WO2008065138A1

WO2008065138A1 - Novel insulin crystal and method for preparing the crystal

Info

Publication number: WO2008065138A1
Application number: PCT/EP2007/062946
Authority: WO
Inventors: Mathias Norrman; Gerd Schluckebier; Jes Kristian Jacobsen
Original assignee: Novo Nordisk A/S
Priority date: 2006-11-29
Filing date: 2007-11-28
Publication date: 2008-06-05

Abstract

The invention concerns a crystal comprising insulin characterised in the crystal being grown in the presence of a chaotropic agent provided that the crystal is not grown in the presence of urea and a process for preparing the crystal.

Description

NOVEL INSULIN CRYSTAL AND METHOD FOR PREPARING THE CRYSTAL

FIELD OF THE INVENTION

The present invention relates to a novel insulin crystal, which can be used for the treatment of patients suffering from diabetes or hyperglycaemia. The invention also relates to methods of providing such crystals, to pharmaceutical compositions containing them, to methods of treating diabetes and hyperglycaemia using the insulin crystals and to the use of such insulin crystals in the treatment of diabetes and hyperglycaemia.

BACKGROUND OF THE INVENTION

The therapeutic hormone insulin is a small protein having influence on the blood glucose level. It is daily used in the medical treatment of diabetes by millions of people. Diabetes is a chronic disease cause by absolute or relative deficiency of insulin and insulin resistance, which results in high blood glucose levels (hyperglycemia) leading to long-term complications.

Currently, the treatment of diabetes, both type 1 diabetes and type 2 diabetes, relies to an increasing extent on the so-called intensive insulin treatment. According to this regimen, the patients are treated with multiple daily insulin injections comprising one or two daily injections of long acting insulin to cover the basal insulin requirement supplemented by bolus injections of rapid acting insulin to cover the insulin requirement related to meals.

The primary administration route is by subcutaneous injections of microcrystals or mixtures of microcrystals and amorphous protein. After subcutaneous injection, the insulin crystals dissolve slowly, thus leading to a slow intermediate release of insulin into the blood stream. Ever since the biological function of insulin was discovered in the 1920s, the mole- cule has been widely characterized both biophysically and structurally. The crystal log raphic structure was one of the first determined protein structures. It has since then been crystallized in a number of different forms of which the most common belong to the monoclinic, rhombohedral, cubic and tetragonal crystal forms. The type, size and morphology of the crystals determine how fast insulin is released, which is why crystallization of insulin has been studied extensively. Alternative administration routes exist and are at present a rapidly expanding research field. Insulin microcrystals may be well suited for other delivery methods, such as pulmonary delivery or sustained release formulations. A crystal structure is a unique arrangement of atoms in a crystal. A crystal structure is composed of a unit cell, a set of atoms arranged in a particular way; which is periodically repeated in three dimensions on a lattice. The spacing between unit cells in various directions is called its lattice parameters or unit cell constants. The symmetry properties of the crystal are embodied in its space group. A crystal's structure and symmetry play a role in determining many of its physical properties and can be measured by X-ray diffraction methods. A more detailed introduction is given in Fundamentals of Crystallography, edited by C. Gi- acovazzo, Oxford University Press 1992.

The molecule of insulin consists of two chains, A and B, with 21 and 30 residues re- spectively. The A chain is built up by two helical fragments separated by a short elongated part linked to one of the helices by an intra-chain disulfide bond. Two additional disulfide bonds link the A chain to the larger B chain. In the biologically active form insulin exists as a monomer in which the B chain contains a central helical region flanked by two elongated parts. In the presence of divalent ions like zinc, the monomers assemble into hexamers, where each of the two central zinc ions is coordinated by three histidine residues.

The first stable protracted preparation of insulin, the NPH (Neutral Protamine Hage- dorn) was introduced in 1946. The insulin-zinc solution was co-crystallized with the basic peptide, protamine, which consists mainly of arginine residues. This polypeptide reduces insulin solubility. Each hexamer contained two zinc atoms and approximately one protamine peptide and was crystallized at pH 7.3 in the tetragonal crystal system with space group P4₃2-|2. The commercial products Penmix30 (human insulin) and Novomix30 (ProB28Asp) consist of a mixture of soluble- and crystallized NPH insulin in the ratio of 30/70. The Prota- phan formulation consists of 100% crystals from pig insulin (ThrB30Ala). Another type of insulin formulation with an even more prolonged action profile are often re- ferred to as Lente insulins. They consist of rhombohedral crystals of space group R3 and contain hexameric insulin with two zinc atoms at the three-fold axis and one phenolic derivative per monomer. The commercial products Ultratard and Ultralente consist of 100% crystalline human insulin. A third type, the Lente product, consists of one third amorphous pig insulin and two thirds crystalline bovine insulin. Twelve different micro-crystalline insulin formulations were investigated by X-ray powder diffraction by Norrman et al (Characterization of insulin microcrystals using powder diffraction and multivariate data analysis, J. Appl. Cryst. (2006) 39, 391-400). One of the insulin formulations was found to have a novel orthorhombic crystal structure. This insulin was obtained in the presence of urea. SUMMARY OF THE INVENTION

The present invention is based on the recognition that a crystal comprising insulin which has been grown without the presence of urea but in the presence of a chaotropic agent can be used for the treatment of patients suffering from diabetes type 1 , diabetes type 2 or hyperglycaemia.

DEFINITIONS

A "Chaotropic" agent" is a molecule or an ion which causes the tertiary structure of macromolecules to be disrupted; in particular, those formed by nonbonding forces such as hydrogen bonding, Van der Waals interactions, and the hydrophobic effect. Examples of cha- otropic agents include, but are not limited to anions, such as thiocyanate, nitrate, perchlorate; cations such as trimethylammonium or guanidinium or organic molecules such as arginine.

A "precipitant" is any substance that when added to a solution cause a precipitate to form or crystals to grow. Examples of a precipitant include, but are not limited to, alkali or alkaline earth metal salts and transition metal salts. Common counterions to the metals in- elude, but are not limited to halides, phosphates, citrates and sulfates. A precipitant can also be an alcohol (e.g. ethanol) or a polymer (such as Poly-ethylene-glycol). A precipitant may be used alone or in combination with another precipitant e.g. sodium chloride in combination with ethanol.

In crystallography, a crystal structure is a unique arrangement of atoms in a crystal. A crystal structure is composed of a unit cell, a set of atoms arranged in a particular way; which is periodically repeated in three dimensions on a lattice. The spacing between unit cells in various directions is called its lattice parameters or unit cell constants or unit cell parameters. The symmetry properties of the crystal are embodied in its space group. A crystal's structure and symmetry play a role in determining many of its physical properties. A more detailed introduction is given in Fundamentals of Crystallography, edited by C. Giaco- vazzo, Oxford University Press 1992.

The "space group" of a crystal is a mathematical description of the symmetry inherent in the structure. The word 'group' in the name comes from the mathematical notion of a group, which is used to build the set of space groups. The space group can be determined by X-ray diffraction (powder and single crystal methods) and electron diffraction. Examples of a space group are C222i or C2. All possible space groups of crystals are compiled in the International Tables for Crystallography Volume A (Ed. Theo Hahn, 5. ed, 2002, Kluwer Academic Publishers). With "lattice parameters", "unit cell constants" or "unit cell parameters" as used herein is meant the size of the unit cell, as described by the lengths of the cell edges (typically in A; iA=10^"10m) and the size of the angles between them. The lattice parameters, unit cell constants or unit cell parameters can be measured e.g. by X-ray powder diffraction. Ref- erence is given to Fundamentals of Crystallography, edited by C. Giacovazzo, Oxford University Press 1992.

With "insulin" as used herein is meant human insulin, porcine insulin or bovine insulin with disulfide bridges between CysA7 and CysB7 and between CysA20 and CysB19 and an internal disulfide bridge between CysA6 and CysA1 1 or an insulin analogue thereof. With "B1", "A1" etc. is meant the amino acid residue at position 1 in the B-chain of insulin (counted from the N-terminal end) and the amino acid residue at position 1 in the A- chain of insulin (counted from the N-terminal end), respectively. The amino acid residue in a specific position may also be denoted as e.g. PheB1 which means that the amino acid residue at position B1 is a phenylalanine residue. By "insulin analogue" as used herein is meant a polypeptide which has a molecular structure which formally can be derived from the structure of insulin, for example that of human insulin, by deleting and/or exchanging at least one amino acid residue occurring in the naturally occurring insulin and/or adding at least one amino acid residue. The added and/or exchanged amino acid residues can either be codable amino acid residues or other naturally occurring residues or purely synthetic amino acid residues The insulin analogues may be such wherein position 28 of the B chain may be modified from the natural Pro residue to one of Asp, Lys, or lie. In another aspect Lys at position B29 is modified to Pro. Also, Asn at position A21 may be modified to Ala, GIn, GIu, GIy, His, lie, Leu, Met, Ser, Thr, Trp, Tyr or VaI, in particular to GIy, Ala, Ser, or Thr and preferably to GIy. Furthermore, Asn at position B3 may be modified to Lys or Asp. Further examples of insulin analogues are des(B30) human insulin; des(B30) human insulin analogues; insulin analogues wherein PheB1 has been deleted; insulin analogues wherein the A-chain and/or the B-chain have an N-terminal extension and insulin analogues wherein the A-chain and/or the B-chain have a C-terminal extension. Thus one or two Arg may be added to position B1. In aspects of the invention a maximum of 17 amino acids have been modified. In aspects of the invention a maximum of 15 amino acids have been modified. In aspects of the invention a maximum of 10 amino acids have been modified. In aspects of the invention a maximum of 8 amino acids have been modified. In aspects of the invention a maximum of 7 amino acids have been modified. In aspects of the invention a maximum of 6 amino acids have been modified. In aspects of the invention a maximum of 5 amino acids have been modified. In aspects of the invention a maximum of 4 amino acids have been modified. In aspects of the invention a maximum of 3 amino acids have been modified. In aspects of the invention a maximum of 2 amino acids have been modified. In aspects of the invention 1 amino acid has been modified.

With desB30 insulin", "desB30 human insulin" is meant insulin or an analogue thereof lacking the B30 amino acid residue. Similarly, "desB29desB30 insulin" or desB29desB30 human insulin" means a natural insulin or an analogue thereof lacking the B29 and B30 amino acid residues.

DESCRIPTION OF THE INVENTION

It has now surprisingly been found that crystals of insulin can be obtained without growing in the presence of urea, resulting in crystals which are chemically more stable.

It is an object of the present invention to provide a crystal comprising insulin. The crystal is characterised in being grown without urea and being grown in the presence of a chaotropic agent. In one aspect of the invention the crystal belongs to the space group C222i with unit cell constants of a=59 A b=220 A c=225 A α=β=γ=90°. In one aspect the crystal belongs to space group C2 with unit cell constants of a=101 A b=61 A c=63 A α=90° β=116° γ=90°. The space groups and the unit cell constants are determined by X-ray diffraction.

The crystal can be grown in the presence of various excipients such as zinc and phenolic agents. It is however important that urea is not present when the crystal is grown. Urea has been shown to be chemically reacting with insulin, thus decreasing the chemical stability of the crystal comprising insulin.

In one aspect of the inventions the crystal comprises zinc.

In one aspect the crystal also comprises a phenolic agent, which phenolic agent is selected from the group consisting of resorcinol, cresol, meta-cresol, phenol, methyl p- hydroxybenzoate and methyl 4-hydroxybenzoate.

In one aspect of the invention the chaotropic agent can be an anion, such as thiocy- anate, nitrate, perchlorate; a cation such as trimethylammonium or guanidinium or an organic molecule such as arginine. For example the chaotropic agent can be selected from the group of alkali metal salts of thiocyanate, such as sodium thiocyanate or potassium thiocyanate. The chaotropic agent can also be a mixture of two or more alkali metal salts of thiocyanate.

The crystals of the present invention are in the range of 1-50 μm, for example in the range of 1-30 μm, 1-20 μm, 1-10 μm, 1-5 μm, 1-3 μm or 2-3 μm. In one aspect of the invention at least 50% of the crystals are in the range of the range of 1-30 μm. In one aspect of the invention at least 70% of the crystals are in the range of the range of 1-30 μm. In one aspect of the in aspect of the invention at least 90% of the crystals are in the range of the range of 1-30 μm.

In one aspect of the invention at least 50% of the crystals are in the range of the range of 1-20 μm. In one aspect of the invention at least 70% of the crystals are in the range of the range of 1-20 μm. In one aspect of the in aspect of the invention at least 90% of the crystals are in the range of the range of 1-20 μm.

In one aspect of the invention at least 50% of the crystals are in the range of the range of 1-10 μm. In one aspect of the invention at least 70% of the crystals are in the range of the range of 1 -10 μm. In one aspect of the in aspect of the invention at least 90% of the crystals are in the range of the range of 1-10 μm.

In one aspect of the invention at least 50% of the crystals are in the range of the range of 1-5 μm. For example at least 50% of the crystals are in the range of 1-3 μm. In one aspect of the invention at least 70% of the crystals are in the range of the range of 1-5 μm. For example at least 70% of the crystals are in the range of 1-3μm. In one aspect of the invention at least 90% of the crystals are in the range of the range of 1-5 μm. For example at least 90% of the crystals are in the range of 1-3 μm. In one aspect of the invention at least 92% of the crystals are in the range of 1-5 μm. For example at least 92% of the crystals are in the range of 1-3μm. In one aspect of the invention at least 95% of the crystals are in the range of 1-5 μm. For example at least 95% of the crystals are in the range of 1-3μm.

The crystals can comprise insulin such as human insulin, porcine insulin, bovine insulin or an insulin analogue. The crystals can also comprise a mixture of the mentioned insulins.

For example the crystals can comprise insulin selected from the group consisting of AspB28 human insulin, LysB28ProB29 human insulin, GlyA21ArgB31ArgB32 human insulin, LysB3GluB29 human insulin.

In one aspect of the invention a process for preparing crystals comprising insulin is provided. A process for preparing a crystal comprising insulin by providing an aqueous solution comprising: a) insulin b) zinc c) a phenolic agent d) a chaotropic agent and adjusting the pH of the solution to a pH in the range of 5,8-8,0 and allowing the insulin in the solution to crystallize, with the provision that the chaotropic agent is not urea. The insulin solution is prepared by dissolving insulin at basic pH. Zinc free insulin is dissolved in a 50 mM phosphate buffer with a pH between 8 and 10.

The concentration of the insulin solution used in the process according to the inventions may be in the range of 0.5 mg/ml to 250 mg/ml, 1 mg/ml to 200 mg/ml, 1.5 mg/ml to 150 mg/ml, 2 mg/ml to 100 mg/ml, or 2.5 mg/ml to 250 mg/ml.

To induce the crystallization process a precipitant is added to the solution. The precipitant can be in the form of a salt e.g. sodium chloride or an alcohol such as ethanol. The precipitant may be added to the solution at the same time as the other excipients a-d are added to the solution. Alternatively the precipitant is added to the solution after excipients a-d is added. The precipitant can be added to the solution before it is allowed to crystallize. Alternatively a part of the precipitant can be added to the solution before it is allowed to crystallize and a part of the precipitant can be added to the solution while it is allowed to precipitate.

When an alcohol is used for precipitating the crystals, it may be added to the solution in a concentration of 0-20% v/v based on the starting solution. An alcohol may be added to the solution in a concentration of 0-15% v/v, 0-13% v/v or 0-10% v/v. For example an alcohol in a concentration of 0-7% v/v or 0-5% v/v may be added to the solution.

When a salt is used as a precipitant, the salt can be added to the solution in a concentration of 0.2-2.5 mol/l, for example 0.5-1.5 mol/l, based on the starting solution.

In one aspect of the invention the phenolic agent can be selected from the group consisting of resorcinol, cresol, meta-cresol, phenol, methyl p-hydroxybenzoate and methyl 4-hydroxybenzoate. The phenolic agent can be added in a concentration of 1-100 mmol/l. When phenol is used it can be added in a concentration of 30-80 mmol/l for example about 60 mmol/l. When resorcinol is used it can be added in a concentration of about 10 mmol/l.

In one aspect of the invention the chaotropic additive belongs to the group of alkali metal salts of thiocyanate. For example the sodium or potassium salts of thiocyanate can be used. In one aspect a mixture of the sodium thiocyanate and potassium thiocyanate are used.

Depending on the pH of the solution these crystals belong to space group C2 or C222-_I, with unit cell parameters of a=101 A b=61 A c=63 A α=90° β=116° γ=90°, and of a=59 A b=220 A c=225 A α=β=γ=90°, respectively.

In one aspect of the invention the pH is adjusted so the pH of the solution is in the range of about 5.8-8.0, about 6.0-6.8, in the range of about 6.2 to 6.6, in the range of about 6.2-6.4 or the pH of the solution is approximately 6.3. This process will result in a crystal belonging to space group C222-_I with a unit cell constant of a=59 A b=220 A c=225 A α=β=γ=90°. In one aspect of the invention the pH is adjusted so the pH of the solution is in the range of about 5.8-8.0, about 6.2-7.8, in the range of about 6.5 to 7.5, in the range of about 6.8-7.2 or in the range of about 6.9-7.1 or the pH of the solution is approximately 7.0. This process will result in a crystal belonging to space group C2 with a unit cell constant of a=101 A b=61 A c=63 A α=90° β=1 16° γ=90°.

In one aspect of the invention the pH of the solution is adjusted with a buffer. The buffer can be a phosphate buffer such as a sodium phosphate buffer or a potassium buffer or a mixture thereof.

In one aspect of the invention the pH of the solution is adjusted with an acidic or an alkaline solution or a mixture thereof.

In one aspect of the invention there is provided an insulin crystal produced by the mentioned process.

In one aspect the invention is related to a pharmaceutical composition comprising a therapeutically effective amount of a crystal according to the invention. The composition can be formulated together with a pharmaceutically acceptable carrier and/or a pharmaceutically acceptable additive. The composition can be provided for the treatment of type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia in patients in need of such a treatment.

In one aspect of the invention, there is provided a pharmaceutical composition for treating type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia in a patient in need of such a treatment, the composition comprising a therapeutically effective amount of a crystal according to the invention in mixture with human insulin, an insulin analogue, an insulin derivative or a mixture thereof. The insulin analogue can have a rapid onset of action. The composition can be formulated with a pharmaceutically acceptable carriers and/or additives.

In one aspect the invention provides a pharmaceutical composition can be a mixture of a crystal according to the invention and a rapid acting insulin analogue selected group consisting of AspB28 human insulin; LysB28ProB29 human insulin and LysB3GluB29 human insulin. One aspect of the invention is related to a pharmaceutical composition comprising a therapeutically effective amount of a crystal according to the invention, which can be provided for pulmonary treatment of type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia in patients in need of such a treatment. The composition can be administered as a powder, a granule or a liquid and can be formulated with or without a pharmaceutically acceptable carrier and/ or pharmaceutically acceptable additives. In one aspect of the invention, there is provided a method of treating type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia in a patient in need of such a treatment, comprising administering to the patient a therapeutically effective amount of an pharmaceutical composition comprising a crystal according to the invention. In one aspect the composition can be formulated with or without a pharmaceutically acceptable carrier and/or pharmaceutical acceptable additives.

In one aspect of the invention, there is provided a method of treating type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia in a patient in need of such a treatment, comprising administering to the patient a therapeutically effective amount of an pharmaceutical composition comprising a crystal according to the invention in mixture with human insulin, an insulin analogue, an insulin derivative or a mixture thereof. The insulin analogue can have a rapid onset of action. The composition can be formulated with or without a pharmaceutically acceptable carriers and/or additives.

In one aspect of the invention, there is provided a method for pulmonary treatment of type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia comprising administering to the patient a therapeutically effective amount of an pharmaceutical composition comprising a crystal according to the invention, optionally in admixture with human insulin, an insulin analogue, an insulin derivative or a mixture thereof The insulin analogue can have a rapid onset of action. The composition can be formulated with or without a pharmaceutically acceptable carriers and/or additives.

In one aspect of the invention, there is provided a method for parenteral treatment of type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia comprising administering to the patient a therapeutically effective amount of an pharmaceutical composition comprising a crystal according to the invention, optionally in admixture with human insulin, an insulin analogue, an insulin derivative or a mixture thereof The insulin analogue can have a rapid onset of action. The composition can be formulated with or without a pharmaceutically acceptable carriers and/or additives.

In one aspect of the invention, there is provided a method for the manufacture of a pharmaceutical composition for the use in the treatment of type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia, the composition comprising a crystal according to the invention. The composition can be formulated with or without a pharmaceutically acceptable carrier and/or pharmaceutical acceptable additives.

In one aspect of the invention, there is provided a method for the manufacture of a pharmaceutical composition for the use in the treatment of type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia, the composition comprising a therapeutically effective amount of an a crystal according to the invention in mixture with human insulin, an insulin analogue, an insulin derivative or a mixture thereof. The insulin analogue can have a rapid onset of action. The composition can be formulated with or without a pharmaceutically acceptable carriers and/or additives. In one aspect of the invention, there is provided a method for the manufacture of a pharmaceutical composition for the use in the treatment of type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia, the composition being used pulmonary and comprising a crystal according to the invention optionally in mixture with human insulin, an insulin analogue, an insulin derivative or a mixture thereof The insulin analogue can have a rapid onset of action. The composition can be formulated with or without a pharmaceutically acceptable carriers and/or additives.

The crystal according to the invention and the rapid acting insulin analogue can be mixed in a ratio from about 90/10%; about 70/30% or about 50/50%.

PRODUCTION OF INSULIN

The insulin or a precursor thereof can be produced by either well-know peptide synthesis or by well known recombinant production in suitable transformed microorganisms. Thus the insulin can be produced by a method which comprises culturing a host cell containing a DNA sequence encoding the polypeptide and capable of expressing the polypeptide in a suitable nu- trient medium under conditions permitting the expression of the peptide, after which the resulting peptide is recovered from the culture.

The medium used to culture the cells may be any conventional medium suitable for growing the host cells, such as minimal or complex media containing appropriate supplements. Suitable media are available from commercial suppliers or may be prepared according to pub- lished recipes (e.g. in catalogues of the American Type Culture Collection). The peptide produced by the cells may then be recovered from the culture medium by conventional procedures including separating the host cells from the medium by centrifugation or filtration, precipitating the proteinaceous components of the supernatant or filtrate by means of a salt, e.g. ammonium sulphate, purification by a variety of chromatographic procedures, e.g. ion exchange chromatog- raphy, gel filtration chromatography, affinity chromatography, or the like, dependent on the type of peptide in question.

The DNA sequence encoding the insulin may suitably be of genomic or cDNA origin, for instance obtained by preparing a genomic or cDNA library and screening for DNA sequences coding for all or part of the polypeptide by hybridisation using synthetic oligonucleotide probes in accordance with standard techniques (see, for example, Sambrook, J, Fritsch, EF and Maniatis, T, Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory Press, New York, 1989). The DNA sequence encoding the parent insulin may also be prepared synthetically by established standard methods, e.g. the phosphoamidite method described by Beaucage and Caruthers, Tetrahedron Letters 22 (1981 ), 1859 - 1869, or the method described by Matthes et ai, EMBO Journal 3 (1984), 801 - 805. The DNA sequence may also be prepared by polymerase chain reaction using specific primers, for instance as described in US 4,683,202 or Saiki et ai, Science 239 (1988), 487 - 491.

The DNA sequence may be inserted into any vector which may conveniently be sub- jected to recombinant DNA procedures, and the choice of vector will often depend on the host cell into which it is to be introduced. Thus, the vector may be an autonomously replicating vector, i.e. a vector which exists as an extrachromosomal entity, the replication of which is independent of chromosomal replication, e.g. a plasmid. Alternatively, the vector may be one which, when introduced into a host cell, is integrated into the host cell genome and replicated together with the chromosome(s) into which it has been integrated.

The vector is for example an expression vector in which the DNA sequence encoding the insulin is operably linked to additional segments required for transcription of the DNA, such as a promoter. The promoter may be any DNA sequence which shows transcriptional activity in the host cell of choice and may be derived from genes encoding proteins either homologous or heterologous to the host cell. Examples of suitable promoters for directing the transcription of the DNA encoding the insulin in a variety of host cells are well known in the art, cf. for instance Sambrook et ai, supra.

The DNA sequence encoding the insulin may also, if necessary, be operably connected to a suitable terminator, polyadenylation signals, transcriptional enhancer sequences, and translational enhancer sequences. The recombinant vector of the invention may further comprise a DNA sequence enabling the vector to replicate in the host cell in question.

The vector may also comprise a selectable marker, e.g. a gene the product of which complements a defect in the host cell or one which confers resistance to a drug, e.g. ampicillin, kanamycin, tetracyclin, chloramphenicol, neomycin, hygromycin or methotrexate. To direct a peptide of the present invention into the secretory pathway of the host cells, a secretory signal sequence (also known as a leader sequence, prepro sequence or pre sequence) may be provided in the recombinant vector. The secretory signal sequence is joined to the DNA sequence encoding the peptide in the correct reading frame. Secretory signal sequences are commonly positioned 5' to the DNA sequence encoding the peptide. The secretory signal sequence may be that normally associated with the peptide or may be from a gene encoding another secreted protein.

The procedures used to ligate the DNA sequences coding for the insulin, the promoter and optionally the terminator and/or secretory signal sequence, respectively, and to insert them into suitable vectors containing the information necessary for replication, are well known to persons skilled in the art (cf., for instance, Sambrook et al.., supra).

The host cell into which the DNA sequence or the recombinant vector is introduced may be any cell which is capable of producing the present peptide and includes bacteria, yeast, fungi and higher eukaryotic cells. Examples of suitable host cells well known and used in the art are, without limitation, E. coli, Saccharomyces cerevisiae, or mammalian BHK or CHO cell lines.

The insulin molecule can then be converted into insulin derivatives by introducing of the relevant substituent in either the B1 position or in the chosen Lys position in the B-chain. The substituent can be introduced by any convenient method and many methods are disclosed in the prior art for acylation of an amino group.

PHARMACEUTICAL COMPOSITIONS

The crystal comprising insulin of this invention can, for example, be administered subcutaneously, orally, nasally or pulmonary.

For subcutaneous administration, the crystals comprising insulin are formulated analogously with the formulation of known insulin. Furthermore, for subcutaneous administration, the crystals comprising insulin of this invention are administered analogously with the administration of known insulins and, generally, the physicians are familiar with this procedure.

The crystal comprising insulin of this invention may be administered by inhalation in a dose effective manner to increase circulating insulin levels and/or to lower circulating glucose levels. Such administration can be effective for treating disorders such as diabetes or hyperglycaemia. Achieving effective doses of insulin requires administration of an inhaled dose of crystals comprising insulin of this invention of more than about 0.5 μg/kg to about 50 μg/kg. A therapeutically effective amount can be determined by a knowledgeable practitioner, who will take into account factors including insulin level, blood glucose levels, the physical condition of the patient, the patient's pulmonary status, or the like.

According to the invention, crystals comprising insulin of this invention may be delivered by inhalation to achieve rapid absorption thereof. Administration by inhalation can result in pharmacokinetics comparable to subcutaneous administration of insulin. Inhalation of a crystal comprising insulin of this invention leads to a rapid rise in the level of circulating insulin followed by a rapid fall in blood glucose levels. Different inhalation devices typically provide similar pharmacokinetics when similar particle sizes and similar levels of lung deposition are compared. According to the invention, crystals comprising insulin of this invention may be delivered by any of a variety of inhalation devices known in the art for administration of a therapeutic agent by inhalation. These devices include metered dose inhalers, nebulizers, dry powder generators, sprayers, and the like. Crystals comprising insulin of this invention is delivered by a dry powder inhaler or a sprayer. There are a several desirable features of an in- halation device for administering crystals of this invention. For example, delivery by the inhalation device is advantageously reliable, reproducible, and accurate. The inhalation device should deliver small particles, for example, less than about 10 μm, for example about 1-5 μm, for good respirability. Some specific examples of commercially available inhalation devices suitable for the practice of this invention are Turbohaler™ (Astra), Rotahaler^® (Glaxo), Diskus^® (Glaxo), Spiros™ inhaler (Dura), devices marketed by Inhale Therapeutics, AERx™ (Aradigm), the Ultravent^® nebulizer (Mallinckrodt), the Acorn II^® nebulizer (Marquest Medical Products), the Ventolin^® metered dose inhaler (Glaxo), the Spinhaler^® powder inhaler (Fisons), or the like.

As those skilled in the art will recognize, the formulation of insulin crystals compris- ing insulin of the invention, the quantity of the formulation delivered, and the duration of administration of a single dose depend on the type of inhalation device employed. For some aerosol delivery systems, such as nebulizers, the frequency of administration and length of time for which the system is activated will depend mainly on the concentration of insulin conjugate in the aerosol. For example, shorter periods of administration can be used at higher concentrations of insulin conjugate in the nebulizer solution. Devices such as metered dose inhalers can produce higher aerosol concentrations, and can be operated for shorter periods to deliver the desired amount of insulin conjugate. Devices such as powder inhalers deliver active agent until a given charge of agent is expelled from the device. In this type of inhaler, the amount of crystals comprising insulin of this invention in a given quantity of the powder determines the dose delivered in a single administration.

The particle size of crystals comprising insulin of this invention in the formulation delivered by the inhalation device is critical with respect to the ability of insulin to make it into the lungs, and into the lower airways or alveoli. The crystals comprising insulin of this invention can be formulated so that at least about 10% of the insulin conjugate delivered is depos- ited in the lung, for example about 10 to about 20%, or more. It is known that the maximum efficiency of pulmonary deposition for mouth breathing humans is obtained with particle sizes of about 2 μm to about 3 μm. Pulmonary deposition decreases substantially when particle sizes are above about 5 μm. Particle sizes below about 1 μm cause pulmonary deposition to decrease, and it becomes difficult to deliver particles with sufficient mass to be therapeuti- cally effective. Thus, particles of the crystals delivered by inhalation have a particle size less than about 10 μm, for example in the range of about 1 μm to about 5 μm. The formulation of the crystals is selected to yield the desired particle size in the chosen inhalation device.

Advantageously for administration as a dry powder, crystals comprising insulin of this invention is prepared in a particulate form with a particle size of less than about 10 μm, for example about 1 to about 5 μm. The particle size is effective for delivery to the alveoli of the patient's lung. The dry powder is largely composed of particles produced so that a majority of the particles have a size in the desired range. Advantageously, at least about 50% of the dry powder is made of particles having a diameter less than about 10 μm. Such formulations can be achieved by spray drying, milling, or critical point condensation of a solution containing insulin conjugate and other desired ingredients. Other methods also suitable for generating particles useful in the current invention are known in the art.

The particles are usually separated from a dry powder formulation in a container and then transported into the lung of a patient via a carrier air stream. Typically, in current dry powder inhalers, the force for breaking up the solid is provided solely by the patient's inhala- tion. In another type of inhaler, air flow generated by the patient's inhalation activates an impeller motor which deagglomerates the particles.

Formulations of crystals comprising insulin of this invention for administration from a dry powder inhaler typically include a finely divided dry powder containing the derivative, but the powder can also include a bulking agent, carrier, excipient, another additive, or the like. Additives can be included in a dry powder formulation of insulin conjugate, for example, to dilute the powder as required for delivery from the particular powder inhaler, to facilitate processing of the formulation, to provide advantageous powder properties to the formulation, to facilitate dispersion of the powder from the inhalation device, to stabilize the formulation (for example, antioxidants or buffers), to provide taste to the formulation, or the like. Advan- tageously, the additive does not adversely affect the patient's airways. The crystals comprising insulin can be mixed with an additive at a molecular level or the solid formulation can include particles of the insulin conjugate mixed with or coated on particles of the additive. Typical additives include mono-, di-, and polysaccharides; sugar alcohols and other polyols, such as, for example, lactose, glucose, raffinose, melezitose, lactitol, maltitol, trehalose, sucrose, mannitol, starch, or combinations thereof; surfactants, such as sorbitols, diphosphatidyl cho- line, or lecithin; or the like. Typically an additive, such as a bulking agent, is present in an amount effective for a purpose described above, often at about 50% to about 90% by weight of the formulation. Additional agents known in the art for formulation of a protein such as insulin analogue protein can also be included in the formulation. A spray including the crystal comprising insulin of this invention can be produced by forcing a suspension or solution of insulin conjugate through a nozzle under pressure. The nozzle size and configuration, the applied pressure, and the liquid feed rate can be chosen to achieve the desired output and particle size. An electrospray can be produced, for example, by an electric field in connection with a capillary or nozzle feed. Advantageously, particles of insulin conjugate delivered by a sprayer have a particle size less than about 10 μm, for example in the range of about 1 μm to about 5 μm.

Formulations of crystals comprising insulin of this invention suitable for use with a sprayer will typically include the crystals in an aqueous solution at a concentration of about 1 mg to about 20 mg of insulin conjugate per ml of solution. The formulation can include agents such as an excipient, a buffer, an isotonicity agent, a preservative, a surfactant, and, for example zinc. The formulation can also include an excipient or agent for stabilization of the crystals , such as a buffer, a reducing agent, a bulk protein, or a carbohydrate. Bulk proteins useful in formulating insulin conjugates include albumin, protamine, or the like. Typical carbohydrates useful in formulating insulin conjugates include sucrose, mannitol, lactose, treha- lose, glucose, or the like. The crystal formulation can also include a surfactant, which can reduce or prevent surface-induced aggregation of the insulin conjugate caused by atomiza- tion of the solution in forming an aerosol. Various conventional surfactants can be employed, such as polyoxyethylene fatty acid esters and alcohols, and polyoxyethylene sorbitol fatty acid esters. Amounts will generally range between about 0.001 and about 4% by weight of the formulation.

Pharmaceutial compositions containing a crystal comprising insulin according to the present invention may also be administered nasally. The pharmaceutical composition may be administered as a liquid composition, a dry composition or a gel. For drug delivery via the nose the crystals may be above 10 μm in order to secure deposition in the nasal cavity and to avoid that the particles are carried further down to the tracheobronchial and pulmonary region. There is no clear understanding of a upper size limit, but there probably is an upper particle size above which particles for a number of reasons will not demonstrate efficacy and maybe even could lead to local irritation. Pharmaceutical compositions containing a crystal comprising insulin according to the present invention may also be administered parenterally to patients in need of such a treatment. Parenteral administration may be performed by subcutaneous, intramuscular or intravenous injection by means of a syringe, optionally a pen-like syringe. Alternatively, parenteral administration can be performed by means of an infusion pump.

Injectable compositions of the crystals of the invention can be prepared using the conventional techniques of the pharmaceutical industry which involve dissolving and mixing the ingredients as appropriate to give the desired end product. Thus, according to one procedure, a crystal comprising insulin according to the invention is dissolved in an amount of water which is somewhat less than the final volume of the composition to be prepared. An isotonic agent, a preservative and a buffer is added as required and the pH value of the solution is adjusted - if necessary - using an acid, e.g. hydrochloric acid, or a base, e.g. aqueous sodium hydroxide as needed. Finally, the volume of the solution is adjusted with water to give the desired concentration of the ingredients. In a further aspect of the invention the buffer is selected from the group consisting of sodium acetate, sodium carbonate, citrate, glycylglycine, histidine, glycine, lysine, arginine, sodium dihydrogen phosphate, disodium hydrogen phosphate, sodium phosphate, and tris(hydroxymethyl)-aminomethan, bicine, tricine, malic acid, succinate, maleic acid, fumaric acid, tartaric acid, aspartic acid or mixtures thereof. Each one of these specific buffers constitutes an alternative aspect of the invention.

In a further aspect of the invention the formulation further comprises a pharmaceutically acceptable preservative which may be selected from the group consisting of phenol, o-cresol, m-cresol, p-cresol, methyl p-hydroxybenzoate, propyl p- hydroxybenzoate, 2-phenoxyethanol, butyl p-hydroxybenzoate, 2-phenylethanol, benzyl alcohol, chlorobutanol, and thiomerosal, bronopol, benzoic acid, imidurea, chlorohexidine, sodium dehydroacetate, chlorocresol, ethyl p-hydroxybenzoate, benzethonium chloride, chlorphenesine (3p-chlorphenoxypropane-1 ,2-diol) or mixtures thereof. In a further aspect of the invention the preservative is present in a concentration from 0.1 mg/ml to 20 mg/ml. In a further aspect of the invention the preservative is present in a concentration from 0.1 mg/ml to 5 mg/ml. In a further aspect of the invention the preservative is present in a concentration from 5 mg/ml to 10 mg/ml. In a further aspect of the invention the preservative is present in a concentration from 10 mg/ml to 20 mg/ml. Each one of these specific preservatives constitutes an alternative aspect of the invention. The use of a preservative in pharmaceutical compositions is well-known to the skilled person. For convenience reference is made to Remington: The Science and Practice of Pharmacy, 19^th edition, 1995. In a further aspect of the invention the formulation further comprises an isotonic agent which may be selected from the group consisting of a salt (e.g. sodium chloride), a sugar or sugar alcohol, an amino acid (e.g. glycine, L-histidine, arginine, lysine, isoleucine, aspartic acid, tryptophan, threonine), an alditol (e.g. glycerol (glycerine), 1 ,2-propanediol (propyleneglycol), 1 ,3-propanediol, 1 ,3-butanediol) polyethyleneglycol (e.g. PEG400), or mixtures thereof. Any sugar such as mono-, di-, or polysaccharides, or water-soluble glucans, including for example fructose, glucose, mannose, sorbose, xylose, maltose, lactose, sucrose, trehalose, dextran, pullulan, dextrin, cyclodextrin, soluble starch, hydroxyethyl starch and carboxymethylcellulose-Na may be used. In one aspect the sugar additive is sucrose. Sugar alcohol is defined as a C4-C8 hydrocarbon having at least one — OH group and includes, for example, mannitol, sorbitol, inositol, galactitol, dulcitol, xylitol, and arabitol. In one aspect the sugar alcohol additive is mannitol. The sugars or sugar alcohols mentioned above may be used individually or in combination. There is no fixed limit to the amount used, as long as the sugar or sugar alcohol is soluble in the liquid preparation and does not adversely effect the stabilizing effects achieved using the methods of the invention. In one aspect, the sugar or sugar alcohol concentration is between about 1 mg/ml and about 150 mg/ml. In a further aspect of the invention the isotonic agent is present in a concentration from 1 mg/ml to 50 mg/ml. In a further aspect of the invention the isotonic agent is present in a concentration from 1 mg/ml to 7 mg/ml. In a further aspect of the invention the isotonic agent is present in a concentration from 8 mg/ml to 24 mg/ml. In a further aspect of the invention the isotonic agent is present in a concentration from 25 mg/ml to 50 mg/ml. Each one of these specific isotonic agents constitutes an alternative aspect of the invention. The use of an isotonic agent in pharmaceutical compositions is well-known to the skilled person. For convenience reference is made to Remington: The Science and Practice of Pharmacy, 19^th edition, 1995.

Typical isotonic agents are sodium chloride, mannitol, dimethyl sulfone and glycerol and typical preservatives are phenol, m-cresol, methyl p-hydroxybenzoate and benzyl alcohol.

Examples of suitable buffers are sodium acetate, glycylglycine, HEPES (4-(2- hydroxyethyl)-1-piperazineethanesulfonic acid) and sodium phosphate. Compositions containing crystals comprising insulin of this invention can be used in the treatment of states which are sensitive to insulin. Thus, they can be used in the treatment of type 1 diabetes, type 2 diabetes and hyperglycaemia for example as sometimes seen in seriously injured persons and persons who have undergone major surgery. The optimal dose level for any patient will depend on a variety of factors including the efficacy of the specific insulin employed, the age, body weight, physical activity, and diet of the patient, on a possible combination with other drugs, and on the severity of the state to be treated. It is recommended that the daily dosage of the crystals comprising insulin of this invention be determined for each individual patient by those skilled in the art in a similar way as for known insulin compositions.

Where expedient, the crystals s of this invention may be used in mixture with other types of insulin, e.g. insulin analogues with a more rapid onset of action. Examples of such insulin analogues are described e.g. in the European patent applications having the publication Nos. EP 214826 (Novo Nordisk A/S), EP 375437 (Novo Nordisk A/S) and EP 383472 (EIi Lilly & Co.).

The invention will be summarized in the following paragraphs 1. A crystal comprising insulin wherein the crystal is being grown in the presence of a chaotropic agent provided that the crystal is not grown in the presence of urea.

2. Crystal according to paragraph 1 , wherein the crystal belongs to space group C222-, with a unit cell constants of a=59 A b=220 A c=225 A α=β=γ=90°or space group C2 with a unit cell constant of a=101 A b=61 A c=63 A α=90° β=116° γ=90° when determined by X-ray diffraction.

3. Crystal according to paragraph 1-2, wherein the crystal comprises zinc.

4. Crystal according to paragraphs 1-3, wherein the crystal also comprises a phenolic agent.

5. Crystal according to paragraphs 1-4, wherein the phenolic agent is selected from the group consisting of resorcinol, cresol, meta-cresol, phenol, methyl p-hydroxybenzoate and methyl 4-hydroxybenzoate.

6. Crystal according to paragraphs 1-5, wherein the chaotropic agent belongs to the group of alkali metal salts of thiocyanate or arginine.

7. Crystal according to paragraphs 1 or 6, wherein the alkali metal salts of thiocy- anate can be sodium thiocyanate or potassium thiocyanate.

8. Crystal according to any of the preceding paragraphs, wherein at least 50% of the crystals are in the range of the range of 1-30 μm.

9. Crystal according to any of the preceding paragraphs, wherein at least 70% of the crystals are in the range of the range of 1-30 μm. 10. Crystal according to any of the preceding paragraphs, wherein at least 90% of the crystals are in the range of the range of 1-30 μm.

1 1. Crystal according to any of the preceding paragraphs, wherein at least 50% of the crystals are in the range of the range of 1-20 μm.

12 Crystal according to any of the preceding paragraphs, wherein at least 70% of the crystals are in the range of the range of 1-20 μm. 13. Crystal according to any of the preceding paragraphs, wherein at least 90% of the crystals are in the range of the range of 1-20 μm.

14. Crystal according to any of the preceding paragraphs, wherein at least 50% of the crystals are in the range of the range of 1-10 μm. 15. Crystal according to any of the preceding paragraphs, wherein at least 70% of the crystals are in the range of the range of 1-10 μm.

16. Crystal according to any of the preceding paragraphs, wherein at least 90% of the crystals are in the range of the range of 1-10 μm.

17. Crystal according to any of the preceding paragraphs, wherein at least 50% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

18. Crystal according to any of the preceding paragraphs, wherein at least 70% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

19. Crystal according to any of the preceding paragraphs, wherein at least 90% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm. 20. Crystal according to any of the preceding paragraphs, wherein at least 92% of the crystals are in the range of 1-5 μm, for example 1-3 μm.

21. Crystal according to any of the preceding paragraphs, wherein at least 95% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

22. Crystal according to any of paragraphs 1-10, wherein at least 50% of the crys- tals are in the range of the range of 15-30 μm.

23. Crystal according to any of paragraphs 1-10 and 22, wherein at least 70% of the crystals are in the range of the range of 15-30 μm.

24. Crystal according to any of paragraphs 1-10 and 22-23, wherein at least 90% of the crystals are in the range of the range of 15-30 μm. 25. Crystal according to any of paragraphs 1-10 and 22-24, wherein at least 50% of the crystals are in the range of the range of 20-30 μm.

26. Crystal according to any of paragraphs 1-10 and 22-25, wherein at least 70% of the crystals are in the range of the range of 20-30 μm.

27. Crystal according to any of paragraphs 1-10 and 22-26, wherein at least 90% of the crystals are in the range of the range of 20-30 μm.

28. Crystal according to any of paragraphs 1-10 and 22-27 ^', wherein at least 50% of the crystals are in the range of the range of 20-25 μm.

29. Crystal according to any of paragraphs 1-10 and 22-28, wherein at least 70% of the crystals are in the range of the range of 20-25 μm. 30. Crystal according to any of paragraphs 1-10 and 22-29, wherein at least 90% of the crystals are in the range of the range of 20-25 μm.

31. Crystal according to any of paragraphs 1-10 and 22-30, wherein at least 95% of the crystals are in the range of the range of 20-25 μm. 32. Crystal according to any of paragraphs 1-31 , wherein the insulin is human insulin, porcine insulin or an insulin analogue.

33. Crystal according to paragraph 1-32, wherein the insulin is an insulin analogue selected from the group consisting of AspB28 human insulin, LysB28ProB29 human insulin, GlyA21ArgB31ArgB32 human insulin, LysB3GluB29 human insulin. 34. Crystal according to paragraphs 1-33, wherein the crystal is provided at a pH between about 5.8 and about 8.0.

35. Crystal according to paragraphs 1-34, wherein the crystal is provided a pH between about 6.0 and about 6.8.

36. Crystal according to paragraphs 1-35, wherein the crystal is provided a pH be- tween about 6.2 and about 6.6.

37. Crystal according to paragraphs 1-36, wherein the crystal is provided a pH between about 6.2 and about 6.4.

38. Crystal according to paragraphs 1-37, wherein the crystal is provided a pH about 6.3. 39. Crystal according to paragraphs 1-34, wherein the crystal is provided a pH between about 6.2 and about 7.8.

40. Crystal according to paragraphs 1-34 and paragraph 39, wherein the crystal is provided a pH between about 6.5 and about 7.5.

41. Crystal according to paragraphs 1-34 and paragraphs 39-40, wherein the crystal is provided a pH between about 6.8 and about 7.2.

42. Crystal according to paragraphs 1-34 and paragraphs 39-41 , wherein the crystal is provided a pH between about 6.9 and about 7.1.

43. Crystal according to paragraphs 1-34 and paragraphs 39-42, wherein the crystal is provided a pH about 7.0. 44. A process for preparing a crystal comprising insulin by providing an aqueous solution comprising: a) insulin b) zinc c) a phenolic agent d) a chaotropic agent and adjusting the pH of the solution to a pH in the range of 5,8-8,0 and allowing the insulin in the solution to crystallize, with the provision that the chaotropic agent is not urea. 45. A process according to paragraph 44, wherein the solution of insulin is present in a concentration of 0.5 mg/ml to 250 mg/ml. 46. A process according to paragraphs 44-45, wherein the solution of insulin is present in a concentration of 2 mg/ml to 100 mg/ml.

47. Process according to paragraphs 44-46, wherein a precipitant is added to the solution before it is allowed to crystallize.

48. Process according to paragraphs AA-Al, wherein a precipitant is added to the solution before and while it is allowed to crystallize.

49. Process according to paragraphs 44-48, wherein the precipitant is an alcohol.

50. Process according to paragraphs 44-49, wherein the precipitant is ethanol.

51. Process according to paragraphs 44-50, wherein the alcohol is added in a concentration of 0-20% v/v, 0-15% v/v, 0-13% v/v, 0-10% v/v, 0-7% v/v or 0-5% v/v. 52. Process according to paragraphs 44-48, wherein the precipitant is a salt.

53. Process according to paragraphs 44-48 and 52, wherein the precipitant is sodium chloride.

54. Process according to paragraphs 44-48 and 52-53, wherein the salt is added in a concentration of 0.2-2.5 mol/l for example 0.5-1.5 mol/l. 55. Process according to paragraphs 44-54, wherein the phenolic agent is selected from the group consisting of resorcinol, cresol, meta-cresol, phenol, methyl p- hydroxybenzoate and methyl 4-hydroxybenzoate.

56. Process according to paragraphs 44-55, wherein the concentration of the phenolic agent is 1-100 mmol/l. 57. Process according to paragraphs 44-56, wherein the phenolic agent is phenol in a concentration of 30-80 mmol/l for example about 60 mmol/l.

58. Process according to paragraphs 44-57, wherein the phenolic agent is resorcinol in a concentration of about 10 mmol/l.

59. Process according to paragraphs 44-58, wherein the chaotropic agent is argin- ine or belongs to the group of alkali metal salts of thiocyanate.

60. Process according to paragraph 59, wherein the alkali metal salts of thiocyanate is sodium thiocyanate or potassium thiocyanate.

61. Process according to any of paragraphs 44-60, wherein the pH is adjusted so the pH of the solution is in the range of about 5.8 to about 8.0. 62. Process according to any of paragraphs 44-61 , wherein the pH is adjusted so the pH of the solution is in the range of about 6.0 to about 6.8.

63. Process according to any of paragraphs 44-62, wherein the pH is adjusted so the pH of the solution is in the range of about 6.2 to about 6.6. 64. Process according to any of paragraphs 44-63, wherein the pH is adjusted so the pH of the solution is in the range of about 6.2 to about 6.4.

65. Process according to any of paragraphs 44-64, wherein the pH is adjusted so the pH of the solution is approximately 6.3.

66. Process according to any of paragraphs 44-61 , wherein the pH is adjusted so the pH of the solution is in the range of about 6.2 to about 7.8.

67. Process according to any of paragraphs 44-61 or paragraph 66, wherein the pH is adjusted so the pH of the solution is in the range of about 6.5 to about7.5.

68. Process according to any of paragraphs 44-61 or paragraphs 66-67, wherein the pH is adjusted so the pH of the solution is in the range of about 6.8 to about 7.2. 69. Process according to any of paragraphs 44-61 or paragraphs 66-68, wherein the pH is adjusted so the pH of the solution is in the range of about 6.9 to about 7.1.

70. Process according to any of paragraphs 44-61 or paragraphs 66-69, wherein the pH is adjusted so the pH of the solution is approximately 7.0

71. Process according to any of paragraphs 44-70, wherein the buffer is a phos- phate buffer.

72. Process according to paragraphs 44-71 , wherein the pH is adjusted with a buffer which is a sodium phosphate buffer or a potassium buffer or a mixture thereof.

73. Process according to paragraphs 44-70, wherein the pH is adjusted with an acidic or a alkaline solution or a mixture thereof. 74. Insulin crystal produced by the process of paragraphs 44-73.

75. A crystal comprising insulin wherein the structure of the crystal is orthorhombic.

76. Crystal according to paragraph 75, wherein the wherein the crystal belongs to space group C222-, with a unit cell constants of a=59 A b=220 A c=225 A α=β=γ=90° when measured by X-ray diffraction. 77. Crystal according to paragraphs 75-76, wherein the crystal is provided a pH between about 6.0 and about 6.8.

78. Crystal according to paragraphs 75-77, wherein the crystal is provided a pH between about 6.2 and about 6.6.

79. Crystal according to paragraphs 75-78, wherein the crystal is provided a pH be- tween about 6.2 and about 6.4. 80. Crystal according to paragraphs 75-79, wherein the crystal is provided a pH about 6.3.

81. Crystal according to paragraphs 75-80, wherein the crystal comprises zinc.

82. Crystal according to paragraphs 75-81 , wherein the crystal also comprises a phenolic agent.

83. Crystal according to paragraphs 75-82, wherein the phenolic agent is selected from the group consisting of resorcinol, cresol, meta-cresol, phenol, methyl p- hydroxybenzoate and methyl 4-hydroxybenzoate.

84. Crystal according to paragraphs 75-83, wherein the chaotropic agent belongs to the group of alkali metal salts of thiocyanate or arginine.

85. Crystal according to paragraphs 75-84, wherein the alkali metal salts of thiocyanate can be sodium thiocyanate or potassium thiocyanate.

86. Crystal according to paragraphs 75-85, wherein at least 50% of the crystals are in the range of the range of 1-30 μm. 87. Crystal according to paragraphs 75-86, wherein at least 70% of the crystals are in the range of the range of 1-30 μm.

88. Crystal according to paragraphs 75-87, wherein at least 90% of the crystals are in the range of the range of 1-30 μm.

89. Crystal according to paragraphs 75-88, wherein at least 50% of the crystals are in the range of the range of 1 -20 μm.

90. Crystal according to paragraphs 75-89, wherein at least 70% of the crystals are in the range of the range of 1-20 μm.

91. Crystal according to paragraphs 75-90, wherein at least 90% of the crystals are in the range of the range of 1-20 μm. 92. Crystal according to paragraphs 75-91 , wherein at least 50% of the crystals are in the range of the range of 1-10 μm.

93. Crystal according to paragraphs 75-92, wherein at least 70% of the crystals are in the range of the range of 1-10 μm.

94. Crystal according to paragraphs 75-93, wherein at least 90% of the crystals are in the range of the range of 1 -10 μm.

95. Crystal according to paragraphs 75-94, wherein at least 50% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

96. Crystal according to paragraphs 75-95, wherein at least 70% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm. 97. Crystal according to paragraphs 75-96, wherein at least 90% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

98. Crystal according to paragraphs 75-97, wherein at least 92% of the crystals are in the range of 1-5 μm, for example 1-3 μm. 99. Crystal according to paragraphs 75-98, wherein at least 95% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

100. Crystal according to paragraphs 75-88, wherein at least 50% of the crystals are in the range of the range of 15-30 μm.

101. Crystal according to paragraphs 75-88 and 100, wherein at least 70% of the crystals are in the range of the range of 15-30 μm.

102. Crystal according to paragraphs 75-88 and 100-101 , wherein at least 90% of the crystals are in the range of the range of 15-30 μm.

103. Crystal according to paragraphs 75-88 and 100-102, wherein at least 50% of the crystals are in the range of the range of 20-30 μm. 104. Crystal according to paragraphs 75-88 and 100-103, wherein at least 70% of the crystals are in the range of the range of 20-30 μm.

105. Crystal according to paragraphs 75-88 and 100-104, wherein at least 90% of the crystals are in the range of the range of 20-30 μm.

106. Crystal according to paragraphs 75-88 and 100-105, wherein at least 50% of the crystals are in the range of the range of 20-25 μm.

107. Crystal according to paragraphs 75-88 and 100-106, wherein at least 70% of the crystals are in the range of the range of 20-25 μm.

108. Crystal according to paragraphs 75-88 and 100-107, wherein at least 90% of the crystals are in the range of the range of 20-25 μm. 109. Crystal according to paragraphs 75-108, wherein the insulin is human insulin, porcine insulin or an insulin analogue.

1 10. Crystal according to paragraphs 75-109, wherein the insulin is an insulin analogue selected from the group consisting of AspB28 human insulin, LysB28ProB29 human insulin, GlyA21ArgB31ArgB32 human insulin, LysB3GluB29 human insulin. 1 11. A crystal comprising insulin wherein the structure of the crystal is monoclinic.

1 12. Crystal according to paragraph 11 1 , wherein the wherein the crystal belongs to space group C2 with a unit cell constant of a=101 A b=61 A c=63 A α=90° β=1 16° γ=90° when measured by X-ray diffraction.

1 13. Crystal according to paragraphs 11 1-112, wherein the crystal is provided a pH between about 6.2 and about 7.8. 1 14. Crystal according to paragraphs 11 1-113, wherein the crystal is provided a pH between about 6.5 and about 7.5.

1 15. Crystal according to paragraphs 11 1-114, wherein the crystal is provided a pH between about 6.8 and about 7.2. 1 16. Crystal according to paragraphs 11 1-115, wherein the crystal is provided a pH between about 6.9 and about 7.1.

1 17. Crystal according to paragraphs 11 1-116, wherein the crystal is provided a pH about 7.0.

1 18. Crystal according to paragraphs 11 1-117, wherein the crystal comprises zinc. 1 19. Crystal according to paragraphs 11 1-118, wherein the crystal also comprises a phenolic agent.

120. Crystal according to paragraphs 11 1-119, wherein the phenolic agent is selected from the group consisting of resorcinol, cresol, meta-cresol, phenol, methyl p- hydroxybenzoate and methyl 4-hydroxybenzoate. 121. Crystal according to paragraphs 11 1-120, wherein the chaotropic agent belongs to the group of alkali metal salts of thiocyanate or arginine.

122. Crystal according to paragraphs 11 1-121 , wherein the alkali metal salts of thiocyanate can be sodium thiocyanate or potassium thiocyanate.

123. Crystal according to paragraphs 11 1-122, wherein at least 50% of the crystals are in the range of the range of 1-30 μm.

124. Crystal according to paragraphs 11 1-123, wherein at least 70% of the crystals are in the range of the range of 1-30 μm.

125. Crystal according to paragraphs 11 1-124, wherein at least 90% of the crystals are in the range of the range of 1-30 μm. 126. Crystal according to paragraphs 11 1-125, wherein at least 50% of the crystals are in the range of the range of 1-20 μm.

127. Crystal according to paragraphs 11 1-126, wherein at least 70% of the crystals are in the range of the range of 1-20 μm.

128. Crystal according to paragraphs 11 1-127, wherein at least 90% of the crystals are in the range of the range of 1-20 μm.

129. Crystal according to paragraphs 11 1-128, wherein at least 50% of the crystals are in the range of the range of 1-10 μm.

130. Crystal according to paragraphs 11 1-129, wherein at least 70% of the crystals are in the range of the range of 1-10 μm. 131. Crystal according to paragraphs 11 1-130, wherein at least 90% of the crystals are in the range of the range of 1-10 μm.

132. Crystal according to paragraphs 11 1-131 , wherein at least 50% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm. 133. Crystal according to paragraphs 11 1-132, wherein at least 70% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

134. Crystal according to paragraphs 11 1-133, wherein at least 90% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

135. Crystal according to paragraphs 11 1-134, wherein at least 92% of the crystals are in the range of 1-5 μm, for example 1-3 μm.

136. Crystal according to paragraphs 11 1-135, wherein at least 95% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

137. Crystal according to paragraphs 11 1-125, wherein at least 50% of the crystals are in the range of the range of 15-30 μm. 138. Crystal according to paragraphs 11 1-125 and 137, wherein at least 70% of the crystals are in the range of the range of 15-30 μm.

139. Crystal according to paragraphs 11 1-125 and 137-138, wherein at least 90% of the crystals are in the range of the range of 15-30 μm.

140. Crystal according to paragraphs 11 1-125 and 137-139, wherein at least 50% of the crystals are in the range of the range of 20-30 μm.

141. Crystal according to paragraphs 11 1-125 and 137-140, wherein at least 70% of the crystals are in the range of the range of 20-30 μm.

142. Crystal according to paragraphs 11 1-125 and 137-141 , wherein at least 90% of the crystals are in the range of the range of 20-30 μm. 143. Crystal according to paragraphs 11 1-125 and 137-142, wherein at least 50% of the crystals are in the range of the range of 20-25 μm.

144. Crystal according to paragraphs 11 1-125 and 137-143, wherein at least 70% of the crystals are in the range of the range of 20-25 μm.

145. Crystal according to paragraphs 11 1-125 and 137-144, wherein at least 90% of the crystals are in the range of the range of 20-25 μm.

146. Crystal according to paragraphs 11 1-145, wherein the insulin is human insulin, porcine insulin or an insulin analogue.

147. Crystal according to paragraphs 11 1-146, wherein the insulin is an insulin analogue selected from the group consisting of AspB28 human insulin, LysB28ProB29 human insulin, GlyA21ArgB31ArgB32 human insulin, LysB3GluB29 human insulin. 148. A pharmaceutical composition for the treatment of diabetes or hyperglycaemia in a patient in need of such treatment, comprising a therapeutically effective amount of a crystal according to paragraph 1 , 74, 75 or 111 and optionally pharmaceutically acceptable excipients.

149. A pharmaceutical composition according to paragraph 148 comprising a phar- maceutically acceptable carrier.

150. A pharmaceutical composition for according to paragraphs 148-150, wherein the composition comprises a crystal according to paragraphs 1 , 74, 75 or 111 in admixture with a human insulin, an insulin analogue, an insulin derivative or a mixture thereof.

151. A pharmaceutical composition for according to paragraphs 148-150, wherein the insulin analogue has a rapid onset of action.

152. A pharmaceutical composition for according to paragraphs 148-151 , wherein the insulin analogue is selected from the group consisting of AspB28 human insulin; LysB28ProB29 human insulin, GlyA21ArgB31ArgB32 human insulin and LysB3GluB29 human insulin. 153. A pharmaceutical composition according to any of paragraphs 148-152, wherein the composition is a powder or a granule.

154. A pharmaceutical composition according to any of paragraphs 148-152, wherein the composition is a suspension.

155. A method of treating diabetes or hyperglycaemia in a patient in need of such a treatment by the use of a therapeutically effective amount of a crystal according to paragraph 1 ,

74, 75 or paragraph 11 1 or a pharmaceutical composition according to paragraph 148.

156. A method according to paragraph 155, comprising using the crystal according to paragraph 1 , 74, 75 or 111 or a pharmaceutical composition according to paragraph 148 in admixture with a human insulin, an insulin analogue, an insulin derivative or a mixture thereof. 157. A method according to paragraphs 155-156, wherein the insulin analogue has a rapid onset of action.

158. A method according to paragraphs 155-157 for pulmonary treatment of diabetes or hyperglycaemia.

159. A method according to paragraphs 155-157 for parenteral treatment of diabetes or hyperglycaemia.

160. A method according to paragraphs 155-157 for nasal treatment of diabetes or hyperglycaemia.

161. Use of a crystal according to paragraph 1 ,74,75 or 111 for the manufacture of a pharmaceutical composition for the use in the treatment of type 1 diabetes, type 2 diabetes and other states that cause hyperglycaemia. 162. Use of a crystal according to paragraph 161 in mixture with human insulin, an insulin analogue, an insulin derivative or a mixture thereof.

163. Use according to paragraphs 161-162, wherein the insulin analogues have a rapid onset of action. 164. Use according to paragraph 161-163, wherein the insulin analogue is selected from the group consisting of AspB28 human insulin; LysB28ProB29 human insulin, GlyA21ArgB31ArgB32 human insulin and LysB3GluB29 human insulin. 165. Insulin crystal as described in the examples.

All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference in their entirety and to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein (to the maximum extent permitted by law).

All headings and sub-headings are used herein for convenience only and should not be construed as limiting the invention in any way.

The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the inven- tion.

The citation and incorporation of patent documents herein is done for convenience only and does not reflect any view of the validity, patentability, and/or enforceability of such patent documents.

This invention includes all modifications and equivalents of the subject matter re- cited in the claims appended hereto as permitted by applicable law.

The present invention is further illustrated by the following examples which, however, are not to be construed as limiting the scope of protection.

DRAWINGS Figure 1 : Insulin crystals in space group C222-_I (as determined by X-ray diffraction).

Picture is taken through a light microscope with 20 fold magnification. EXAMPLES

Example 1

Preparation of a solution containing insulin, zinc, resorcinol and thiocyanate: An insulin solution is prepared by adding 15 mg of zinc free freeze dried insulin to

1.5 ml of a 50 mmol/l phosphate buffer which is adjusted to pH 9.2. The insulin is subsequently filtered through a filter with a pore size of 0.45 μm. The final concentration is determined by UV spectroscopy to be 8.7 mg/ml. To 1.5 ml of the insulin solution is added 77 μl of a 10 mmol/l zinc acetate solution, which corresponds to a zinc content of 2.3 Zn per 6 insulin molecules. To 1.5 ml of the zinc-insulin solution is added 15 μl of an aqueous resorcinol solution with a concentration of 2 mol/l and 45.5 μl of an aqueous solution of sodium thiocyanate with a concentration of 1 mol/l.

Example 2 Preparation of insulin crystals in space group C2.

To 1.5 ml of a solution as prepared in example 1 is added 900 μl water, 525 μl of a phosphate solution with a pH of 7.0 and a concentration of 2 mol/l and 75 μl of ethanol. Characteristically shaped crystals appeared within 24 h at room temperature.

Example 3

Preparation of insulin crystals in space group C222-_I.

To 1.5 ml of a solution as prepared in example 1 is added 900 μl water, 525 μl of a phosphate solution with a pH of 6.0 and a concentration of 2 mol/l and 75 μl of ethanol. Characteristically shaped crystals appeared within 24 h at room temperature (see Figure 1 ).

Example 4

Crystals comprising phenol in space group C2.

An insulin solution is prepared by adding 18 mg of zinc free freeze dried insulin to 750 μl of a 50 mmol/l phosphate (pH 9.2). To this insulin solution is added 100 μl of a 10 mmol/l zinc acetate solution, 42.5 μl of a solution of phenol in ethanol with a concentration of 2 mol/l and 36 μl of a solution containing sodium thiocyanate at a concentration of 1 mol/l. To 200 μl of this solution is added 50 μl of a solution containing 350 mmol/l phosphate and 50 mmol/l phenol. The solution is mixed and the pH adjusted to pH 7.0.

Crystals belonging to space group C2 appeared within 12 h at room temperature. Example 5

Determination of space group and unit cell constants.

Space group and cell constants are determined by X-ray diffraction experiments. a.) Single crystal diffraction method Single crystals were flash frozen and mounted on a Rigaku rotating anode generator

(RU200) equipped with a MarResearch imaging plate. Diffraction data were collected using the rotation method (U. W. Arndt and AJ. Wonacott. The rotation method in crystallography. Amsterdam: North-Holland, 1977). Space group and unit cell parameters were determined using the HKL2000 (Otwinowski. Z. & Miner, W., Methods in Enzymology 276, p. 307-326, 1997) or XDS (Kabsch, W., J. Appl. Cryst. 26, p.795-800, 1993) computer programs.

b.) Powder diffraction method

Crystals were transferred to bottom capped glass capillaries for x-ray powder diffraction. The samples were centrifuged at 1500 g for 15 min to pack the crystals in the bot- torn of the capillary. Data were collected at room temperature using a rotating anode generator (Rigaku RU200, Osmic mirrors, Cu-Ka radiation, λ = 1.5418 A) with a Mar345 image plate detector during 5400 sec exposure time and 360° φ-rotation. The powder pattern intensities in the 2Θ range 0.9° - 10° were integrated by summation in the χ region 0° - 360° using the Datasqueeze software (P. A. Heiney, Commission on Powder Diffraction Newsletter 32, p. 9- 11 ,2005). The resulting intensity versus 2Θ plots were saved as xy-files in ASCII-format and imported into the WinPrep program (Stahl, in house program) for background correction and curve smoothing. All intensities were normalized against total intensity with in house software. By comparison of the powder patterns with a set of standard pattern is it possible to assign the microcrystalline to a known space group as described in Norrman et al., J. Appl. Cryst. (2006) 39, 391-400.

Example 6

Stability studies

The objective of this study was to determine the stability of the new insulin crystals in space groups C2 and C222i. Suspensions of insulin crystals in space group C2 and C222i were obtained as follows: To 2 ml of a solution containing 17.7 mg/ml insulin, 60 mM phenol, 1.4 mM Zn-acetate and 15 mM sodium thiocyanate was added 500 μl of a solution containing 2M sodium phosphate adjusted to pH 5.8 (for crystals in space group C222-ι) or pH 7.0 (crystals in space group C2), respectively. Crystallisation was complete within 12 hours.

The crystal suspensions were frozen at - 18 °C and lyophilised for 20 hours in order to obtain dry crystals.

To test the stability of the insulin they were stored for 2 weeks at +40 °C prior to analysis. These storage conditions are severe compared to storage at +2 to +8 °C. As a control, rhombohedral human insulin crystals, space group R3 (Schlichtkrull, J: Insulin crystals, Munksgaard, 1958, Copenhagen), was stored under the same conditions.

The chemical stability was demonstrated using size-exclusion chromatography for determination of "Impurities with molecular masses greater than that of insulin".

The results are presented in Table 1.

Table 1 List of results after storage at +40 ⁰C for 2 weeks.

It is apparent that the new insulin crystal forms are more chemically stable than the control.

Claims

1. A crystal comprising insulin wherein the crystal being grown in the presence of a chaotropic agent provided that the crystal is not grown in the presence of urea.

2. Crystal according to claim 1 , wherein the crystal belongs to space group C222-_I with a unit cell constants of a=59 A b=220 A c=225 A α=β=γ=90° or space group C2 with a unit cell constant of a=101 A b=61 A c=63 A α=90° β=1 16° γ=90° when determined by X-ray diffraction.

3. Crystal according to claim 1 and 2, wherein the crystal comprises zinc.

4. Crystal according to claims 1-3, wherein the crystal also comprises a phenolic agent, wherein the phenolic agent is selected from the group consisting of resorcinol, cresol, meta-cresol, phenol, methyl p-hydroxybenzoate and methyl 4-hydroxybenzoate.

5. Crystal according to claims 1-4, wherein the chaotropic agent belongs to the group of alkali metal salts of thiocyanate or arginine, wherein the alkali metal salts of thiocy- anate can be sodium thiocyanate or potassium thiocyanate.

6. Crystal according to any of the preceding claims, wherein at least 50% of the crystals are in the range of the range of 1-30 μm.

7. Crystal according to any of the preceding claims, wherein at least 50% of the crystals are in the range of the range of 1-20 μm.

8. Crystal according to any of the preceding claims, wherein at least 50% of the crystals are in the range of the range of 1-10 μm.

9. Crystal according to any of the preceding claims, wherein at least 50% of the crystals are in the range of the range of 1-5 μm, for example 1-3 μm.

10. Crystal according to any of the preceding claims, wherein the insulin is human insulin, porcine insulin or an insulin analogue.

1 1. A process for preparing a crystal comprising insulin by providing an aqueous solution comprising: a) insulin b) zinc c) a phenolic agent d) a chaotropic agent and adjusting the pH of the solution to a pH in the range of 5,8-8,0 and allowing the insulin in the solution to crystallize, with the provision that the chaotropic agent is not urea.

12. A process according to claim 11 , wherein the solution of insulin is present in a concentration of 0.5 mg/ml to 250 mg/ml.

13. Process according to claims 1 1-12, wherein a precipitant is added to the solution before it is allowed to crystallize, or a precipitant is added to the solution before and while it is allowed to crystallize.

14. Process according to claims 1 1 and 13, wherein the precipitant is an alcohol or a salt.

15. Process according to claims 1 1-14, wherein the phenolic agent is selected from the group consisting of resorcinol, cresol, meta-cresol, phenol, methyl p-hydroxybenzoate and methyl 4-hydroxybenzoate.

16. Process according to claims 1 1-15, wherein the chaotropic additive is arginine or belongs to the group of alkali metal salts of thiocyanate.

17. Process according to any of claims 11-18, wherein the pH is adjusted so the pH of the solution is in the range of about 6.0 to about 6.8, about 6.2 to about 6.6 or about 6.2 to about 6.4.

18. Process according to any of claims 11-17, wherein the pH is adjusted so the pH of the solution is approximately 6.3.

19. Process according to any of claims 11-16, wherein the pH is adjusted so the pH of the solution is in the range of about 6.2 to about 7.8, about 6.5 to about 7.5, about 6.8 to about 7.2 or about 6.9 to about 7.1.

20. Process according to any of claims 11 -16 or claim 19, wherein the pH is adjusted so the pH of the solution is approximately 7.0

21. Insulin crystal produced by the process of claims 1 1-20.

22. A pharmaceutical composition for the treatment of diabetes or hyperglycaemia in a patient in need of such treatment by the use of an effective amount of a crystal according to claim 1 or claim 21.

23. A pharmaceutical composition according to any of claim 22, wherein the composi- tion is a powder or a granule.

24. A method of treating diabetes or hyperglycaemia in a patient in need of such a treatment, comprising administering to the patient a therapeutically effective amount of a crystal according to claim 1 or claim 21 or a pharmaceutical composition according to claim 22.

25. A method according to claim 24 for pulmonary, parenteral or nasal treatment of diabetes or hyperglycaemia.

26. Insulin crystal as described in the examples.