibodies to the PnPS coating antigen. After pre-adsorption, PnPS-bound microspheres were incubated with appropriately diluted serum reference standard, controls, or test rabbit sera. After incubation, each mixture was washed and R-phycoerythrin-conjugated goat anti-rabbit IgG secondary antibody was added. Fluorescence signals (expressed as mean fluorescence intensity (MFI)) were measured using a Bio-Plex reader and correlated with the amount of bound PnPS-specific IgG. Values for subjects were reported as (units/ml, units/ml).

Serotype-specific ORAs were performed as described above. The OPA titer is the reciprocal of the highest dilution of serum resulting in a 50% reduction in bacterial colony forming units (CFU) compared to a no serum control (defined as background CFU). The titer is interpolated from two dilutions that cover a given 50% kill cut.

Rabbits immunized with 20vPnC also showed significant increases in total IgG and functional OPA antibody titers against serotypes common to 16v and 20v preparations, as well as an additional four serotypes (8, 10A, 11A, and 12F) (Table 22). A 2-log increase in serum IgG levels for a population of 20 serotypes was induced after two immunizations. The OPA of vaccine-induced GMT was at least 27 times baseline. Low OPA titers in pre-immunization sera for serotypes 4 and 33F were similarly observed after 20vPnC vaccination, but again did not alter the robustness of post-vaccination antibody responses. The 16vPnC to 20vPnC preparations elicited a sustained humoral response that was both specific to pneumococcal polysaccharides and associated with functional killing of the bacterium (see Tables 21 and 22). In conclusion, the studies shown in examples 17 and 18 demonstrated good immunogenicity of both 16vPnC and 20vPnC preparations.

Example 19 Assessment of cross-reactive opsonophagocytic immune responses within serogroup 9 of Streptococcus pneumoniae

The pneumococcal opsonophagocytic activity assay (OPA), which measures the killing of S. pneumoniae cells using phagocytic effector cells in the presence of a functional antibody and complement, is considered to be an important surrogate for evaluating the effectiveness of pneumococcal vaccines.

Materials and Methods

Two randomly selected subsets of immune sera from adults vaccinated with a 13-valent pneumococcal conjugate vaccine (13vPnC) were examined in OPA analyzes for serotypes 9B, 9A, 9L and 9N. Sera were collected from US clinical trials 6115A1-004 (N=59, post-vaccination) and 6115A1-3005 (N=66, match before and after vaccination), respectively.

Study 6115A1-3005 (Clinical Trials - Government Identifier: NCT00546572) was a phase 3, randomized, active-controlled, modified, double-blind study to evaluate the safety, tolerability, and immunogenicity of Prevnar 13 versus 23-valent pneumococcal polysaccharide vaccine (23vPS) in elderly outpatients 70 years of age or older who received 1 dose of 23vPS at least 5 years prior to study enrollment (see: http://http://clinicaltrials.gov/ct2/show/NCT00546572; available 31 March, 2014). Study 6115A1-004 (Clinical Trials - Government Identifier: NCT00427895) was a Phase 3, randomized, active-controlled, modified, double-blind study to evaluate the safety, tolerability, and immunogenicity of a 13-valent pneumococcal conjugate vaccine (13vPnC) versus a 23- valence pneumococcal polysaccharide vaccine (23vPS) in adults aged 60 to 64 years who are native to 23vPS, and the safety, tolerability and immunogenicity of 13vPnC in adults aged 18 to 59 years who are native to 23vPS (see: http: //clinicaltrials.gov/show/NCT00427895; accessed March 31, 2014).

The 13-valent pneumococcal conjugate vaccines (13vPnC) tested in these studies contained conjugates from pneumococcal serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F, separately conjugated with diphtheria cross-reacting material 197 (CRM ₁₉₇ ) carrier protein.

OPAs are used to measure functional antibodies in human sera against S. pneumoniae serotypes 9V, 9N, 9A and/or 9L. The studied serum was introduced into test reactions that measure the ability of the capsular polysaccharide of a specific immunoglobulin to opsonize a bacterium, deposition a trigger complement, thereby facilitating phagocytosis and destroying bacteria with the help of phagocytes. The OPA titer is defined as the reciprocal dilution that results in a 50% reduction in bacteria compared to control wells without test serum. The OPA titer is interpolated from two dilutions that cover a given 50% kill cutoff.

OPA procedures were based on the methods described in Hu et al. (2005) Clin Diagn Lab Immunol122): 287-295. The heat-inactivated serum to be tested was serially diluted 2.5-fold and added along with the target bacteria to the assay plates and incubated for 30 minutes with shaking. Differentiated HL-60 cells (phagocytes) and baby rabbit sera (3-4 weeks old, PEL-FREES®, Arkansas, 12.5% final concentration) were then added to the wells, at a ratio of fit effector to target of 200:1, and incubated at 37°C with shaking. To terminate the reaction, 80 μl of 0.9% NaCl was added to all wells, mixed, and a 10 μl aliquot was transferred to the wells of MULTISCREEN® HTS HV filter plates (MILLIPORE®) containing 200 μl of water. The liquid was filtered with vacuum plates and 150 μl of HYSOY® medium was added to each well and filtered through the filter plates, then incubated at 37°C, 5% CO ₂ overnight and then fixed with a decolorizing solution (Bio-Rad Laboratories, Inc., Hercules, Calif.). The plates were then stained with Coomassie blue and decolorized once. Colonies were examined and listed using the Cellular Technology Limited (CTL) (Shaker Heights, OH) IMMUNOSPOT® analyzer.

Statistical analysis: Two-way Pearson correlations were calculated.

Results - OPA responses in 9V, 9A, 9L and 9N

Cross-functional response from immune sera from adults immunized against 13vPnC serotypes 9a, 9L, and 9N was assessed in the appropriate microcolony opsonophagocytic activity assay (mcOPAs), along with homologous functional response to serotype 9V. Two randomly selected subsets of immune sera from adults vaccinated with 13vPnC were tested. Sera were collected from US clinical trials 6115A1-004 (N=59, post-vaccination) and 6115A1-3005 (N=66, match before and after vaccination), respectively.

Subjects in study 6115A1-004 were previously native to any pneumococcal vaccination and received a single dose of 13vPnC as part of the study protocol. Immune sera from study 6115A1-004 show a similar percentage of responders for all serogroups with values of 98.3%, 98.3%, 100% and 93.2% for 9V, 9A, 9L and 9N, respectively (Figure 11), maintaining results 6115A1-3005 (figure 12). Relatively good correlations of OPA titers were observed between serotypes 9V and 9A (Pearson correlations ρ=0.5456, p<0.0001) or 9L (ρ=0.7353, p<0.0001), but not with 9N (ρ=0 .1217, p<0.3627).

Subjects in study 6115A1-3005 had previously received 1 dose of 23vPS at least 5 years prior to study entry and received one dose of 13vPnC as part of the study protocol. A corresponding panel of pre- and post-vaccination sera (N=66) from adults immunized with 13vPnC (study 6115A1-3005) was evaluated for OPA for homologous response to serotype 9V and for cross-reactivity of anti-9V antibodies to serotypes 9A, 9L and 9N. As shown in Figure 12, relatively high immunity (percentage of responders) to 9V (84%), 9A (66%), 9L (82%) and 9N (86%) was found in the OPA analysis of probable due to their previous 23vPS immunization. , which includes unconjugated polysaccharides from serotypes 9V and 9N. However, the percentage of responders increased to 95% or more for all four serotypes after vaccination with 13vPnC, which contains only serogroup 9 serotype 9V conjugate. Multiple fold increases in titer values are shown in Table 23 and are similar to serotypes also suggesting cross-reactivity.

A large comprehensive analysis of the OPA titer distribution is shown in the inverse cumulative distribution curves (RCDC) in Figures 13-16. RCDCs show an increase in serotype-specific immune response after vaccination for serotypes 9V, 9A, 9L, and to a lesser extent 9N. Titer fold correlations of individual hits/samples from 9V 9A, 9V/9L and 9V/9N were also analyzed using Pearson's correlation. Relatively good correlations were observed in the fold increase in titers from serotypes 9V and 9A (Pearson correlation ρ=0.8720, p<0.0001) or 9N (ρ=0.5801, p<0.0001), but to a lesser extent with 9L ( ρ=0.1804, p<0.1640).

Conclusion

Based on these data, the 13vPnC vaccine should likely provide broader serotype coverage, providing additional protection against serotypes 9A, 9L and 9N.

Example 20: Cross-functional OPA responses to serotype 15B and serotype 15C

Pneumococcal serogroup 15 includes four structurally related serotypes: 15A, 15B, 15C, and 15F. Serotypes 15B and 15C are indistinguishable genetic typing methods and have a similar capsular polysaccharide (PS) structure, except that 15B-PS is an O-acetylated variant of 15C-PS. In order to understand whether PS anti-capsular antibodies to serotype 15B have cross-interaction functionality to serotype 15C, 10 rabbits were immunized with 16vPnC (see Example 15) and 20vPnC (see Example 16) and vaccines containing an immunogenic conjugate containing a capsular polysaccharide S. pneumoniae, serotype 15b, covalently associated with CRM ₁₉₇ as disclosed in this document, as part of their preparation. Pre- and post-vaccination sera were tested in OPA assays against 15B and 15C serotypes of target pneumococcal strains.

Of 10 rabbits from each group, 100% had an OPA response to serotype 15B after immunization with serotype 15B conjugate. Of these same samples, 100% had an OPA response also to serotype 15C (Table 24 and Table 25). Low OPA titers were observed in serum before 15C OPA vaccination. However, a more than 10-fold GMT OPA increase in serum titer after vaccination compared to before vaccination showed that the immunogenic conjugates of the invention induce the production of antibodies capable of killing Streptococcus pneumoniae serotype 15B and 15C in OPA.

All publications and patent applications mentioned in the description show the state of the art for specialists in the field to which this invention pertains. All publications and patent applications are incorporated into this specification by reference, as if each individual publication or patent application were specifically and separately indicated for inclusion by reference.

Although the present invention has been described in detail by means of illustrations and examples for the purposes of clarity of understanding, certain changes and modifications may be made within the scope of the appended claims.

Claims (19)

1. An immunogenic composition for use as a vaccine to prevent a disease or condition associated with S. pneumoniae, containing a glycoconjugate from S. pneumoniae serotype 22F and an excipient, where the glycoconjugate has a molecular weight of 1000 to 12500 kDa and is a conjugate of an isolated capsular polysaccharide from S. pneumoniae serotype 22F and carrier protein, where the ratio (w/w) of polysaccharide to carrier protein is from 0.5 to 2 and where said carrier protein is CRM ₁₉₇ , where each dose contains from 0.1 to 100 μg of 22F polysaccharide . 2. An immunogenic composition according to claim 1, further comprising at least one glycoconjugate from S. pneumoniae serotype 15B and at least one glycoconjugate from S. pneumoniae serotype 33F. 3. The immunogenic composition according to claim 1, further comprising at least one glycoconjugate from S. pneumoniae serotype 15B, at least one glycoconjugate from S. pneumoniae serotype 33F, at least one glycoconjugate from S. pneumoniae serotype 12F, at least one glycoconjugate from S. pneumoniae serotype 10A, at least one glycoconjugate from S. pneumoniae serotype 11A, and at least one glycoconjugate from S. pneumoniae serotype 8. 4. The immunogenic composition according to claim 1, additionally containing glycoconjugates from S. pneumoniae serotypes 4, 6B, 9V, 14, 18C, 19F and 23F. 5. The immunogenic composition according to claim 1, additionally containing glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F and 23F. 6. The immunogenic composition according to claim 1, additionally containing glycoconjugates from S. pneumoniae serotypes 1, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F. 7. An immunogenic composition according to claim 1, additionally containing glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F. 8. The immunogenic composition according to claim 1, additionally containing glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F. 9. An immunogenic composition according to claim 1, additionally containing glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 15B, 18C, 19A, 19F, 23F and 33F. 10. Immunogenic composition according to claim 1, additionally containing glycoconjugates from S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F , 23F and 33F. 11. Immunogenic composition according to any one of paragraphs. 1-10, which is an 8-, 9-, 10-, 11-, 12-, 13-, 14-, 15-, 16-, 17-, 18-, 19- or 20-valent pneumococcal conjugate composition. 12. Immunogenic composition according to any one of paragraphs. 1-11, where these glycoconjugates are individually conjugated to CRM ₁₉₇ . 13. Immunogenic composition according to any one of paragraphs. 2, 3 or 9, 10, wherein said serotype 15B glycoconjugate has a molecular weight of 1000 to 7500 kDa. 14. Immunogenic composition according to any one of paragraphs. 2, 3 or 9, 10, wherein said serotype 33F glycoconjugate has a molecular weight of 2000 to 6000 kDa. 15. Immunogenic composition according to any one of paragraphs. 3, 10, where said serotype 12F glycoconjugate has a molecular weight of 1000 to 4000 kDa. 16. Immunogenic composition according to any one of paragraphs. 3, 10, where said serotype 10A glycoconjugate has a molecular weight of 3000 to 7500 kDa. 17. Immunogenic composition according to any one of paragraphs. 3, 10, where the specified serotype 11A glycoconjugate has a molecular weight from 500 to 12500 kDa. 18. Immunogenic composition according to any one of paragraphs. 3, 10, where said serotype 8 glycoconjugate has a molecular weight of 3,000 to 15,000 kDa. 19. Immunogenic composition according to any one of paragraphs. 1-11, where the specified immunogenic composition additionally contains at least one adjuvant.

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