WO2021255648A1

WO2021255648A1 - Hyperimmune globulins for treatment of influenza a

Info

Publication number: WO2021255648A1
Application number: PCT/IB2021/055283
Authority: WO
Inventors: Christine Hall; Debbie ANDERSON; Tim BABINCHAK; Amy DAHL; Priya UPPIN; Hugo ASTACIO; Duli PODDAR
Original assignee: Emergent Biosolutions Canada Inc.
Priority date: 2020-06-15
Filing date: 2021-06-15
Publication date: 2021-12-23

Abstract

The present disclosure is directed to methods of using mixtures of anti-influenza immune globulins and/or antigen-binding fragments thereof to treat influenza A infections in human patients.

Description

HYPERIMMUNE GLOBULINS FOR TREATMENT OF INFLUENZA A CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the priority benefit of U.S. Provisional Application

Number 63/039,341, filed on June 15, 2020, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] Seasonal influenza remains a significant disease burden worldwide that can result in severe disease, hospitalization, and even mortality in vulnerable populations such as the elderly. Even with the use of vaccines and antivirals, seasonal influenza causes significant morbidity and mortality around the world each year. In spite of the large disease burden, studies have failed to definitively demonstrate substantial clinical efficacy of an antiviral drug in hospitalized influenza patients. Therefore, there is a need for more effective treatments for influenza, including severe and hospitalized cases of influenza.

BRIEF SUMMARY OF THE INVENTION

[0003] Provided herein are methods of treating influenza. In some aspects, a method of treating an influenza A infection in a human patient comprises administering to the patient an effective amount of a composition comprising a mixture of human anti influenza A immune globulins or antigen-binding fragments thereof. In some aspects, the administration decreases the patient’s ordinal scale score. In some aspects, the administration decreases the patient’s ordinal scale score within 4 days. In some aspects, the administration decreases the patient’s ordinal scale score within 8 days In some aspects, the administration decreases the duration of the patient’s hospital stay. In some aspects, the administration decreases the amount of time the patient needs supplemental oxygen. In some aspects, the administration increases hemagglutination inhibition (HAI) titers in the patient. In some aspects, the administration increases anti-influenza A antibody levels as measured by HAI. In some aspects, the administration increases HAI titers in the patient within 2 days of the administration. In some aspects, the administration increases microneutralization (MN) in the patient. In some aspects, the administration increases microneutralization (MN) in the patient within 2 days of administration. In some aspects, the administration increases influenza virus neutralization titers as measured by microneutralization (MN) assay in the patient. In some aspects, the administration increases influenza virus neutralization titers as measured by MN assay in the patient within 2 days of the administration.

[0004] In some aspects, the influenza A infection is a seasonal influenza A infection. In some aspects, the influenza subtype is H3N2. In some aspects, the influenza subtype is H1N1. In some aspects, the influenza subtype is H1N1 or H3N2.

[0005] In some aspects, the patient is hospitalized. In some aspects, the patient is in an intensive care unit (ICU). In some aspects, the patient was admitted to the hospital through the emergency room (ER). In some aspects, the patient is in the observation unit. In some aspects, the patient is planned to be hospitalized in the opinion of the attending physician. In some aspects, the patient has severe influenza A. In some aspects, the patient is hospitalized with serious illness caused by influenza A infection. In some aspects, the patient is hospitalized with severe influenza. In some aspects, the patient is hospitalized with laboratory confirmed influenza A infection. In some aspects, the patient is hospitalized with influenza A infection.

[0006] In some aspects, the mixture is administered intravenously.

[0007] In some aspects, the mixture is administered within 6 days of onset of illness. In some aspects, the mixture is administered within 5 days of onset of illness. In some aspects, the mixture is administered within 4 days of onset of illness. In some aspects, the mixture is administered within 3 days of onset of illness. In some aspects, the mixture is administered within 2 days of onset of illness. In some aspects, the mixture is administered within 1 day of onset of illness.

[0008] In some aspects, the method further comprises administering an anti-viral drug.

The anti-viral drug can be, e.g., oseltamivir phosphate, zanamivir, peramivir, or baloxavir marboxil. In some aspects, the anti-viral drug is administered for at least five days. In some aspects, the method further comprises administering oseltamivir. In some aspects, the oseltamivir is administered for at least five days. In some aspects, the oseltamivir is administered for 5 days at a dose of 75 mg/day. In some aspects, the method further comprises administering standard of care in addition to the mixture, including supportive measures, ventilator and fluid management and the prevention and treatment of secondary bacterial pneumonia.

[0009] In some aspects, the mixture comprises 65 milligrams of protein /milliliter (mL).

In some aspects, the mixture comprises between 40 and 70 milligrams (mg) of protein /milliliter (mL). In some aspects, the mixture comprises 60 to 65 mg milligrams (mg) of protein /milliliter (mL), e.g., about 63 milligrams (mg) of protein /milliliter (mL). In some aspects, the mixture comprises 30 to 35 mg milligrams (mg) of protein /milliliter (mL), e.g., about 32 milligrams (mg) of protein /milliliter (mL).

[0010] In some aspects, 450 mL of the mixture is administered. In some aspects, 225 mL of the mixture is administered. In some aspects, about 250 mL of the mixture is administered. In some aspects, about 500 mL of the mixture is administered.

[0011] In some aspects, the target fixed potency of a composition comprising the mixture is > 640 by HAI. In some aspects, the target fixed potency of a composition comprising the mixture is > 1280 by HAI. In some aspects, the mixture comprises a target fixed potency of 576,000 HAI or the MN equivalent. In some aspects, the target fixed potency of a composition comprising the mixture is > 1 :640 by HAI. In some aspects, the target fixed potency dose of the composition is 576000 HAI or the MN equivalent. In some aspects, the potency dosed is targeted to increase circulating anti-influenza antibody levels >1 :40. In some aspects, the potency is targeted to > 1 :640 by HAI to increase circulating anti-influenza antibody levels >1:40. In some aspects, administration increases circulating anti-influenza antibody levels in the patient >1 :40. In some aspects, the mixture comprising a target fixed potency of > 288, 000 by HAI is administered to the patient. In some aspects > 144, 000 by HAI is administered to the patient.

[0012] In some aspects, the mixture comprises immunoglobulin G (IgG) or antigen binding fragments thereof. In some aspects, the mixture comprises 31.5 g of IgG protein. In some aspects, the mixture comprises 15.8 g of IgG protein.

[0013] In some aspects, the mixture comprises F(ab’)2 and/or F(ab’)2-related immune globulin fragments. In some aspects, the mixture comprises F(ab’)2 immune globulin fragments.

[0014] In some aspects, the mixture comprises a purified gamma globulin (IgG) fraction of human plasma.

[0015] In some aspects, the composition is a liquid. In some aspects, the composition is a filtered sterile solution. In some aspects, the mixture was purified by anion-exchange column chromatography. In some aspects, the mixture was purified by cation-exchange chromatography. In some aspects, the mixture was obtained by pepsin digestion. In some aspects, the mixture was treated to reduce procoagulation activity. In some aspects, the mixture was subjected to virus filtration.

[0016] In some aspects, the mixture is only administered once.

[0017] In some aspects, the administration increases the anti-influenza immune globulins or antigen-binding fragments thereof by at least 2-fold, by at least 3 -fold, by at least 4- fold, or by at least 5-fold. In some aspects, the administration increases the anti -influenza immune globulins or antigen-binding fragments thereof by at least 2-fold, by at least 3- fold, by at least 4-fold, or by at least 5-fold, e.g., as determined by HAI or MN

[0018] In some aspects of the methods provided herein, 31.5 g of the human anti- influenza A immune globulins or antigen-binding fragments thereof are administered to the patient. In some aspects, 15.8 g of the human anti-influenza A immune globulins or antigen-binding fragments thereof are administered to the patient.

[0019] In some aspects of the methods disclosed herein, 500 milliliters of the composition are administered to the patient. In some aspects of the methods disclosed herein, 450 milliliters of the composition are administered to the patient. In some aspects of the methods disclosed herein, 225 milliliters of the composition are administered to the patient.

[0020] In some aspects of the methods disclosed herein, the composition comprises immune globulins or antigen-binding fragments to seasonal influenza A virus strains.

[0021] In some aspects, the administration of the composition increases circulating anti influenza antibody levels in the patient >1 :40 by HAI. In some aspects, the composition has a purity of > 96% human IgG.

[0022] In some aspects, provided herein is a composition comprising a mixture of human anti-influenza A immune globulins or antigen-binding fragments thereof for use in treating an influenza A infection in a human patient, wherein the composition comprises 31.5 g IgG protein > 288, 000 by HAI.

[0023] In some aspects, provided herein is a composition comprising a mixture of human anti-influenza A immune globulins or antigen-binding fragments thereof for use in treating an influenza A infection in a human patient, wherein the composition comprises 15.8 g IgG protein > 144, 000 by HAI. In some aspects, the composition is formulated for intravenous infusion. In some aspects, the composition has a purity of > 96% human IgG.

[0024] In some aspects, provided herein is a composition comprising a mixture of human anti-influenza A immune globulins or antigen-binding fragments thereof for use in treating an influenza A infection in a human patient according to the methods disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

[0025] FIG. 1 shows a flow diagram of a Phase 2 study using FLU-IGIV.

[0026] FIG. 2 shows the antibody concentrations measured in patients over at baseline through Day 8.

[0027] FIG. 3 shows the ordinal scale measurements in subjects on Day 8 (left) and Day 4

(right).

[0028] FIG. 4 shows the time to hospital discharge.

[0029] FIG. 5 shows the viral load in patients over time.

DETAILED DESCRIPTION

[0030] The present disclosure provides method of treating influenza using compositions comprising a mixture of anti-influenza immune globulins or antigen-binding fragments thereof.

Definitions

[0031] The terms “immune globulin,” “immunoglobulin” and “antibody” refer to a protein that recognizes and specifically binds to a target, such as a protein, polypeptide, peptide, carbohydrate, polynucleotide, lipid, or combinations of the foregoing through at least one antigen recognition site within the variable region of the immunoglobulin molecule. As used herein, the terms “immune globulin” and “antibody” encompasses intact polyclonal immune globulins, human immune globulins, and other modified immunoglobulin molecule so long as the antibodies exhibit the desired biological activity. An immune globulins can be of any the five major classes: IgA, IgD, IgE, IgG, and IgM, or subclasses (isotypes) thereof (e.g. IgGl, IgG2, IgG3, IgG4, IgAl and IgA2), based on the identity of their heavy-chain constant domains referred to as alpha, delta, epsilon, gamma, and mu, respectively. The different classes of immunoglobulins have different and well known subunit structures and three-dimensional configurations.

[0032] The term “monoclonal antibodies,” as used herein, refers to antibodies that are produced by a single clone of B-cells and bind to the same epitope. In contrast, the term “polyclonal antibodies” refers to a population of antibodies that are produced by different B-cells and bind to different epitopes of the same antigen (e.g., different epitopes of influenza).

[0033] The term “mixture” as used herein refers to a combination of at least two different components, e.g., a mixture of immune globulins refers to at least two unique immune globulins. The immune globulins can differ e.g., based on their sequence, the target to which they bind, and/or the epitope to which they bind within the target.

[0034] The term “antibody fragment” or “immune globulin fragment” refers to a portion of an intact antibody or immune globulin. An “antigen-binding fragment,” “antigen binding domain,” or “antigen-binding region,” refers to a portion of an intact antibody or immune globulin that binds to an antigen. An antigen-binding fragment can contain the antigenic determining regions of an intact antibody or immune globulin (e.g., the complementarity determining regions (CDR)). Examples of antigen-binding fragments of antibodies or immune globulins include, but are not limited to Fab, Fab', F(ab')2, and Fv fragments, linear antibodies, and single chain antibodies. An antigen-binding fragment of an antibody or immune globulin can be derived from any animal species, including humans, or can be artificially produced.

[0035] As used herein, the terms “immunospecifically binds,” “immunospecifically recognizes,” “specifically binds,” and “specifically recognizes” are analogous terms in the context of immune globulin or antigen-binding fragments thereof. These terms indicate that the immune globulin or antigen-binding fragment thereof binds to an epitope via its antigen-binding domain and that the binding entails some complementarity between the antigen binding domain and the epitope. Accordingly, for example, an antibody or immune globulin that “specifically binds” influenza can bind to influenza, but the extent of binding to an un-related virus is less than about 10% of the binding of the antibody or immune globulin to influenza, e.g., by a radioimmunoassay (RIA), enzyme-linked immunosorbent assay (ELISA), BiaCore or an octet binding assay.

[0036] Binding affinity” generally refers to the strength of the sum total of non-covalent interactions between a single binding site of a molecule (e.g., an immune globulin or antigen-binding fragment thereof) and its binding partner ( e.g ., an antigen). Unless indicated otherwise, as used herein, “binding affinity” refers to intrinsic binding affinity which reflects a 1 : 1 interaction between members of a binding pair (e.g., immune globulin or antigen-binding fragment thereof and antigen). The affinity of a molecule X for its partner Y can generally be represented by the dissociation constant (KD). Affinity can be measured and/or expressed in a number of ways known in the art, including, but not limited to, equilibrium dissociation constant (KD), and equilibrium association constant (KA). The KD is calculated from the quotient of k_0ff/k₀n, whereas KA is calculated from the quotient of k₀n/k_0ff. k₀n refers to the association rate constant of, e.g, an immune globulin or antigen-binding fragment thereof to an antigen, and k_0ff refers to the dissociation of, e.g, an immune globulin or antigen-binding fragment thereof from an antigen. The k₀n and k_0ff can be determined by techniques known to one of ordinary skill in the art, such as BIAcore^® or KinExA.

[0037] As used herein, the term “convalescent” refers a subject who has recovered from an infection or the plasma of a subject who has recovered from an infection.

[0038] As used herein, the terms “treatment,” “treating,” and the like, refer to obtaining a desired pharmacologic and/or physiologic effect. In one aspect, the effect is therapeutic, i.e., the effect partially or completely cures an infection and/or adverse symptom attributable to the infection. In one aspect, the effect is preventing an increase in severity of an infection and/or adverse symptom attributable to the infection.

[0039] A “therapeutically effective amount” refers to an amount effective, at dosages and for periods of time necessary, to achieve a desired therapeutic result (e.g., treatment of an infection).

[0040] The terms “administer”, “administering”, “administration”, and the like, as used herein, refer to methods that can be used to enable delivery of a composition (e.g., a therapeutic composition comprising a mixture of anti-influenza immune globulins and/or antigen-binding fragments thereof) to the desired site of biological action (e.g., intravenous administration). Administration techniques that can be employed with the agents and methods described herein are found in e.g, Goodman and Gilman, The Pharmacological Basis of Therapeutics, current edition, Pergamon; and Remington’s, Pharmaceutical Sciences, current edition, Mack Publishing Co., Easton, Pa.

[0041] As used herein, the terms “subject” and “patient” are used interchangeably. The subject can be an animal. In some aspects, the subject is a mammal such as a non-human animal ( e.g ., cow, pig, horse, cat, dog, rat, mouse, monkey or other primate, etc.). In some aspects, the subject is a human.

[0042] As used herein, the term “increasing the level of anti-influenza antibodies in a subject” can be used interchangeably with the term “increasing the concentration of anti- influenza antibodies in a subject.”

[0043] As used in the present disclosure and claims, the singular forms "a," "an," and

"the" include plural forms unless the context clearly dictates otherwise.

[0044] It is understood that wherever aspects are described herein with the language

“comprising,” otherwise analogous aspects described in terms of “consisting of’ and/or “consisting essentially of’ are also provided. In this disclosure, "comprises," "comprising," "containing" and "having" and the like can mean "includes," "including," and the like; "consisting essentially of' or "consists essentially" are open-ended, allowing for the presence of more than that which is recited so long as basic or novel characteristics of that which is recited is not changed by the presence of more than that which is recited, but excludes prior art aspects.

[0045] Unless specifically stated or obvious from context, as used herein, the term "or" is understood to be inclusive. The term "and/or" as used in a phrase such as "A and/or B" herein is intended to include both "A and B," "A or B," "A," and "B." Likewise, the term "and/or" as used in a phrase such as "A, B, and/or C" is intended to encompass each of the following aspects: A, B, and C; A, B, or C; A or C; A or B; B or C; A and C; A and B; B and C; A (alone); B (alone); and C (alone).

[0046] As used herein, the terms “about” and “approximately,” when used to modify a numeric value or numeric range, indicate that deviations of up to 10% above and down to 10% below the value or range remain within the intended meaning of the recited value or range. It is understood that wherever aspects are described herein with the language “about” or “approximately” a numeric value or range, otherwise analogous aspects referring to the specific numeric value or range (without “about”) are also provided

[0047] Any compositions or methods provided herein can be combined with one or more of any of the other compositions and methods provided herein. I. Compositions Comprising Immune Globulins and/or Antigen-Binding

Fragments Thereof

[0048] As provided herein, a composition (e.g., a therapeutic composition composition) can comprise a mixture of anti-influenza immune globulins or antigen-binding fragments thereof.

[0049] Such mixtures can be capable of neutralizing influenza, e.g., influenza A. Such mixtures can have a high neutralizing titer against influenza, e.g., influenza A. Such mixtures can have a neutralizing titer against influenza, e.g., influenza A that is sufficient to be effective for treatment. Assays for neutralizing influenza are known in the art and have been described, for example, in Li Z. et al., Archives of Virology 156: 1803 (2011); Yamoyoshi, S. et al., J. Clin. Virol. 108: 105-111 (2018); and/or Teferedegne, B. et al., PLoS One S(2):e56023 (2013). For example, such assays can comprise incubating the mixture (e.g., optionally serial dilutions of the mixture) with influenza (e.g., at 100 TCID50 (50% tissue culture infectious dose)). A control and a reference standard can also be incubated with influenza (e.g., at 100 TCID50 (50% tissue culture infectious dose)).

The influenza can be e.g., H1N1 or H3N2. The incubation can be e.g., for about 2 hours. The incubation can be e.g., at about 37°C. The incubation can be e.g., for about 2 hours at about 37°C. The incubated mixture and influenza can be added to cells that are capable of being infected by influenza, e.g., MDCK cells (e.g., TPCK-trypsin pre-treated MDCK cells) and further incubated. This incubation can be e.g., for about 1 hour. This incubation can be e.g., at about 37°C. This incubation can be e.g., for about 1 hour at about 37°C. The cells can then be washed to remove the supernatant and virus and then further incubated in cell culture medium. This incubation can be e.g., for about 16 hours. This incubation can be e.g., for about 18 hours or for about 22 hours. This incubation can be e.g., at about 37°C. This incubation can be e.g., for about 16 hours at about 37°C.

This incubation can be e.g., for about 16 hours at about 37°C with 5% C02. After this incubation there can be a cell fixation step. The amount of influenza infection of the cells can then be detected and compared, e.g., to the amount of influenza infection of the cells in the absence of the mixture. The amount of influenza infection can also be compared to the reference standard IgG material.

[0050] In some aspects, the anti-influenza immune globulins or antigen-binding fragments thereof are human immune globulins or antigen-binding fragments thereof.

The human immune globulins or antigen-binding fragments thereof can be derived from human plasma. The plasma can be, for example, convalescent human plasma. The plasma can be, for example from donors who have recovered from the seasonal flu. The plasma can be, for example from donors who received the seasonal flu (influenza) shot. The plasma can be from a combination of donors who have recovered from the seasonal flu (influenza) and donors who received the seasonal flu (influenza) shot.

[0051] In some aspects, the anti-influenza immune globulins or antigen-binding fragments thereof can be derived from non-human mammals. In some aspects the anti- influenza immune globulins or antigen-binding fragments thereof can be derived from horses. In some aspects the anti-influenza immune globulins or antigen-binding fragments thereof can be derived from cows.

[0052] The antigen-binding fragments can be, e.g., F(ab’)2 and F (ah’ )2 -related immune globulin fragments. Such fragments can be generated e.g., by pepsin digestion.

[0053] The immune globulins or antigen-binding fragments thereof can be IgG immune globulins or fragments.

[0054] A composition (e.g., a therapeutic composition) comprising a mixture of anti- influenza immune globulins or antigen-binding fragments thereof can be a liquid. Such a liquid can comprise 65 milligrams of protein per milliliter (mg/mL).

[0055] A composition (e.g., a therapeutic composition) comprising a mixture of anti- influenza immune globulins or antigen-binding fragments thereof can be a filtered sterile solution. Such compositions can be formulated for intravenous administration. In some aspects, the mixture can comprise 31.5 g of IgG protein. In some aspects, the mixture can comprise 15.8 g of IgG protein.

[0056] Compositions (e.g., a therapeutic compositions) comprising a mixture of anti- influenza immune globulins or antigen-binding fragments thereof can be made using any method known in the art and/or provided herein.

[0057] Methods of making such compositions can comprise purifying the mixture of anti- influenza immune globulins or antigen-binding fragments thereof (e.g., from plasma).

The purification can comprise anion-exchange column chromatography and/or cation- exchange purification.

[0058] Methods of making such compositions can comprise subjecting a mixture of immune globulins or antigen-binding fragments thereof (e.g., from plasma) to viral filtration. [0059] Methods of making such compositions can comprise digesting a mixture of immune globulins or antigen-binding fragments thereof (e.g., from plasma) to form F(ab’)2 and F(ab’)2-related immune globulin antigen-binding fragments.

II. Methods of Using Compositions Comprising Immune Globulins and/or Antigen-Binding Fragments Thereof

[0060] Provided herein are methods of using compositions comprising a mixture of anti influenza immune globulins or antigen-binding fragments thereof. The compositions can be used therapeutically, e.g., to treat an influenza A infection in a patient (e.g., a human patient).

[0061] The influenza A can be subtype H3N2. The influenza A can be subtype HINT

[0062] The influenza A patient can be hospitalized. The patient can be in an intensive care unit (ICU). The influenza A infection can be a seasonal infection. The influenza A infection can be a seasonal infection in a hospitalized patient or a patient in an ICU. In some aspects, the patient was admitted to the hospital through the emergency room (ER). In some aspects, the patient is in the observation unit. In some aspects, the patient is planned to be hospitalized in the opinion of the attending physician. In some aspects, the patient has severe influenza A. In some aspects, the patient is hospitalized with serious illness caused by influenza A infection. In some aspects, the patient is hospitalized with severe influenza. In severe influenza cases, hospitalization can occur due to breathing difficulties and pneumonia or other complications, which can be fatal. Complicated or severe influenza cases occur in those with progressive infection including central nervous system involvement, secondary complications, exacerbation of underlying chronic diseases, or development of concurrent comorbidities that require hospitalization.

[0063] The methods described herein provide advantages over the standard of care treatment of influenza A. Advantages associated with the compositions comprising a mixture of anti-influenza immune globulins or antigen-binding fragments thereof described herein include, but are not limited to: reducing the severity and duration for the course of illness of influenza A, and/or a reduced need for supportive measures e.g., stabilized oxygen levels etc.

[0064] The methods described herein, while not bound by theory, are believed to exert their effects by increasing the level of anti-influenza (e.g., influenza A) antibodies or antigen-binding fragments thereof in a subject. In some aspects, the level of anti -influenza (e.g., influenza A) antibodies or antigen-binding fragments thereof in a subject is increased as compared to the natural level of anti -influenza (e.g., influenza A) antibodies or antigen-binding fragments in the subject. In some aspects, as compared to the natural level of anti- anti -influenza (e.g., influenza A) antibodies or antigen-binding fragments thereof in a subject, the level of anti-influenza (e.g., influenza A) antibodies or antigen binding fragments thereof is increased about 2 times, about 3 times, about 4 times, or about 5 times, the natural levels of anti-influenza (e.g., influenza A) antibodies or antigen-binding fragments thereof in a subject. In some aspects, the level of anti- influenza (e.g., influenza A) antibodies or antigen-binding fragments thereof increases within 2 days of administration of the mixture of anti-influenza immune globulins or antigen-binding fragments thereof.

[0065] In some aspects, provided herein are methods of treating influenza (e.g., influenza A) in a patient, e.g., a human patient. In some aspects, the methods of treating influenza (e.g., influenza A) in a patient provided herein comprise administering to a patient an effective amount of a composition comprising a mixture of anti-influenza immune globulins or antigen-binding fragments thereof. Suitable mixtures of immune globulins or antigen-binding fragments thereof are described elsewhere herein and can be administered, e.g., intravenously.

[0066] In some aspects, provided herein are methods of treating influenza (e.g., influenza A) in a patient comprising administering to the patient an effective amount of a composition comprising a mixture of anti-influenza immune globulins or antigen-binding fragments thereof, wherein the mixture comprises 65 milligrams of protein per milliliter (65 mg/mL).

[0067] In some aspects, provided herein are methods of treating influenza (e.g., influenza A) in a patient comprising administering to the patient about 450 mL of a composition comprising a mixture of anti-influenza immune globulins or antigen-binding fragments thereof, e.g. wherein the mixture comprises 65 mg/mL. In some aspects, provided herein are methods of treating influenza (e.g., influenza A) in a patient comprising administering to the patient about 225 mL of a composition comprising a mixture of anti-influenza immune globulins or antigen-binding fragments thereof, e.g. wherein the mixture comprises 65 mg/mL. In some aspects, provided herein are methods of treating influenza (e.g., influenza A) in a patient comprising administering to the patient 250 mL or less of a composition comprising a mixture of anti-influenza immune globulins or antigen-binding fragments thereof, e.g. wherein the mixture comprises 65 mg/mL. In some aspects, the mixture is only administered once.

[0068] In some aspects, the target fixed potency dose of the composition is 576000 HAI or the MN equivalent. In some aspects, the potency of the composition is targeted to >

1 :640 by HAI. In some aspects, the potency dosed is targeted to increase circulating anti- influenza antibody levels >1 :40. In some aspects, the potency is targeted to > 1 :640 by HAI to increase circulating anti-influenza antibody levels >1:40. In some aspects, administration increases circulating anti -influenza antibody levels in the patient >1 :40. In some aspects, > 288, 000 by HAI is administered to the patient. In some aspects > 144, 000 by HAI is administered to the patient.

[0069] In some aspects, the methods provided herein decrease the patient’s ordinal scale score, e.g., within 4 days. In some aspects, the methods provided herein decreases the patient’s ordinal scale score by at least 1 point, e.g., within 4 days. In some aspects, the methods provided herein decreases the patient’s ordinal scale score by at least 2 points, e.g., within 4 days.

[0070] In some aspects, the methods provided herein decrease the duration of the patient’s hospital stay. In some aspects, the methods provided herein decrease the duration of the patient’s hospital stay by at least 1 day. In some aspects, the methods provided herein decrease the duration of the patient’s hospital stay by at least 2 days. In some aspects, the patient is released from the hospital within 4 days of the administration of a mixture of anti-influenza immune globulins or antigen-binding fragments thereof. In some aspects, the patient is released from the hospital within 3 days of the administration of a mixture of anti-influenza immune globulins or antigen-binding fragments thereof. In some aspects, the patient is released from the hospital within 2 days of the administration of a mixture of anti-influenza immune globulins or antigen-binding fragments thereof. In some aspects, the patient is released from the hospital within 1 day of the administration of a mixture of anti-influenza immune globulins or antigen-binding fragments thereof.

[0071] In some aspects, the methods provided herein decrease the amount of time the patient needs supplemental oxygen.

[0072] In some aspects, the methods provided herein increase hemagglutination inhibition (HAI) in the patient. In some aspects, the methods increase HAI in the patient within 2 days of the administration. In some aspects, the administration increases anti- influenza antibody levels as measured by HAI. In some aspects, the administration increases HAI titers in the patient within 2 days of the administration.

[0073] In some aspects, the methods provided herein increase microneutralization (MN) in the patient. In some aspects, the methods increase MN in the patient within 2 days of the administration.

[0074] In some aspects, the methods provided herein increase the ability to detect virus- specific neutralizing antibodies to influenza viruses in a microneutralization assay. In some aspects, the administration increases microneutralization (MN) titers in the patient. In some aspects, the administration increases MN titers in the patient within 2 days of the administration.

[0075] In some aspects, provide herein are methods of treating influenza (e.g., influenza

A) in a patient, wherein the patient has at least one respiratory symptom and/or at least one constitutional symptom. Respiratory symptoms include, for example, a cough, sore throat, and/or nasal congestion. Constitutional symptoms include, for example, headache, myalgia, feverishness, and/or fatigue. In some aspects of the methods provided herein, the administration of the mixture of mixture of anti-influenza immune globulins or antigen-binding fragments thereof occurs within 6 days of the onset of symptoms. In some aspects, the administration of the mixture of anti-influenza immune globulins or antigen-binding fragments thereof occurs within 5 days of onset of illness. In some aspects, the administration of the mixture of anti-influenza immune globulins or antigen binding fragments thereof occurs within 4 days of onset of illness. In some aspects, the administration of the mixture of anti-influenza immune globulins or antigen-binding fragments thereof occurs within 3 days of onset of illness. In some aspects, the administration of the mixture of anti-influenza immune globulins or antigen-binding fragments thereof occurs within 2 days of onset of illness. In some aspects, the administration of the mixture of anti-influenza immune globulins or antigen-binding fragments thereof occurs within 1 day of onset of illness.

[0076] In some aspects, provide herein are methods of treating influenza (e.g., influenza

A) in a patient, wherein the patient has a National Early Warning Score (NEW) score of at least 3 (see Royal College of Physicians. National Early Warning Score (NEWS): Standardising the assessment of acute illness severity in the NHS. Report of a working party. London: RCP, 2012, which is incorporated by reference herein). [0077] In some aspects, provided herein are methods of treating influenza (e.g., influenza

A) in a patient comprising administering to the patient a mixture of anti-influenza immune globulins or antigen-binding fragments thereof and an anti-viral agent. In some aspects the mixture is administered only once and/or the anti-viral agent is administered for at least 5 days. Anti-viral agents include, for example, neuraminidase inhibitors such as oseltamivir phosphate (Tamiflu^®), zanamivir(Relenza^®), and peramivir (Rapivab^®). Anti-viral agents also include, for example, cap-dependent endonuclease inhibitors such as baloxavir marboxil (Xofluza^®).

[0078] In some aspects, the method further comprises administering oseltamivir. In some aspects, the oseltamivir is administered for at least five days. In some aspects, the oseltamivir is administered for 5 days at a dose of 75 mg/day.

Examples

[0079] The examples in this Examples Section are offered by way of illustration, and not by way of limitation.

Example 1: FLU-IGIV

[0080] FLU-IGIV is for the treatment of serious influenza A infection in hospitalized patients. Plasma is collected and pooled from donors who have recovered from the seasonal flu (influenza) or who have had the seasonal flu (influenza) shot. The pooling achieves consistent levels of target antibodies or fragments thereof, which can include antibodies and fragments against a range of influenza antigens. Antibodies and fragments are then purified, including steps for virus removal, in order to manufacture concentrated, uniform doses for administration to patients. The resulting sterile, liquid, anti-influenza immune globulin product for intravenous administration is called FLU-IGIV.

[0081] The FLU-IGIV formulation is for administration in a fixed volume dose. The

FLU-IGIV is formulated in a high dose and a low dose, which correspond to target potencies, as follows:

• High Dose 31.5 g IgG protein > 288, 000 by HAI

• Low Dose 15.8 g IgG protein > 144, 000 by HAI Example 2: Treatment of Influenza Using FLU-IGIV

[0082] A randomized, double-blind, placebo-controlled Phase 2 clinical trial was conducted to demonstrate the efficacy of FLU-IGIV in treating influenza A in human patients. The design of the study is shown in FIG. 1.

Patients

[0083] All participants in the study were at least 18 years of age and had a locally determined positive influenza A infection (Rapid Antigen (Ag) Test or PCR) from a specimen obtained within two days prior to randomization. All participants had an onset of symptoms < 6 days before randomization, defined as when the patient first experienced at least one respiratory symptom or fever. All participants were hospitalized or in an observation unit with influenza, with anticipated hospitalization for more than 24 hours. All participants were experiencing > 1 respiratory symptom (e.g., cough, sore throat, nasal congestion) and > 1 constitutional symptom (e.g., headache, myalgia, feverishness, fatigue). In addition, all participants had a National Early Warning Score (NEW score) of > 3 at screen.

[0084] In the study, 65 subjects were randomized, and 53 subjects completed the study.

Out of the randomized subjects, 5 were not dosed, 19 received 450 mL dose (“high dose”) of FLU-IGIV, 19 received 225 mL dose (“low dose”) of FLU-IGIV, and 22 received placebo (500 mL) saline. Both the high dose and the low dose of FLU-IGIV were administered in total volumes of 500 mL. All dosed participants received a single infusion administered over approximately 3 hours on Day 1. All dosed participants also received standard of care antiviral treatment for influenza.

[0085] The majority (95%) of the subjects were in the United States. The placebo group had an older median age, and the high dose group had a higher median weight and BMI.

[0086] At baseline, 40% of patients were admitted to the general ward of a hospital, 40% of the patients were admitted to an Emergency Room (ER), and 20% were admitted to an Intensive Care Unit/other hospital unit. More of the high dose patients presented in an ER (47%) or in an ICU (26%) at baseline.

[0087] NEW scores, which measure respiratory rate, heart rate, temperature, oxygenation, blood pressure, and level of consciousness, were measured in patients at baseline. At screening and by baseline, 28% of patients had a NEW Score of less than 3, 18% had a NEW score equal to 3, and 53% had a NEW score of greater than 3. More of the patients who received placebo had a NEW score of less than 3 (36%).

[0088] PCR assays to test influenza strains were also performed at baseline. 87% of patients were positive. 42% of patients were A/Hl/unspecified, and 45% were A/H3, of which 23% had Hong Kong strain, and 20% had A/H3/unspecified. More of high dose patients presented with Hl/unspecified (65%).

[0089] The baseline demographics of the study participants are shown below in Table 1.

Table 1: FLU-IGIV in patients hospitalized with influenza A

Safety and Pharmacokinetics

[0090] The mean ordinal scales in the FLU-IGIV groups on Day 2 (one day post treatment) did not worsen. All subjects received the full 500 mL; no adverse event (AE) led to incomplete dose or early withdrawn. No related serious adverse events (SAEs) were observed. Related adverse events (AEs) occurred in 6 subjects: two in the high dose group, and 4 in the low dose group. There were balanced AEs between the groups: 10 in the high dose group (53%), 12 in the low dose group (63%), and 11 in the placebo group (50%).

[0091] Liver enzymes were also observed as an indicator of safety. The results, which are provided in Table 2, demonstrate that FLU-IGIV was safe and well-tolerated with a safety profile consistent with other human immunoglobulin products with no significant differences in adverse events or severity related to dose.

Table 2: Safety Observation for Liver Enzyme Elevation Post-Dose

[0092] Antibody concentrations in patients were measured at baseline, after infusion on

Day 1, and on Days 2, 3, and 8. The results are shown in FIG. 2.

[0093] The overall safety data was favorable, and dose-dependent increase by hemagglutination inhibition (HAI) and microneutralization (MN) were observed in the first 2 days. MN data was highly variable. In particular, this data demonstrates that the pharmacokinetic profile was approximately dose-dependent, with a linear increase in anti- influenza antibodies by both HAI and MN. The parameters were discernable only up until 48 hours post-dose due to the influence of endogenous antibody production contributing to later pharmacokinetic parameters.

[0094] The Adverse drug reactions (ADRs) according to severity and System Organ

Class (SOC) are presented in Table 3. Additional safety results are presented in Table 4. Table 3: Summary of Adverse Drug Reactions by System Organ Class, Preferred Term and Severity

Table 4: Safety Results

SAE = severe adverse event

AE = adverse event

Related AEs = related adverse events

AESIs = adverse events of special interest [0095] PK was assessed in all subjects by both HAI and MN. PK parameters are expressed for the A/Califomia/07/2009 (H1N1) strain. The PK parameters by HAI are provided below in Table 5.

Table 5. Pharmacokinetic Parameters by HAI

[0096] The PK was dose-dependent and linear up to 48 hours post-dose.

Efficacy

[0097] Ordinal scale scores were assessed on Days 4 and 8. The Ordinal scale is provided in Tables 6 and 7 below, and the results are shown in FIG. 3. Although no difference was observed at Day 8, a difference was observed at Day 4. The ordinal scale status at Day 4 demonstrated dose-related efficacy with the FLU-IGIV high-dose group displaying the most improvement on the Ordinal Scale relative to those in the FLU-IGIV low-dose group and the placebo group.

Table 6: Secondary Endpoint: clinical status was measured at Day 8 by an ordinal scale of six mutually exclusive categories

Table 7. Ordinal Scale

[0098] The time until hospital discharge was also determined. The results shown in FIG. 4 demonstrate the efficacy of the FLU-IGIV treatment. The dose response vs. treatment effect is summarized in Table 8. There were 13 patients in the ICU and 44 patients on oxygen. More detailed viral load data is provided in FIG. 5.

Table 8: Dose Response vs. Treatment Effect

*Not formal endpoints [0099] The Day 4 ordinal scores, durations of hospitalization, and supplementation of oxygen demonstrated treatment dose trends

* * *

[0100] All references ( e.g ., publications or patents or patent applications) cited herein are incorporated herein by reference in their entirety and for all purposes to the same extent as if each individual reference (e.g., publication or patent or patent application) was specifically and individually indicated to be incorporated by reference in its entirety for all purposes

Claims

WHAT IS CLAIMED IS:

1. A method of treating an influenza A infection in a human patient, the method comprising administering to the patient an effective amount of a composition comprising a mixture of human anti-influenza A immune globulins or antigen-binding fragments thereof.

2. The method of claim 1, wherein the administration decreases the patient’s ordinal scale score, optionally wherein the decrease is within 4 days or within 8 days.

3. The method of claim 1 or 2, wherein the administration decreases the duration of the patient’s hospital stay.

4. The method of any one of claims 1-3, wherein the administration decreases the amount of time the patient needs supplemental oxygen.

5. The method of any one of claims 1-4, wherein the administration reduces the severity and duration of the course of illness in the patient.

6. The method of any one of claims 1-5, wherein the administration improves the standard of care treatment for the patient.

7. claims 1-6, wherein the administration prevents death of the patient.

8. The method of any one of claims 1-7, wherein the administration increases anti-influenza antibody levels as measured by HAI in the patient, optionally wherein the administration increases anti-influenza antibody levels as measured by HAI within 2 days of the administration.

9. The method of any one of claims 1-8, wherein the administration increases anti-influenza antibody levels by microneutralization (MN) in the patient, optionally wherein the administration increases anti-influenza antibody levels by MN in the patient within 2 days of the administration.

10. The method of any one of claims 1-9, wherein the influenza A infection is a seasonal influenza A infection.

11. The method of any one of claims 1-10, wherein the influenza subtype is H3N2.

12. The method of any one of claims 1-10, wherein the influenza subtype is H1N1.

13. The method of any one of claims 1-12, wherein the patient is hospitalized.

14. The method of any one of claims 1-13, wherein the patient is in an intensive care unit

(ICU).

15. The method of any one of claims 1-13, wherein the patient was admitted to the hospital through the emergency room (ER).

16. The method of any one of claims 1-15, wherein the patient has severe influenza A.

17. The method of any one of claims 1-15, wherein the patient is hospitalized with serious illness caused by influenza A infection.

18. The method of any one of claims 1-17, wherein the patient is hospitalized with severe influenza.

19. The method of any one of claims 1-18, wherein the mixture is administered intravenously.

20. The method of any one of claims 1-19, wherein the mixture is administered within 1 to 6 days of onset of illness.

21. The method of any one of claims 1-20, further comprising administering an anti -viral drug, optionally wherein said anti-viral is oseltamivir phosphate, zanamivir, peramivir, or baloxavir marboxil.

22. The method of claim 21, wherein the anti-viral drug is administered for at least two, at least three, at least four, or at least five days.

23. The method of claim 21 or 22, wherein said anti -viral is oseltamivir phosphate.

24. The method of claim 23 wherein the oseltamivir is administered for 5 days.

25. The method of claim 23 or 24 wherein the oseltamivir is administered for 5 days at a dose of 75 mg/day.

26. The method of any one of claims 1-25, wherein the mixture comprises 65 milligrams (mg) of protein /milliliter (mL).

27. The method of any one of claims 1-26, wherein 450 mL of the mixture is administered.

28. The method of any one of claims 1-26, wherein 250 mL or less of the mixture is administered, optionally wherein 225 mL of the mixture is administered.

29. The method of any one of claims 1-28, wherein the target fixed potency of the composition is 576000 HAI or the MN equivalent.

30. The method of any one of claims 1-28, wherein the target potency of the composition is > 1:640 by HAI.

31. The method of any one of claims 1-28, wherein > 288, 000 by HAI is administered to the patient.

32. The method of any one of claims 1-28, wherein > 144, 000 by HAI is administered to the patient.

33. The method of any one of claims 1-32, wherein the mixture comprises immunoglobulin G (IgG) or antigen-binding fragments thereof.

34. The method of claim 33, wherein the mixture comprises 31.5 g of IgG protein.

35. The method of claim 33, wherein the mixture comprises 15.8 g of IgG protein.

36. The method of any one of claims 1-35, wherein the mixture comprises F(ab’)2 and/or F(ab’)2-related immune globulin fragments.

37. The method of any one of claims 1-36, wherein the mixture comprises a purified gamma globulin (IgG) fraction of human plasma.

38. The method of any one of claims 1-37 wherein the composition is a liquid.

39. The method of any one of claims 1-38, wherein the composition is a filtered sterile solution.

40. The method of any one of claims 1-39, wherein the mixture was purified by anion- exchange column chromatography.

41. The method of any one of claims 1-39, wherein the mixture was purified by cation- exchange chromatography.

42. The method of any one of claims 1-41, wherein the mixture was obtained by pepsin digestion.

43. The method of any one of claims 1-42, wherein the mixture was treated to reduce procoagulation activity.

44. The method of any one of claims 1-43, wherein the mixture was subjected to virus filtration.

45. The method of any one of claims 1-44, wherein the mixture is only administered once.

46. The method of any one of claims 1-45, wherein the administration increases the anti influenza immune globulins or antigen-binding fragments thereof by at least 2-fold, by at least 3-fold, by at least 4-fold, or by at least 5-fold, as determined by HAI or MN.

47. The method of any one of claims 1-46, wherein the administration of a single dose is efficacious against multiple influenza A strains across multiple seasons.

48. The method of any one of claims 1-47, wherein 31.5 g of the human anti-influenza A immune globulins or antigen-binding fragments thereof are administered to the patient.

49. The method of any one of claims 1-47, wherein 15.8 g of the human anti-influenza A immune globulins or antigen-binding fragments thereof are administered to the patient.

50. The method of any one of claims 1-49, wherein 500 milliliters of the composition are administered to the patient.

51. The method of any one of claims 1-49, wherein the composition comprises immune globulins or antigen-binding fragments to seasonal influenza A virus strains.

52. The method of any one of claims 1-49, wherein the administration increases circulating anti-influenza antibody levels in the patient >1 :40.

53. The method of any one of claims 1-52, wherein the composition has a purity of > 96% human IgG.

54. A composition comprising a mixture of human anti-influenza A immune globulins or antigen-binding fragments thereof for use in treating an influenza A infection in a human patient, wherein the composition comprises 31.5 g IgG protein > 288, 000 by HAI.

55. A composition comprising a mixture of human anti-influenza A immune globulins or antigen-binding fragments thereof for use in treating an influenza A infection in a human patient, wherein the composition comprises 15.8 g IgG protein > 144, 000 by HAI.

56. The composition of claim 54 or 55, wherein the composition is formulated for intravenous infusion.

57. The composition of any one of claims 54-56, wherein the composition has a purity of > 96% human IgG.

58. A composition comprising a mixture of human anti-influenza A immune globulins or antigen-binding fragments thereof for use in treating an influenza A infection in a human patient according to the method of any one of claims 1-53.