PARTICULATE PHARMACEUTICAL COMPOSITIONS AND DOSAGE FORMS OF SAXAGLIPTIN AND METHODS FOR MAKING THE SAME

CROSS REFERENCES TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial Number 62/064,089, filed on October 15, 2014, which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

[0002] The present disclosure relates generally to pharmaceutical compositions and methods for making them. More particularly, in certain aspects the present disclosure relates to methods for making formulations of saxagliptin.

2. Technical Background

[0003] The compound saxagliptin has the structure

[0004] It is known to be an orally active reversible dipeptidyl peptidase-4 (DPP- IV) inhibitor, as disclosed in U.S. Patent No. 6,395,767. After a meal intake, insulinotropic hormone GLP-1 is released which in turn induces insulin release from the pancreas. Some of the GLP-1 is inactivated by the DPP-IV present in plasma and intestinal capillary endothelium. Therefore, if the DPP-IV is inhibited, more GLP-1 will be available to activate insulin release from the pancreas. The advantage of this mechanism of insulin release is that insulin is secreted only in response to a meal. Therefore, problems of hypoglycemia associated with other diabetes drugs will be less likely with a DPP-IV inhibitor. Saxagliptin is available (in the form of a

hydrochloride salt form) under the trade name ONGLYZA ^® as a therapeutic agent for treatment of Type-2 diabetes mellitus.

[0005] Saxagliptin is a labile compound, prone to an intra-molecular cyclization as shown below.

DPP4-inhibitor Cyclic amidine

[0006] The resulting degradation product is a cyclic amidine (mainly cis-cyclic amidine (CA)), which is not therapeutically active and therefore, its formation is not desirable. This cyclization reaction can occur both in solid state and solution state. The rate of intra-molecular cyclization is accelerated when formulations are subject to the forces inherent in commonly-used processing activities such as wet granulation, roller compaction, or tabletting. Given these properties of the molecule, manufacture of a conventional tablet dosage form for the DPP4-inhibitor, which is a preferred dosage form, is difficult to achieve. In fact, it has been found that using conventional granulation and compression processes to form tablets of saxagliptin HC1 results in the generation of an unacceptable level of impurities.

[0007] Currently, saxagliptin is provided in the form of a coated tablet, in which saxagliptin is provided in the coating of the tablet, as opposed to in the tablet core itself. The manufacture of such coated tablets uses a spray coating process, in which the saxagliptin is dissolved in acidic aqueous media together with a coating polymer and then sprayed onto the surface of the core tablet, as described in U. S. Patent no. 7,9514,00. This spray coating process avoids the undesirable mechanical forces of common tabletting processes, but requires expensive spray coating equipment and involves many process steps and extended drying times.

SUMMARY OF THE DISCLOSURE

[0008] One aspect of the disclosure is a method for making a particulate pharmaceutical composition comprising an saxagliptin in a second crystalline hydrohalide salt form; and one or more polymers, the method comprising:

providing a solution of the one or more polymers in a solvent for the one or more polymers, the solvent not significantly dissolving saxagliptin, the solution of the one or more polymers including hydrohalic acid; adding to the solution of the one or more polymers saxagliptin in a free base form, under conditions sufficient to convert the free base form of saxagliptin to a first crystalline hydrohalide salt form of saxagliptin, the first crystalline hydrohalide salt form of the saxagliptin being present in slurry form in the solution of the one or more polymers;

adding an anti solvent for the one or more polymers to the slurry of the first

crystalline hydrohalide salt form of saxagliptin in the solution of the one or more polymers, in an amount and under conditions sufficient to precipitate the one or more polymers onto the first crystalline hydrohalide salt form of saxagliptin to form a slurry of particles, each particle comprising the one or more polymers and the first crystalline hydrohalide salt form; and

recovering the particles from the slurry to yield the particulate pharmaceutical composition.

[0009] One particular aspect of the disclosure is a method for making a particulate pharmaceutical composition comprising saxagliptin in a second crystalline HC1 salt form; and one or more polymers, the method comprising:

providing a solution of the one or more polymers in a solvent for the one or more polymers, the solvent not significantly dissolving the saxagliptin, the solution of the one or more polymers including HC1;

adding to the solution of the one or more polymers the saxagliptin in a free base form, under conditions sufficient to convert the free base form of the saxagliptin to a first crystalline HC1 salt form of the saxagliptin, the first crystalline HC1 salt form of the saxagliptin being present in slurry form in the solution of the one or more polymers;

adding an anti solvent for the one or more polymers to the slurry of the first

crystalline HC1 salt form of the saxagliptin in the solution of the one or more polymers, in an amount and under conditions sufficient to precipitate the one or more polymers onto the first crystalline HC1 salt form of the saxagliptin to form a slurry of particles, each particle comprising the one or more polymers and the first crystalline HC1 salt form of the saxagliptin; and

recovering the particles from the slurry to yield the particulate pharmaceutical composition. [0010] Another aspect of the disclosure is a particulate pharmaceutical composition including a plurality of particles, each particle including saxagliptin in a crystalline hydrohalide (e.g., HC1) salt form and one or more polymers.

[0011] Another aspect of the disclosure is a method for making a tablet dosage form comprising saxagliptin in a crystalline hydrohalide (e.g., HC1) salt form; and one or more polymers, the method comprising

providing the particulate pharmaceutical composition made as described herein, or the particulate pharmaceutical composition as described herein;

optionally combining the particulate pharmaceutical composition with one or more excipients and/or one or more additional active pharmaceutical ingredients; and

compressing the particulate pharmaceutical composition, one or more optional additional excipients and one or more optional additional active

pharmaceutical ingredients into the tablet dosage form; provided that when the one or more excipients are silicon dioxide based excipients the excipients are present in amount no more than 1.5 wt%, preferably, less than 1.5 wt %.

[0012] Another aspect of the disclosure is a tablet dosage form including a compressed layer that includes, in compressed form, a particulate pharmaceutical composition as described herein; optionally one or more additional excipients; and optionally one or more additional active pharmaceutical ingredients, provided that when the one or more excipients are silicon dioxide based excipients the excipients are present in amount no more than 1.5 wt%, preferably, less than 1.5 wt %.

[0013] Another aspect of the disclosure is a tablet dosage form including a compressed layer that includes, in compressed form, a particulate pharmaceutical composition as described herein; optionally one or more additional excipients;

optionally one or more additional active pharmaceutical ingredients, and a stabilizing agent, provided that when the one or more excipients are silicon dioxide based excipients the excipients are present in amount no more than 1.5 wt%, preferably, less than 1.5 wt %.

[0014] Another aspect of the disclosure is a tablet dosage form wherein the stabilizing agent is alginic acid. [0015] Another aspect of the disclosure is a tablet dosage form including a compressed layer that includes, in compressed form, a particulate pharmaceutical composition as described herein; optionally one or more additional excipients; and optionally one or more additional active pharmaceutical ingredients, provided that when the one or more excipients are silicon dioxide based excipients the excipients are present in amount no more than 1.5 wt%, preferably, less than 1.5 wt %.

[0016] Various embodiments of the disclosure can result in one or more advantages over conventional methods and pharmaceutical compositions. As described in more detail below, the methods used to make the particulate

pharmaceutical compositions described herein can be performed in a single unit operation using standard crystallization equipment. The particulate compositions can be compressed into tablets, thus providing a more simply formed tablet dosage formed as compared to the spray-coated dosage forms currently being used. Thus, in certain embodiments, tablet dosage forms can be made more cheaply than the current commercial coated tablets. As opposed to a crystalline saxagliptin HC1 salt form itself, in the particulate pharmaceutical compositions described herein the polymer can provided physical protection against the mechanical forces encountered in tabletting that can lead to chemical degradation. And the fact that the saxagliptin is provided in a highly crystalline form impedes intramolecular degradation.

Accordingly, the particulate pharmaceutical compositions can be used to make tablets that have satisfactory stability profiles and shelf life.

[0017] Various aspects of the disclosure will be further described with reference to embodiments depicted in the appended drawings. It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of embodiments of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are not necessarily to scale, and sizes of various elements can be distorted for clarity.

[0019] FIG. 1 is a powder X-ray diffraction pattern of the H-l form of saxagliptin free base monohydrate; [0020] FIG. 2 is a powder X-ray diffraction pattern of the H2-1 form of saxagliptin mono HC1 dihydrate;

[0021] FIG. 3 is a powder X-ray diffraction pattern of the HO.75-3 form of saxagliptin mono HC1 0.75 hydrate;

[0022] FIG. 4 is a process flow diagram depicting one example of a method according to the present invention;

[0023] FIG. 5 is a micrograph of saxagliptin HC1 crystals in slurry form as formed in the method described with respect to FIG. 4;

[0024] FIG. 6 is a micrograph of saxagliptin HCl/poly(vinyl pyrrolidone-co-vinyl acetate) (PVPVA 64) particles in slurry form as formed in the method described with respect to FIG. 4;

[0025] FIG. 7 is a powder X-ray diffraction pattern of the saxagliptin

HCl/poly(vinyl pyrrolidone-co-vinyl acetate) particles of FIG. 6 (top), as compared to the powder X-ray diffraction pattern of the H2-1 form of saxagliptin HC1 dihydrate (bottom);

[0026] FIG. 8 is a powder X-ray diffraction pattern of the dried saxagliptin HCl/poly(vinyl pyrrolidone-co-vinyl acetate) particulate pharmaceutical composition as described with respect to FIG. 4 (top), as compared to the powder X-ray diffraction pattern of the saxagliptin mono HC1 0.75 hydrate HO.75-3 form (bottom);

[0027] FIG. 9 is a graph of the particle size distribution of the dried saxagliptin HCl/poly(vinyl pyrrolidone-co-vinyl acetate) particulate pharmaceutical composition as described with respect to FIG. 4;

[0028] FIGS. 10A, 10B, IOC and 11 are Raman images of a particle of the dried saxagliptin HCl/poly(vinyl pyrrolidone-co-vinyl acetate) particulate pharmaceutical composition as described with respect to FIG. 4;

[0029] FIG. 12 is a graph of storage stability data for compressed tablets made using the particulate pharmaceutical composition described with respect to FIG. 4, in which each set of bars, from left to right, presents data for TO (initial), 4 weeks, 3 months and 6 months;

[0030] FIG. 13 is a flowchart depicting another example of a method according to the present invention; [0031] FIG. 14 is a graph of storage stability data for compressed tablets made using the particulate pharmaceutical composition described with respect to FIG. 13, in which each set of bars, from left to right, presents data for TO, 2 weeks and 6 months;

[0032] FIG. 15 is a graph of storage stability data for compressed tablets made using the particulate pharmaceutical composition described with respect to FIG. 13, in which each set of bars, from left to right, presents data for TO, 2 weeks and 4 weeks;

[0033] FIG. 16 is a powder X-ray diffraction pattern of the P-4 form of saxagliptin hydrochloride, and of a particulate pharmaceutical composition according to one embodiment of the present invention;

[0034] FIG. 17 is a flowchart depicting another example of a method according to the present invention;

[0035] FIG. 18 is a powder X-ray diffraction pattern of a particulate

pharmaceutical composition according to one embodiment of the present invention, of the Q-l form of saxagliptin hydrochloride, and of the mono HC1 0.75 hydrate form H0.75-3;

[0036] FIG. 19 is a flowchart depicting another example of a method according to the present invention;

[0037] FIG. 20 is a powder X-ray diffraction pattern of a particulate

pharmaceutical composition according to one embodiment of the present invention, of the Q-l form of saxagliptin hydrochloride, and of the mono HC1 0.75 hydrate form H0.75-3; and

[0038] FIG. 21 is a flowchart depicting another example of a method according to the present invention;

[0039] FIG 22 is a flowchart depicting another example of a method according to the present invention;

[0040] FIG. 23 is a graph showing the formation of cyclic amidine (A) and total (B) saxagliptin impurities is plotted for direct compression (DC) and roller compaction (RC) batches prepared with and without alginic acid (AA);

[0041] FIG. 24 is a graph showing the formation of cyclic amidine (A) and total (B) saxagliptin impurities is plotted for the roller compaction (RC) batch prepared with alginic acid (AA); [0042] FIG. 25 is a graph showing formation of cyclic amidine (A) and total (B) saxagliptin impurities is plotted for the direct compression (DC) and roller compaction (RC) batch prepared with alginic acid (AA);

[0043] FIG.26 a graph showing water activity of bilayer core and coated tablets of saxagliptin CPT/dapagliflozin/metformin extended release (XR) fixed dose combination;

[0044] FIG. 27 is a flowchart depicting another example of a method according to the present invention;

[0045] FIG. 28 is a graph showing the concentration of cyclic amidine and cyclic amidine epimer in saxagliptin CPT/dapagliflozin monolithic core tablets after 4 weeks of storage at 40°C/75% RH in induction sealed HDPE bottles with desiccants; and

[0046] FIG. 29 is a table showing cyclic amidine impurities after storage for 2 weeks at 40°C.

DETAILED DESCRIPTION

[0047] In one aspect, the disclosure provides a method for making a particulate pharmaceutical composition comprising saxagliptin in a second crystalline HCl salt form; and one or more polymers. The method includes providing a solution of the polymer in a solvent for the one or more polymers. Notably, the solvent does not significantly dissolve the saxagliptin, neither in the free base form nor in any HCl salt form (e.g., in certain embodiments, the active pharmaceutical ingredient and its HCl salts have a solubility in the solvent of less than about 10 mg/mL, or even less than about 1 mg/mL). To this solution of the one or more polymers is added the saxagliptin in free base form (e.g., as a solid, such as a crystalline solid), under conditions sufficient to convert the free base form of the saxagliptin to a first crystalline HCl salt form of the saxagliptin. Thus, the first crystalline HCl salt form of the saxagliptin is present in slurry form in the solution of the one or more polymers. To the slurry of the first crystalline HCl salt form of the saxagliptin in the solution of the one or more polymers is added an antisolvent for the one or more polymers, in an amount and under conditions sufficient to precipitate the one or more polymers onto the first crystalline HCl salt form of the saxagliptin to form a slurry of particles. The particles are then recovered from the slurry to yield the particulate pharmaceutical composition. [0048] In certain embodiments of the methods described herein, the slurry of the particles is wet milled, for example in order to provide a desired particle size to the particulate pharmaceutical composition. For example, the wet milling can be performed substantially simultaneously with the addition of the antisolvent. Of course, in other embodiments, the wet milling can be performed after the addition of the antisolvent.

[0049] The particles can be recovered from the slurry in any of a number of ways. In one embodiment, the recovering the particles from the slurry includes separating a substantial amount of the liquid from the slurry of the particles; washing the particles with a wash liquid; and separating the particles from all liquid. For example, most or all of the solvent/anti solvent liquid mixture can be separated from the particles using any of a variety of techniques familiar to the person of skill in the art, including, for example, centrifugation, filtration, and decanting. The separated particles can then be washed with a wash liquid and then dried, as described in further detail below.

[0050] Certain particular embodiments of the methods and compositions of the invention are described herein with respect to saxagliptin. The free base form of the saxagliptin can be provided as a solid. The free base form can be an amorphous form, or can be a crystalline form, and can include water of hydration or other solvate molecules. The preparation of saxagliptin can be generally described in U.S. Patent 6,395,767 (see, e.g., Example 60) and in U.S. Patent Application Publication no. 2005/0090539 Al (see, e.g., Schemes VII and VIIB and Examples 41 and 42). Each of U.S. Patent 6,395,767 and U.S. Patent Application Publication US2005/0090539 Al is hereby incorporated by reference herein in its entirety.

[0051] In certain embodiments of the methods described herein, the second crystalline HCl salt form (i.e., the form in the particulate pharmaceutical composition) is the same as the first crystalline HCl salt form (i.e., the form present at the time the polymer is precipitated). In other embodiments, the second crystalline HCl salt form (i.e., the form in the particulate pharmaceutical composition) is different than the first crystalline HCl salt form (i.e., the form present at the time the polymer is

precipitated). In certain circumstances, the crystalline form can change during processing, for example, during drying of the particles to form the particulate pharmaceutical composition. [0052] In certain embodiments, the free base of the saxagliptin is provided in the form of a hydrate, for example, as a saxagliptin free base monohydrate. In certain embodiments, the saxagliptin free base monohydrate is provided in the crystalline form H-1, as described in U.S. Patent no. 7,943,656, which is hereby incorporated herein by reference in its entirety. The H-1 form can be made in a variety of ways, as described in U.S. Patent no. 7,943,656, examples of which are provided below.

[0053] A first process for preparing crystalline saxagliptin in the form of the monohydrate of its free base (form H-1) includes the steps of:

(a) providing the Boc-protected form of saxagliptin having the structure

(see U.S. Patent Application Publication no. 2005/0090539);

(b) dissolving the protected saxagliptin from step (a) in an organic solvent such as ethyl acetate, isopropyl acetate or methyl tetrahydrofuran preferably ethyl acetate;

(c) reacting the solution from step (b) with a strong mineral acid such as hydrochloric acid, phosphoric acid or sulfuric acid, preferably hydrochloric acid;

(d) if necessary, adding organic solvent such as described in step (b) to the reaction mixture from step (c);

(e) cooling the reaction mixture to a temperature within the range from about 5 to about 35°C, preferably from about 15 to about 25°C;

(f) treating the cooled mixture from step (e) with base, such as potassium carbonate, potassium bicarbonate, or sodium hydroxide, preferably anhydrous potassium carbonate;

(g) filtering the mixture from step (f) to separate the solids from filtrate;

(h) optionally, washing the solids with organic solvent (as set out in step

(b));

(i) collecting and concentrating filtrate;

G) if necessary, adding water to the filtrate;

(k) agitating the filtrate until crystals form;

(1) optionally, repeating step (j); (m) optionally, agitating the filtrate; and

(n) recovering crystals of saxagliptin free base monohydrate (form H-l) in substantially pure form.

[0054] A second process for preparing crystalline saxagliptin in the form of the monohydrate of its free base (form H-l) includes the steps of:

(a) providing the Boc-protected saxagliptin (IA);

(b) reacting a mixture of the Boc-protected saxagliptin (IA) with an organic solvent such as methylene chloride, l,2-dichloroethane,or chlorobenzene preferably methylene chloride, an alcohol such as methanol, ethanol or isopropanol, preferably methanol, with a strong mineral acid, such as hydrochloric acid, , phosphoric acid or sulfuric acid, preferably hydrochloric acid, during which an aqueous phase and an organic phase form;

(c) collecting the aqueous phase;

(d) mixing the aqueous phase with organic solvent such as used in step (b), preferably methylene chloride, water, and then strong base such as an alkali metal base, such as sodium hydroxide or potassium hydroxide, preferably sodium

hydroxide, to adjust pH to within the range from about 8.8 to about 10.8, preferably from about 9.0 to about 10.5;

(e) adding sodium chloride to the reaction mixture;

(f) mixing the reaction mixture, whereby an aqueous phase and an organic phase form;

(g) optionally, washing the organic layer with a salt or brine solution such as ammonium chloride brine solution to form an aqueous layer and an organic layer;

(h) treating the organic layer with an organic solvent such as ethyl acetate, isopropyl acetate or methyl tetrahydrofuran, preferably ethyl acetate, while distilling off a portion of organic solvent such as methylene chloride;

(i) filtering the remaining distillation product to remove sodium chloride; (j) concentrating the filtrate to obtain approximately 1 g saxagliptin per 10 mL of ethyl acetate;

(k) adding water to the mixture from step (j) until crystallization begins; (1) optionally, adding additional water to form a slurry;

(m) optionally, mixing the slurry;

(n) filtering the slurry; (0) optionally, washing the resulting wet cake with an organic solvent as defined in step (h), preferably ethyl acetate;

(p) drying the wet cake under vacuum to obtain crystalline saxagliptin in the form of the monohydrate of its free base (form H-l); and

(q) recovering the crystalline saxagliptin monohydrate form H-l in substantially pure form.

[0055] In yet another embodiment of the present invention, a third process for preparing crystalline saxagliptin in the form of the monohydrate of its free base (form H-l) is provided which includes the steps of:

(a) providing the Boc-protected form of saxagliptin (IA);

(b) heating the Boc-protected form of saxagliptin (IA) in a water miscible organic solvent such as isopropanol, methanol, or acetonitrile, preferably isopropanol, water and concentrated mineral acid such as hydrochloric acid, phosphoric acid, or methanesulfonic acid, preferably hydrochloric acid, at a temperature within the range from about 55 to about 75°C, preferably from about 60 to about 70°C;

(c) adding water to the heated mixture;

(d) cooling the mixture from step (c) to a temperature within the range from about 15 to about 35°C, preferably from about 20 to about 30°C;

(e) adding to the cooled mixture an organic solvent such as methylene chloride, 1,2-dichloroethane or chlorobenzene, preferably methylene chloride, and adjusting the pH of the mixture to within the range from about 8 to about 10, preferably from about 8.5 to about 9.5 (using a base such as an alkali metal hydroxide, for example, sodium hydroxide, or potassium hydroxide preferably sodium hydroxide and potassium carbonate);

(f) dissolving sodium chloride in the pH adjusted solution which forms two phases;

(g) separating the two phases and collecting the rich organic phase;

(h) concentrating the rich organic phase to remove residual water;

(1) cooling the organic phase to a temperature within the range from about 15 to about 35°C, preferably from about 20 to about 30°C;

(j) adding ethyl acetate or other organic solvent such as isopropyl acetate, or methyl tetrahydrofuran, preferably ethyl acetate, to the cooled mixture;

(k) filtering the resulting solution to remove residual sodium chloride; (1) adding water to the solution, and upon standing, to form crystals of saxagliptin free base monohydrate; and

(m) recovering crystals of saxagliptin free base monohydrate in

substantially pure form.

[0056] Crystals of saxagliptin free base monohydrate (form H-l) may be recovered in step (m) above according to the following steps:

(a) adding water to the product in step (m);

(b) performing constant volume distillation at less than about 30°C by adding ethyl acetate at approximately the rate of distillation;

(c) adding water to the mixture from step (b) and cooling to a temperature within the range from about 0 to about 15°C, preferably from about 0 to about 10°C;

(d) filtering solids from the mixture;

(e) washing the resulting cake with a mixture of organic solvent such as ethyl acetate, isopropyl acetate, or methyl tetrahydrofuran, preferably ethyl acetate, and water;

(f) drying at about 30 to about 50°C, preferably from about 35 to about 45°C while maintaining the dewpoint about -8°C; and

(g) recovering crystals of the saxagliptin free base (form H-l)

monohydrate in substantially pure form.

[0057] A powder x-ray diffraction pattern for form H-l is provided as FIG. 1. The saxagliptin free base monohydrate (form H-l) can be characterized, for example, by powder X-ray diffraction pattern characteristic peak positions comprising the following 2Θ values (CuKa λ - 1.5418 A) 12.4 ± 1, 13.3 ± 1, 13.6 ± 1, 14.7 ± 1, 16.2 ± 1, 18.2 ± 1, 19.9 ± 1, 20.9 ± 1, 21.9 ± 1 and 22.4 ± 1 at about room temperature. Alternatively or additionally, the saxagliptin free base monohydrate (form H-l) can be characterized by unit cell parameters substantially equal to the following:

Cell dimensions for single crystal

a = 7.270(1) A

b= 14.234(1) A

c = 16.929(1) A

a = 90°

β = 90° γ = 90°

Space group P2 2 2

Molecules/asymmetric unit 1

wherein said crystalline form is at about 22 °C. Alternatively or additionally, the saxagliptin free base monohydrate (form H-1) can be characterized by a powder x-ray diffraction pattern substantially equal to that in FIG. 1. Alternatively or additionally, the saxagliptin free base monohydrate (form H-1) can be characterized as described in U.S. Patent no. 7,943,656.

[0058] In certain embodiments, the first saxagliptin crystalline HCl salt form is a saxagliptin monohydrochloride salt. For example, in one embodiment, the first crystalline HCl salt form is the saxagliptin monohydrochloride salt dihydrate form H2-1, as described in U.S. Patent no. 7,943,656. The mono HCl dihydrate H2-1 form is a dihydrate of saxagliptin HCl that includes one equivalent of HCl and two equivalents of water of hydration. U.S. Patent no. 7,943,656 describes methods for preparing samples of the mono HCl dihydrate H2-1 form; one particular example is described below.

[0059] A comparative sample of mono HCl dihydrate H2-1 form can be made, for example, by a process which includes the steps of:

(a) providing saxagliptin in the form of its trifluoroacetic acid salt;

(b) dissolving the salt from step (a) in water;

(c) adjusting the pH of the resulting aqueous solution to a pH within the range from about 9 to about 9.8, preferably from about 9.2 to about 9.6 with a strong base such as an alkali metal hydroxide, such as sodium hydroxide or potassium hydroxide, preferably sodium hydroxide, to form an aqueous phase and an organic phase;

(d) treating the resulting solution from step (c) with an organic solvent such as methylene chloride, 1,2-dichloroethane or chlorobenzene, preferably methylene chloride, to extract the aqueous layer from the rich methylene chloride (organic solvent) layer;

(e) adding a solution of hydrochloric acid to the rich organic (methylene chloride) solution;

(f) evaporating the organic (methylene chloride) solution to dryness; (g) dissolving the resulting solids from step (f) in an alcohol solvent such as ethanol, methanol or isopropanol, preferably ethanol;

(h) heating the alcohol (ethanol) solution from step (g) to a temperature within the range from about 35 to about 60°C, preferably from about 40 to about

50°C;

(i) adding t-butylmethyl ether (MTBE) or other slurrying agent, such as ethyl acetate or isopropyl acetate, to the heated solution from step (h) to form a slurry;

(j) cooling the resulting slurry;

(k) filtering the slurry;

(1) drying the resulting wet cake to obtain crystals of saxagliptin dihydrate in the form of its hydrochloride salt (form H2-1); and

(m) recovering the crystals of saxagliptin dihydrate of its mono HCl salt in substantially pure form.

[0060] A powder x-ray diffraction pattern for mono HCl dihydrate form H2-1 is provided as FIG. 2. The saxagliptin mono HCl dihydrate form H2-1 can be characterized, for example, by powder X-ray diffraction pattern characteristic peak positions comprising the following 2Θ values (CuKa λ - 1.5418 A) 6.8 + 0.1, 11.1 ± 0.1, 13.7 ± 0.1, 14.6 ± 0.1, 15.2 ± 0.1, 16.4 ± 0.1, 17.0 ± 0.1, 20.2 ± 0.1 and 21.1 ± 0.1 at about room temperature. Alternatively or additionally, the saxagliptin mono HCl dihydrate form H2-1 can be characterized by unit cell parameters substantially equal to the following:

Alternatively or additionally, the mono HCl dihydrate form H2-1 can be characterized by a powder x-ray diffraction pattern substantially equal to that in FIG. 2.

Alternatively or additionally, the mono HCl dihydrate form H2-1 can be characterized as described in U.S. Patent no. 7,943,656. [0061] In certain embodiments, the second crystalline saxagliptin HCl salt form is a saxagliptin monohydrochloride salt. For example, in one embodiment, the second crystalline HCl salt form is the saxagliptin monohydrochloride salt 0.75 hydrate form HO.75-3, as described in U.S. Patent no. 7,943,656. The mono HCl 0.75 hydrate form HO.75-3 includes one equivalent of HCl and 0.75 equivalents of water of hydration. U.S. Patent no. 7,943,656 describes methods for preparing samples of the mono HCl 0.75 hydrate form HO.75-3; one particular example is described below.

[0062] A comparative sample of mono HCl 0.75 hydrate form HO.75-3 can be made, for example, by a process which includes the steps of:

(a) heating the mono HCl dihydrate form H2-1 at a temperature from about 25 to about 55 °C for about 1 to about 2 hours; and

(b) recovering crystals of the mono HCl 0.75 hydrate form HO.75-3.

[0063] A powder x-ray diffraction pattern for mono HCl 0.75 hydrate form HO.75-3 is provided as FIG. 3. The saxagliptin mono HCl 0.75 hydrate form HO.75-3 can be characterized, for example, by powder X-ray diffraction pattern characteristic peak positions comprising the following 2Θ values (CuKa λ - 1.5418 A) 5.0 ± 0.1, 7.0 ± 0.1, 8.1 ± 0.1, 11.4 ± 0.1, 13.4 ± 0.1, 14.0 ± 0.1, 14.5 ± 0.1, 18.6 ± 0.1, 19.4 ± 0.1 and 20.0 ± 0.1 at about room temperature. Alternatively or additionally, the saxagliptin mono HCl 0.75 hydrate form HO.75-3 can be characterized by unit cell parameters substantially equal to the following:

Cell dimensions for single crystal HCl salt (form HO.75-3)

a = 43.913 A

b = 6.759(1) A

c = 17.948 A

a = 90°

β = 134.98(1)°

γ = 90°

Space group C2

Molecules/asymmetric unit 2

wherein said crystalline form is at about ±22°C.

Alternatively or additionally, the mono HCl 0.75 hydrate form H0.75-3 can be characterized by a powder x-ray diffraction pattern substantially equal to that in FIG. 3. Alternatively or additionally, the mono HCl 0.75 hydrate form HO.75-3 can be characterized as described in U.S. Patent no. 7,943,656.

[0064] In another embodiment, the second crystalline HCl salt form is the mono HCl dihydrate form H2-1. For example, when the first crystalline HCl salt form is the H2-1 form, when the particulate pharmaceutical composition is dried only to an intermediate stage of dryness, the mono HCl dihydrate form H2-1 remains.

Otherwise, a particulate pharmaceutical composition comprising, for example, the mono HCl 0.75 hydrate form HO.75-3, can be stored under hydrating conditions to convert the mono HCl 0.75 hydrate form HO.75-3 to the mono HCl dihydrate form H2-1 in situ.

[0065] In another embodiment, the second crystalline HCl salt form is the saxagliptin hydrochloride salt form P-4. A comparative sample of form P-4 can be made, for example, by dissolving the mono HCl dihydrate form H2-1 described in U.S. Patent no. 7,943,656 in aqueous ethanol, then adding ethyl acetate to induce crystallization. A powder x-ray diffraction pattern for the P-4 form is provided as the lower trace in FIG. 16. The saxagliptin HCl salt form P-4 can be characterized, for example, by powder X-ray diffraction pattern characteristic peak positions comprising the following 2Θ values (CuKa λ - 1.5418 A) 7.1 ± 0.1, 8.6 ± 0.1, 9.3 ± 0.1, 10.6 ± 0.1, 12.0 + 0.1, 14.2 + 0.1, 15.3 + 0.1, 16.6 + 0.1, 17.4 + 0.1, 18.6 + 0.1, 19.2 + 0.1, 20.7 + 0.1 and 21.5 + 0.1 at about room temperature.

[0066] In certain embodiments, the second crystalline saxagliptin salt form is a single salt form, for example, one of those described above or elsewhere herein. In certain such embodiments, the second crystalline salt form includes substantially only a single crystalline form, for example, one of those described above or elsewhere herein.

[0067] In other embodiments, the second crystalline salt form is a mixture of crystalline forms. For example, in certain embodiments, the second crystalline salt form is a mixture of the Q-1 form and the mono HCl 0.75 hydrate form HO.75-3. A powder X-ray diffraction pattern of form Q-1 is provided as the middle trace in FIG. 18. A comparative sample of the Q-lform can be made by heating the material made as described above with respect to FIG. 4 at 90 °C. The saxagliptin HCl salt form Q-1 can be characterized, for example, by powder X-ray diffraction pattern characteristic peak positions comprising the following 2Θ values (CuKa λ - 1.5418 A) 7.2 + 0.1, 8.1 ± 0.1, 11.4 + 0.1, 13.6 + 0.1, 14.3 + 0.1, 14.6 + 0.1, 15.8 + 0.1, 16.3 + 0.1, 17.1 + 0.1, 18.5 + 0.1, 19.6 + 0.1, 20.6 + 0.1 and 21.4 + 0.1 at about room temperature. In another embodiment, the second crystalline salt form is a mixture of the mono HC1 dihydrate form H2-1 and the mono HC1 0.75 hydrate form HO.75-3.

[0068] Of course, the person of ordinary skill in the art will appreciate that the first crystalline form and/or the second crystalline form can be different than the ones specifically described herein. In certain embodiments, at least about 70%, at least about 90%, or even at least about 98% of saxagliptin in the particulate pharmaceutical compositions described herein is in a crystalline form. For example, in one embodiment, include at least about 70%, at least about 90%, or even at least about 98%) of saxagliptin in a particulate pharmaceutical composition described herein is the mono HC1 dihydrate H2-1 form of saxagliptin, the mono HC1 0.75 hydrate form HO.75-3 of saxagliptin, or a combination thereof. In one embodiment, include at least about 70%), at least about 90%, or even at least about 98% of saxagliptin in a particulate pharmaceutical composition described herein is the mono HC1 dihydrate H2-1 form of saxagliptin. In another embodiment, include at least about 70%, at least about 90%), or even at least about 98% of saxagliptin in a particulate pharmaceutical composition described herein is the mono HC1 0.75 hydrate form HO.75-3 of saxagliptin. In still other embodiments, at least about 70%, at least about 90%, or even at least about 98% of saxagliptin in a particulate pharmaceutical composition described herein is the P-4 form of saxagliptin. In other embodiments, at least about 70%), at least about 90%, or even at least about 98% of saxagliptin in a particulate pharmaceutical composition described herein is a mixture of the Q-l form of saxagliptin and the mono HC1 0.75 hydrate form HO.75-3 of saxagliptin.

[0069] A variety of polymers can be used to form the particulate pharmaceutical compositions described herein. As the person of ordinary skill in the art will appreciate, the polymer should be one that is soluble in a solvent in which the saxagliptin is substantially insoluble (i.e., in free base and salt form), and which can be precipitated by addition of an antisolvent while maintaining substantial insolubility of the saxagliptin. For example, in certain embodiments, one or more of the polymers (e.g., each of the one or more polymers) is selected from the group consisting of cellulose (e.g., microcrystalline cellulose), starch (e.g., pregelatinized starch, corn starch), hydroxypropylmethyl cellulose, hydroxypropyl cellulose, cellulose acetate, ethyl cellulose, methyl cellulose, sodium carboxymethylcellulose, poly(vinyl pyrrolidone), poly(vinyl pyrrolidone-co-vinyl acetate) (i.e., copovidone). The person of ordinary skill in the art will select other suitable polymers for use in other embodiments of the invention as described herein. In certain embodiments, the one or more polymers include poly(vinyl pyrrolidone-co-vinyl acetate). In one particular embodiment, the one or more polymers consist essentially of poly(vinyl pyrrolidone- co-vinyl acetate). In certain embodiments, the poly(vinyl pyrrolidone-co-vinyl acetate) includes vinyl pyrrolidone in the range of about 30 wt% to about 85 wt% and vinyl acetate in the range of about 15 wt% to about 70 wt%. For example, in one embodiment, the poly(vinyl pyrrolidone-co-vinyl acetate) includes vinyl pyrrolidone in the range of about 50 wt% to about 70 wt% and vinyl acetate in the range of about 30 wt% to about 50 wt%. One example of a suitable poly(vinyl pyrrolidone-co-vinyl acetate) material has about 60 wt% vinyl pyrrolidone and about 40 wt% vinyl acetate (Kollidon® VA 64, BASF). Plasdone™ S-630 copovidone (Ashland) is another example of a suitable poly(vinyl pyrrolidone-co-vinyl acetate) material for use in certain embodiments of the invention.

[0070] The one or more polymers can be provided in any desirable amount, depending, for example, on the ultimate use to which the particulate pharmaceutical composition will be put. For example, in one embodiment, the one or more polymers are provided at a total amount that is at least about 10%, at least about 20%, at least about 30%), or even at least about 40% of the amount of the saxagliptin in the free base form in which it is provided. In certain such embodiments, the one or more polymers are provided at a total amount that is no more than about 1000%), no more than about 700%, no more than about 500%, or even no more than about 200%) of the amount of the saxagliptin in the free base form in which it is provided. For example, the one or more polymers can be provided in an amount in the range of about 10%> to about 1000%), in the range of about 20% to about 700%, or even in the range of about 30%) to about 200%) of the saxagliptin in the free base form in which it is provided.

[0071] A variety of solvents can be used in practicing the methods described herein. As used herein, a "solvent" is a single phase liquid that substantially dissolves the polymer. A solvent can be made of a single component (e.g., ethanol), or of multiple components (e.g., a mixture of isopropanol and water), provided the multiple components together form a single phase mixture. For example, in certain embodiments the solvent includes one or more components selected from the group consisting of methanol, ethanol, isopropanol, water, acetone, methyl ethyl ketone, methyl tert-butyl ether, tetrahydrofuran and aliphatic hydrocarbons. For example, in one embodiment, the solvent for the one or more polymers comprises one or more of methanol, ethanol, isopropanol, n-propanol, acetone, methyl ethyl ketone, optionally in combination with water, and optionally in combination with methyl t-butyl ether, tetrahydrofuran or an aliphatic hydrocarbon. In one particular embodiment, the solvent is a mixture of isopropanol, water, and methyl tert-butyl ether, in which the isopropanol is present in a range of about 50 vol% to about 85 vol%; the water is present in a range of about 3 vol% to about 15 vol%, and the methyl tert-butyl ether is present in an amount in the range of about 20 vol% to about 45 vol%. As the person of ordinary skill in the art will appreciate, the identities and the amounts of the solvent components can be tuned to provide the desired solubility capabilities.

[0072] The person of ordinary skill in the art can select suitable amounts of solvent based on the particular solvent, antisolvent, polymer(s) and saxagliptin used. For example, the solvent can be provided in an amount in the range of about 1 to about 100 Vol, in which Vol is defined as mL solvent per gram of amine

pharmaceutical ingredient (e.g., saxagliptin) in the free base form in which it is provided. In certain embodiments, the solvent is provided in an amount in the range of about 5 Vol to about 50 Vol, or even in the range of about 7 Vol to about 30 Vol.

[0073] Similarly, the amount of antisolvent can be selected based on the particular antisolvent, solvent, polymer(s) and saxagliptin used. For example the solvent can be provided in an amount in the range of about 1 to about 100 Vol, in which Vol is defined as mL antisolvent per gram of amine pharmaceutical ingredient in the free base form in which it is provided. In certain embodiments, the solvent is provided in an amount in the range of about 5 Vol to about 60 Vol, or even in the range of about 7 Vol to about 40 Vol.

[0074] The HC1 can be provided in any convenient form, for example, as concentrated aqueous HC1 (in which case the water forms a component of the solvent), or as gaseous HC1. HC1 can be provided, for example, in an amount of at least about 1, at least about 1.1, or even at least about 1.2 equivalents with respect to the saxagliptin. In certain embodiments, the HC1 is provided in an amount of no more than about 10 equivalents, no more than about 5 equivalents, or even no more than about 2.5 equivalents with respect to the saxagliptin. For example, in certain embodiments, the HCl is present in the solution in an amount in the range of about 1.1 equivalents to about 5 equivalents, or in the range of about 1.2 equivalents to about 2.5 equivalents.

[0075] Notably, in one embodiment, the solvent for the one or more polymers comprises a component that (on its own) is an antisolvent for the one or more polymers, in an amount that does not render the one or more polymers substantially insoluble in the solvent. For example, as described in more detail below, methyl tert- butyl ether can be included in a primarily alcoholic solvent at a relatively low amount, such that the one or more polymers remain soluble therein. Thus, the solubility properties of the solvent can be tuned such that a relatively smaller amount of the antisolvent need be added in order to precipitate the one or more polymers.

[0076] A variety of antisolvents can be used in practicing the methods described herein. As used herein, an "antisolvent" is a liquid in which the one or more polymers are substantially insoluble. The antisolvent is substantially miscible with the solvent, such that they form a single liquid phase when mixed. The antisolvent is selected such that the first crystalline HCl salt form of the saxagliptin is substantially insoluble (e.g., less than about 10 mg/mL, or even less than about 1 mg/mL) in the liquid mixture of solvent and antisolvent. An antisolvent can be made of a single

component (e.g., methyl tert-butyl ether), or of multiple components, provided the multiple components together form a single phase mixture. Of course, the selection of the antisolvent will depend on the identities of the one or more polymers. For example, in certain embodiments), the antisolvent includes one or more components selected from the group consisting of methyl tert-butyl ether, tetrahydrofuran and aliphatic hydrocarbons. For example, in one embodiment, the antisolvent for the one or more polymers includes one or more of methyl t-butyl ether, tetrahydrofuran and aliphatic hydrocarbon.

[0077] In certain embodiments, a method for making a particulate pharmaceutical composition includes providing a solution of the one or more polymers in a solvent, the solution including HCl. The one or more polymers can be, for example, as described above. In one embodiment, the one or more polymers consist essentially of poly(vinyl pyrrolidone-co-vinyl acetate). The solvent can be as described above, for example, methanol, ethanol or isopropanol, optionally in combination with water, optionally in combination with methyl tert-butyl ether (e.g., a mixture of isopropanol, water and methyl tert-butyl ether). The HCl can be provided in any convenient form, for example, as concentrated aqueous HCl (in which case the water forms a component of the solvent), or as gaseous HCl, for example, in the amounts described above. To the solution of the one or more polymers in the solvent is added saxagliptin in a free base form, for example, as a solid. The free base form can be an amorphous form, or can be a crystalline form, and can include water of hydration or other solvate molecules. The saxagliptin in free base form is converted to a crystalline HCl salt form of saxagliptin, in slurry form in the solution of the one or more polymers. To this slurry is added an antisolvent for the one or more polymers, in an amount and under conditions sufficient to precipitate the one or more polymers onto the crystalline saxagliptin HCl salt to form particles as a slurry in the liquid combination of the solvent and the antisolvent. The particles are then recovered from the slurry, for example, as described above.

[0078] In certain embodiments, the slurry of particles is wet milled, for example, substantially simultaneously with the addition of the antisolvent, as described above.

[0079] In certain embodiments, as described above, the solvent is a mixture of isopropanol, water, and methyl tert-butyl ether, in which the isopropanol is present in a range of about 50 vol% to about 85 vol%; the water is present in a range of about 3 vol% to about 15 vol%, and the methyl tert-butyl ether is present in an amount in the range of about 20 vol% to about 45 vol%. Such a solvent can be especially useful when the one or more polymers include (or consist essentially of) poly(vinyl pyrrolidone-co-vinyl acetate). As the person of ordinary skill in the art will appreciate, the identities and the amounts of the solvent components can be tuned to provide the desired solubility capabilities.

[0080] Another aspect of the invention is a particulate pharmaceutical composition including (or consisting essentially of) a plurality of particles, each particle including saxagliptin in a crystalline HCl salt form and one or more polymers Saxagliptin crystalline HCl salt form and one or more polymers can be, for example, as described above with respect to the methods of the disclosure. In certain embodiments, the one or more polymers can include poly(vinyl pyrrolidone-co-vinyl acetate) (also known as copovidone), or even can consist essentially of poly(vinyl pyrrolidone-co-vinyl acetate). In certain embodiments, the crystalline HCl salt is the mono HCl salt of saxagliptin in mono HCl salt 0.75 hydrate form HO.75-3, as described above.

[0081] In certain embodiments of the methods described herein, the one or more polymers are precipitated onto the saxagliptin HCl salt. Accordingly, in certain embodiments of the particulate pharmaceutical formulations described herein, the crystalline HCl salt form of the saxagliptin is substantially coated by the one or more polymers in each particle.

[0082] The average particle size of the particulate pharmaceutical composition can be, for example, less than about 500 μπι, or even less than about 100 μιη. For example, in certain embodiments, the particulate pharmaceutical compositions described herein have a D ₅₀ value in the range of about 1 μιη to about 100 μιη. For example, in certain embodiments, the D ₅₀ value is in the range of about 2 μιη to about 50 μπι, or even in the range of about 3 μιη to about 30 μιη. In certain embodiments, the particulate pharmaceutical compositions described herein have a D ₉₀ value in the range of about 10 μιη to about 300 μιη. For example, in certain embodiments, the D ₉₀ value is in the range of about 20 μιη to about 200 μπι, or even in the range of about 30 μπι to about 150 μιη. The methods described herein can be used to provide particulate pharmaceutical compositions as lump-free, fine particulate powders.

[0083] The particulate pharmaceutical compositions can be formed with a variety of relative amounts of the one or more polymers and the crystalline HCl salt form of saxagliptin. For example, in certain embodiments, the ratio of the one or more polymers to the crystalline HCl salt form of is in the range of about 4: 1 to about 1 :4. In other embodiments, the ratio of the one or more polymers to the crystalline HCl salt form of saxagliptin is in the range of about 3 : 1 to about 1 :3. In other

embodiments, the ratio of the one or more polymers to the crystalline HCl salt form of saxagliptin is in the range of about 1.5: 1 to about 1 :2.5. The particulate

pharmaceutical composition can be composed primarily of the one or more polymers and the crystalline HCl salt form of saxagliptin. For example, in certain

embodiments, at least about 80 wt%, at least about 90 wt%, or even at least about 95 wt% of the particulate pharmaceutical composition is the one or more polymers and the crystalline HCl salt form of saxagliptin. In certain embodiments, the particulate pharmaceutical composition consists essentially of the one or more polymers or the crystalline HCl salt form saxagliptin. [0084] While in some aspects the invention has been described above with respect to HC1 salts of saxagliptin, other aspects of the invention relate to the use of different salts of saxagliptin, e.g., different hydrohalic acid salts such as saxagliptin HBr salts and saxagliptin HI salts. Crystalline salt forms of saxagliptin HBr and saxagliptin HI are described in more detail in U.S. Patent no. 7,943,656. The person of ordinary skill in the art will appreciate that the methods described herein can be adapted by using HI or HBr in place of the HC1 to provide particulate pharmaceutical compositions that include crystalline salt form of a saxagliptin HBr salt or a saxagliptin HI salt.

[0085] The particulate pharmaceutical compositions described herein can be further processed in any number of ways. For example, in one embodiment, the particulate pharmaceutical composition is compressed, alone or together with other excipients and/or additional active pharmaceutical ingredients, to form one or more tablets. Additionally, in one embodiment, the particulate pharmaceutical composition is compressed, alone or together with other excipients, additional active

pharmaceutical ingredients, and a stabilizing agent, for example, alginic acid, to form one or more tablets. Advantageously, the particulate pharmaceutical composition according to certain embodiments of the disclosure can be directly compressed, without the need for intermediate granulation. The one or more tablets can be coated or further processed, as would be apparent to the person of skill in the art.

[0086] For example, in one embodiment, a compressed tablet dosage form comprises (i.e., in a compressed layer) a particulate pharmaceutical composition as described herein; optionally one or more additional excipients; and optionally one or more additional active pharmaceutical ingredients and/or stabilizing agent. The one or more optional additional excipients can be, for example, one or more binders, one or more fillers, one or more disintegrants, one or more glidants and/or anti adherents; and/or one or more lubricants, provided that when the one or more excipients are silicon dioxide based excipients the excipients are present in amount no more than 1.5 wt%, preferably, less than 1.5 wt %. The tablet dosage form can be a single layer tablet; or can have one or more additional layers (i.e., in addition to the layer of the particulate pharmaceutical compositions as described herein).

[0087] Examples of fillers suitable for use in the tablet dosage forms described herein include, but are not limited to, cellulose derivatives, such as microcrystalline cellulose or wood cellulose, lactose, sucrose, starch, pregelatinized starch, dextrose, mannitol, fructose, xylitol, sorbitol, corn starch, modified corn starch, inorganic salts such as calcium carbonate, calcium phosphate, dicalcium phosphate, calcium sulfate, dextrin/dextrates, maltodextrin, compressible sugars, and other known bulking agents or fillers, and/or mixtures of two or more thereof. Several types of microcrystalline cellulose are suitable for use in the formulations described herein, for example, microcrystalline cellulose selected from the group consisting of Avicel® types:

PH101, PH102, PH103, PH105, PH 112, PHI 13, PH200, PH301, and other types of microcrystalline cellulose, such as silicified microcrystalline cellulose. Several types of lactose are suitable for use in the formulations described herein, for example, lactose selected from the group consisting of anhydrous lactose, lactose monohydrate, lactose fast flow, directly compressible anhydrous lactose, and modified lactose monohydrate. In one embodiment of the invention, the filler is a calcium phosphate (e.g., dibasic calcium phosphate anhydrous, available under the trade name A-Tab ^® ).

[0088] Examples of binders suitable for use in the tablet dosage forms described herein include, but are not limited to, hydroxypropyl cellulose, corn starch, pregelatinized starch, modified corn starch, polyvinyl pyrrolidone (PVP) (typical molecular weight ranging from about 5,000 to about 1,000,000, preferably about 40,000 to 50,000), hydroxypropyl methylcellulose (HPMC), lactose, gum acacia, ethyl cellulose, cellulose acetate, as well as a wax binder such as carnauba wax, paraffin, spermaceti, polyethylenes or microcrystalline wax, as well as other conventional binding agents and/or mixtures of two or more thereof.

[0089] Examples of disintegrants suitable for use in the tablet dosage forms described herein include, but are not limited to, croscarmellose sodium, crospovidone, starch, potato starch, pregelatinized starch, corn starch, sodium starch glycolate, microcrystalline cellulose, low substituted hydroxypropyl cellulose and other known disintegrants. Several specific types of disintegrant are suitable for use in the formulations described herein. For example, any grade of crospovidone can be used, including for example crospovidone XL- 10, and includes members selected from the group consisting of Kollidon CL®, Polyplasdone XL®, Kollidon CL-M®,

Polyplasdone XL- 10®, and Polyplasdone INF- 10®. In one embodiment, the disintegrant, if present, is sodium starch glycolate, croscarmellose sodium and/or crospovidone. In one embodiment, the disintegrant is crospovidone. In one specific embodiment, the disintegrant is crospovidone XL- 10 with peroxide levels below 400 parts per million (ppm). These materials are also referred to as insoluble polyvidone, insoluble PVP, crosslinked PVP, and PVPP. The crospovidone can be substituted with croscarmellose sodium, sodium starch glycolate, or pregelatinized starch (at, for example, a 5-10% concentration).

[0090] Examples of lubricants suitable for use herein include, but are not limited to, magnesium stearate, zinc stearate, calcium stearate, talc, carnauba wax, stearic acid, palmitic acid, sodium stearyl fumarate, sodium laurel sulfate, glyceryl palmitostearate, palmitic acid, myristic acid and hydrogenated vegetable oils and fats, as well as other known lubricants, and/or mixtures of two or more thereof. In one embodiment, the lubricant, if present, is magnesium stearate. In another embodiment, the lubricant is sodium stearyl fumarate.

[0091] Examples of glidants and/or anti-adherents suitable for use in the table dosage forms described herein include but are not limited to, silicon dioxide

(generally), colloidal silicon dioxide, magnesium silicate, magnesium trisilicate, talc, and other forms of silicon dioxide, such as aggregated silicates and hydrated silica, provided that when the one or more glidants and/or anti-adherents are a silicon dioxide based glidants and/or anti-adherents the glidants and/or anti -adherents are present in amount no more than 1.5 wt%, preferably, less than 1.5 wt %.

[0092] The tablet dosage forms described herein can be coated, for example using coating materials that are conventional in the art. For example, in one embodiment, the coating material is an Opadry® material (e.g., which contains a mixture of 40% poly(vinyl alcohol), about 20% poly(ethylene glycol), about 15% talc and about 25% titanium dioxide).

[0093] As noted above, in certain embodiments, the dosage forms described herein can include one or more additional active pharmaceutical ingredients. The one or more active pharmaceutical ingredients can be provided, for example, in the same tablet layer as the saxagliptin, or in a different tablet layer. Thus, in certain embodiments, tablets are provided as monolithic tablets, with all active

pharmaceutical ingredients in admixture in a single compressed phase. In other embodiments, tablets are provided as multilayer tablets, with different active pharmaceutical ingredients provided in different layers. [0094] For example, when a dosage form of saxagliptin can further include one or more other types of antidiabetic agents (employed to treat diabetes and related diseases) and/or one or more other types of therapeutic agents.

[0095] The other type of antidiabetic agent which may be optionally employed in combination with the crystalline HC1 salt form of saxagliptin may be 1,2,3 or more antidiabetic agents or antihyperglycemic agents including insulin secretagogues or insulin sensitizers, or other antidiabetic agents preferably having a mechanism of action different from DPP4 inhibition and may include biguanides, sulfonyl ureas, glucosidase inhibitors, PPAR γ agonists, such as thiazolidinediones, SGLT2 inhibitors, PPAR α/γ dual agonists, aP2 inhibitors, glycogen phosphorylase inhibitors, advanced glycosylation end (AGE) products inhibitors, and/or meglitinides, as well as insulin, and/or glucagon-like peptide-1 (GLP-1) or mimetics thereof.

[0096] It is believed that the use of the compounds of structure I in combination with 1, 2, 3 or more other antidiabetic agents produces antihyperglycemic results greater than that possible from each of these medicaments alone and greater than the combined additive anti -hyperglycemic effects produced by these medicaments.

[0097] The other antidiabetic agent may be an oral antihyperglycemic agent preferably a biguanide such as metformin or phenformin or salts thereof, preferably metformin HC1.

[0098] Where the other antidiabetic agent is a biguanide, saxagliptin can be employed in a weight ratio to biguanide, for example, within the range from about 0.01 : 1 to about 100: 1, preferably from about 0.1 : 1 to about 5: 1.

[0099] The other antidiabetic agent may also preferably be a sulfonyl urea such as glyburide (also known as glibenclamide), glimepiride (disclosed in U.S. Patent No. 4,379,785), glipizide, gliclazide or chlorpropamide, other known sulfonylureas or other antihyperglycemic agents which act on the ATP-dependent channel of the β- cells, with glyburide and glipizide being preferred, which may be administered in the same or in separate oral dosage forms.

[00100] Saxagliptin can be employed in a weight ratio to the sulfonyl urea, for example, in the range from about 0.01 : 1 to about 100:1, preferably from about 0.05:1 to about 5:1.

[00101] The oral antidiabetic agent may also be a glucosidase inhibitor such as acarbose (disclosed in U.S. Patent No. 4,904,769) or miglitol (disclosed in U.S. Patent No. 4,639,436), which may be administered in the same or in a separate oral dosage forms.

[00102] Saxagliptin can be employed in a weight ratio to the glucosidase inhibitor, for example, within the range from about 0.01 : 1 to about 100: 1, preferably from about 0.2: 1 to about 50: 1.

[00103] Saxagliptin may be employed in combination with a PPAR γ agonist such as a thiazolidinedione oral anti -diabetic agent or other insulin sensitizers (which has an insulin sensitivity effect in NIDDM patients) such as troglitazone (Warner- Lambert's Rezulin®, disclosed in U.S. Patent No. 4,572,912), rosiglitazone (SKB), pioglitazone (Takeda), Mitsubishi's MCC-555 (disclosed in U.S. Patent No.

5,594,016), Glaxo-Wellcome's GL-262570, englitazone (CP-68722, Pfizer) or darglitazone (CP-86325, Pfizer, isaglitazone (MIT/J&J), JTT-501 (JPNT/P&U), L- 895645 (Merck), R-l 19702 (Sankyo/WL), NN-2344 (Dr. Reddy/NN), or YM-440 (Yamanouchi), preferably rosiglitazone and pioglitazone.

[00104] Saxagliptin can be employed in a weight ratio to the thiazolidinedione, for example, in an amount within the range from about 0.01 : 1 to about 100: 1, preferably from about 0.1 : 1 to about 10: 1.

[00105] In certain embodiments, the sulfonyl urea and thiazolidinedione in amounts of less than about 150 mg oral antidiabetic agent can be incorporated in a single tablet with the saxagliptin.

[00106] Saxagliptin may also be employed in combination with a

antihyperglycemic agent such as insulin or with glucagon-like peptide-1 (GLP-1) such as GLP-1Q-36) amide, GLP-l(7-36) amide, GLP-1 (7-37) (as disclosed in U.S. Patent No. 5,614,492 to Habener, disclosure of which is incorporated herein by reference), or a GLP-1 mimic such as AC2993 or Exendin-4 (Amylin) and LY-315902 or LY- 307167 (Lilly) and NN2211 (Novo-Nordisk), which may be administered via injection, intranasal, or by transdermal or buccal devices.

[00107] Where present, metformin, the sulfonyl ureas, such as glyburide, glimepiride, glipyride, glipizide, chlorpropamide and gliclazide and the glucosidase inhibitors acarbose or miglitol or insulin (injectable, pulmonary, buccal, or oral) may be employed in formulations as described above and in amounts and dosing as indicated in the Physician's Desk Reference (PDR). [00108] Where present, metformin or salt thereof may be employed in amounts within the range from about 500 to about 2000 mg per day which may be

administered in single or divided doses one to four times daily.

[00109] Where present, the thiazolidinedione anti-diabetic agent may be employed in amounts within the range from about 0.01 to about 2000 mg/day which may be administered in single or divided doses one to four times per day.

[00110] Where present insulin may be employed in formulations, amounts and dosing as indicated by the Physician's Desk Reference.

[00111] Where present GLP-1 peptides may be administered in oral buccal formulations, by nasal administration (for example inhalation spray) or parenterally as described in U.S. Patent Nos. 5,346,701 (TheraTech), 5,614,492 and 5,631,224 which are incorporated herein by reference.

[00112] The other antidiabetic agent may also be a PPAR α/γ dual agonist such as AR-H039242 (Astra/Zeneca), GW-409544 (Glaxo-Wellcome), KRP297 (Kyorin Merck) as well as those disclosed by Murakami et al, "A Novel Insulin Sensitizer Acts As a Coligand for Peroxisome Proliferation - Activated Receptor Alpha (PPAR alpha) and PPAR gamma. Effect on PPAR alpha Activation on Abnormal Lipid Metabolism in Liver of Zucker Fatty Rats", Diabetes 47, 1841-1847 (1998), and in U.S. application Serial No. 09/664,598, filed September 18, 2000, (attorney file LA29NP) the disclosure of which is incorporated herein by reference, employing dosages as set out therein, which compounds designated as preferred are preferred for use herein.

[00113] The other antidiabetic agent may be an SGLT2 inhibitor such as disclosed in U.S. Patents Nos. 6,414, 126 and 6,515, 117, each of which is incorporated herein by reference. In certain embodiments, the SGLT2 inhibitor is dapagliflozin, the SGLT2 inhibitor compound described in U.S. Patent no. 6,515,117. The dapagliflozin can be used at a dosage, for example, in the range of about 0.5 mg to about 100 mg (e.g., 1 mg, 2.5 mg, 5 mg, 10 mg, 25 mg, 50 mg, 100 mg).

[00114] The other antidiabetic agents may be an SGLT2 inhibitor such as disclosed in U.S. Patents Nos. 6,414,126 and 6,515,117, each of which is incorporated herein by reference, and a biguanide such as metformin or phenformin or salts thereof, preferably metformin HC1. In certain embodiments, the SGLT2 inhibitor is dapagliflozin, the SGLT2 inhibitor compound described in U.S. Patent no. 6,515, 117, and the biguanide is metformin or salts thereof, preferably metformin HC1. The dapagliflozin can be used at a dosage, for example, in the range of about 0.5 mg to about 100 mg (e.g., 1 mg, 2.5 mg, 5 mg, 10 mg, 25 mg, 50 mg, 100 mg).

[00115] The other antidiabetic agent which may be optionally employed in combination with the saxagliptin may be an aP2 inhibitor such as disclosed in U.S. Patents nos. 7,390,824 and 6,927,227, each of which is incorporated herein by reference, employing dosages as set out herein. Preferred are the compounds designated as preferred in the above application.

[00116] The other antidiabetic agent which may be optionally employed in combination with the saxagliptin may be a glycogen phosphorylase inhibitor such as disclosed in WO 96/39384, WO 96/39385, EP 978279, WO 2000/47206, WO 99/43663, and U.S. Patent Nos. 5,952,322 and 5,998,463, WO 99/26659 and EP 1041068.

[00117] The meglitinide which may optionally be employed in combination with the saxagliptin may be repaglinide, nateglinide (Novartis) or KAD1229 (PF/Kissei), with repaglinide being preferred.

[00118] The saxagliptin can be employed in a weight ratio to the meglitinide, PPAR a agonist, PPAR α/γ dual agonist, SGLT2 inhibitor, aP2 inhibitor, or glycogen phosphorylase inhibitor, for example, within the range from about 0.01 : 1 to about 100: 1, preferably from about 0.1 : 1 to about 10: 1.

[00119] The hypolipidemic agent or lipid-modulating agent which may be optionally employed in combination with the saxagliptin may include 1,2,3 or more MTP inhibitors, HMG CoA reductase inhibitors, squalene synthetase inhibitors, fibric acid derivatives, ACAT inhibitors, lipoxygenase inhibitors, cholesterol absorption inhibitors, ileal Na+/bile acid cotransporter inhibitors, upregulators of LDL receptor activity, ATP citrate lyase inhibitors, cholesteryl ester transfer protein inhibitors, bile acid sequestrants, and/or nicotinic acid and derivatives thereof.

[00120] MTP inhibitors include MTP inhibitors disclosed in U.S. Patent No.

5,595,872, U.S. Patent No. 5,739,135, U.S. Patent No. 5,712,279, U.S. Patent No. 5,760,246, U.S. Patent No. 5,827,875, U.S. Patent No. 5,885,983 and U.S. Patent No. 5,962,440, as well as implitapide (Bayer). Preferred are each of the preferred MTP inhibitors disclosed in each of the above patents and applications. [00121] A preferred MTP inhibitor is 9-[4-[4-[[2-(2,2,2-

Trifluoroethoxy)benzoyl]amino]-l-piperidinyl]butyl]-N-(2, 2,2-trifluoroethyl)-9H- fluorene-9-carboxamide:

[00122] The hypolipidemic agent may be an HMG CoA reductase inhibitor which includes, but is not limited to, mevastatin and related compounds as disclosed in U.S. Patent No. 3,983, 140, lovastatin (mevinolin) and related compounds as disclosed in U.S. Patent No. 4,231,938, pravastatin and related compounds such as disclosed in U.S. Patent No. 4,346,227, simvastatin and related compounds as disclosed in U.S. Patent Nos. 4,448,784 and 4,450,171. Other HMG CoA reductase inhibitors which may be employed herein include, but are not limited to, fluvastatin, disclosed in U.S. Patent No. 5,354,772, cerivastatin disclosed in U.S. Patent Nos. 5,006,530 and 5, 177,080, atorvastatin disclosed in U.S. Patent Nos. 4,681,893, 5,273,995, 5,385,929 and 5,686, 104, atavastatin (Nissan/Sankyo's nisvastatin (NK-104)) disclosed in U.S. Patent No. 5,011,930, Shionogi-Astra/Zeneca visastatin (ZD-4522) disclosed in U.S. Patent No. 5,260,440, and rosuvastatin.

[00123] The squalene synthetase inhibitors suitable for use in the dosage forms described herein include, but are not limited to, a-phosphono-sulfonates disclosed in U.S. Patent No. 5,712,396, those disclosed by Biller et al, J. Med. Chem., 1988, Vol. 31, No. 10, pp 1869-1871, including isoprenoid (phosphinyl-methyl)phosphonates as well as other known squalene synthetase inhibitors, for example, as disclosed in U.S. Patent No. 4,871,721 and 4,924,024 and in Biller, S.A., Neuenschwander, K., Ponpipom, M.M., and Poulter, CD., Current Pharmaceutical Design, 2, 1-40 (1996).

[00124] In addition, other squalene synthetase inhibitors suitable for use in the dosage forms described herein include the terpenoid pyrophosphates disclosed by P. Ortiz de Montellano et al, J. Med. Chem., 1977, 20, 243-249, the farnesyl diphosphate analog A and presqualene pyrophosphate (PSQ-PP) analogs as disclosed by Corey and Volante, J. Am. Chem. Soc, 1976, 98, 1291-1293, phosphinylphosphonates reported by McClard, R.W. et al, J.A.C.S., 1987, 109, 5544 and cyclopropanes reported by Capson, T.L., PhD dissertation, June, 1987, Dept. Med. Chem. U of Utah, Abstract, Table of Contents, pp 16, 17, 40-43, 48-51, Summary.

[00125] Other hypolipidemic agents suitable for use in the dosage forms described herein include, but are not limited to, fibric acid derivatives, such as fenofibrate, gemfibrozil, clofibrate, bezafibrate, ciprofibrate, clinofibrate and the like, probucol, and related compounds as disclosed in U.S. Patent No. 3,674,836, probucol and gemfibrozil being preferred, bile acid sequestrants such as cholestyramine, colestipol and DEAE-Sephadex (Secholex®, Policexide®), as well as lipostabil (Rhone- Poulenc), Eisai E-5050 (an N-substituted ethanolamine derivative), imanixil (HOE- 402), tetrahydrolipstatin (THL), istigmastanylphos-phorylcholine (SPC, Roche), aminocyclodextrin (Tanabe Seiyoku), Ajinomoto AJ-814 (azulene derivative), melinamide (Sumitomo), Sandoz 58-035, American Cyanamid CL-277,082 and CL- 283,546 (di substituted urea derivatives), nicotinic acid, acipimox, acifran, neomycin, p-aminosalicylic acid, aspirin, poly(diallylmethylamine) derivatives such as disclosed in U.S. Patent No. 4,759,923, quaternary amine poly(diallyldimethylammonium chloride) and ionenes such as disclosed in U.S. Patent No. 4,027,009, and other known serum cholesterol lowering agents.

[00126] The other hypolipidemic agent may be an ACAT inhibitor such as disclosed in, Drugs of the Future 24, 9-15 (1999), (Avasimibe); "The ACAT inhibitor, Cl-1011 is effective in the prevention and regression of aortic fatty streak area in hamsters", Nicolosi et al, Atherosclerosis (Shannon, Irel). (1998), 137(1), 77- 85; "The pharmacological profile of FCE 27677: a novel ACAT inhibitor with potent hypolipidemic activity mediated by selective suppression of the hepatic secretion of ApoBlOO-containing lipoprotein", Ghiselli, Giancarlo, Cardiovasc. Drug Rev.

(1998), 16(1), 16-30; "RP 73163 : a bioavailable alkylsulfinyl-diphenylimidazole ACAT inhibitor", Smith, C, et al, Bioorg. Med. Chem. Lett. (1996), 6(1), 47-50; "ACAT inhibitors: physiologic mechanisms for hypolipidemic and anti- atherosclerotic activities in experimental animals", Krause et al, Editor(s): Ruffolo, Robert R., Jr.; Hollinger, Mannfred A., Inflammation: Mediators Pathways (1995), 173-98, Publisher: CRC, Boca Raton, Fla.; "ACAT inhibitors: potential anti- atherosclerotic agents", Sliskovic et al, Curr. Med. Chem. (1994), 1(3), 204-25; "Inhibitors of acyl-CoA: cholesterol O-acyl transferase (AC AT) as hypocholesterolemic agents. 6. The first water-soluble ACAT inhibitor with lipid- regulating activity. Inhibitors of acyl-CoA:cholesterol acyltransferase (ACAT). 7. Development of a series of substituted N-phenyl-N'-[(l- phenylcyclopentyl)methyl]ureas with enhanced hypocholesterolemic activity", Stout et al, Chemtracts: Org. Chem. (1995), 8(6), 359-62, or TS-962 (Taisho

Pharmaceutical Co. Ltd).

[00127] The hypolipidemic agent may be an upregulator of LD2 receptor activity such as MD-700 (Taisho Pharmaceutical Co. Ltd) and LY295427 (Eli Lilly).

[00128] The hypolipidemic agent may be a cholesterol absorption inhibitor preferably Schering-Plough' s SCH48461 as well as those disclosed in Atherosclerosis 115, 45-63 (1995) and J. Med. Chem. 41, 973 (1998).

[00129] The hypolipidemic agent may be an ileal NaVbile acid cotransporter inhibitor such as disclosed in Drugs of the Future, 24, 425-430 (1999).

[00130] The lipid-modulating agent may be a cholesteryl ester transfer protein (CETP) inhibitor such as Pfizer' s CP 529,414 (WO/0038722 and EP 818448) and Pharmacia's SC-744 and SC-795.

[00131] The ATP citrate lyase inhibitor which may be employed in the

combination of the invention may include, for example, those disclosed in U.S. Patent No. 5,447,954.

[00132] Preferred hypolipidemic agents are pravastatin, lovastatin, simvastatin, atorvastatin, rosuvastatin, fluvastatin, cerivastatin, atavastatin and ZD-4522.

[00133] The above-mentioned U.S. patents are incorporated herein by reference. The amounts and dosages employed will be as indicated in the Physician's Desk Reference and/or in the patents set out above.

[00134] Saxagliptin can be employed in a weight ratio to the hypolipidemic agent, for example, within the range from about 500: 1 to about 1 :500, preferably from about 100: 1 to about 1 : 100.

[00135] In certain embodiments, the dosage forms described herein can include one or more stabilizing agents, for example, alginic acid.

[00136] The dose administered must be carefully adjusted according to age, weight and condition of the patient, as well as the route of administration, dosage form and regimen and the desired result. [00137] The dosages and formulations for the hypolipidemic agent will be as disclosed in the various patents and applications discussed above.

[00138] The dosages and formulations for the other hypolipidemic agent to be employed, where applicable, will be as set out in the latest edition of the Physicians' Desk Reference.

[00139] For oral administration, a satisfactory result may be obtained employing the MTP inhibitor in an amount within the range of from about 0.01 mg/kg to about 500 mg and preferably from about 0.1 mg to about 100 mg, one to four times daily.

[00140] A preferred oral dosage form, such as tablets or capsules, will contain the MTP inhibitor in an amount of from about 1 to about 500 mg, preferably from about 2 to about 400 mg, and more preferably from about 5 to about 250 mg, one to four times daily.

[00141] For oral administration, a satisfactory result may be obtained employing an FDVIG CoA reductase inhibitor, for example, pravastatin, lovastatin, simvastatin, atorvastatin, rosuvastatin, fluvastatin or cerivastatin in dosages employed as indicated in the Physician's Desk Reference, such as in an amount within the range of from about 1 to 2000 mg, and preferably from about 4 to about 200 mg.

[00142] The squalene synthetase inhibitor may be employed in dosages in an amount within the range of from about 10 mg to about 2000 mg and preferably from about 25 mg to about 200 mg.

[00143] A preferred oral dosage form, such as tablets or capsules, will contain the FDVIG CoA reductase inhibitor in an amount from about 0.1 to about 100 mg, preferably from about 5 to about 80 mg, and more preferably from about 10 to about 40 mg.

[00144] A preferred oral dosage form, such as tablets or capsules will contain the squalene synthetase inhibitor in an amount of from about 10 to about 500 mg, preferably from about 25 to about 200 mg.

[00145] The other hypolipidemic agent may also be a lipoxygenase inhibitor including a 15 -lipoxygenase (15-LO) inhibitor such as benzimidazole derivatives as disclosed in WO 97/12615, 15-LO inhibitors as disclosed in WO 97/12613, isothiazolones as disclosed in WO 96/38144, and 15-LO inhibitors as disclosed by Sendobry et al "Attenuation of diet-induced atherosclerosis in rabbits with a highly selective 15-lipoxygenase inhibitor lacking significant antioxidant properties", Brit. J. Pharmacology (1997) 120, 1199-1206, and Cornicelli et al, " 15 -Lipoxygenase and its Inhibition: A Novel Therapeutic Target for Vascular Disease", Current

Pharmaceutical Design, 1999, 5, 11-20.

[00146] The compositions described above may be administered in the dosage forms as described above in single or divided doses of one to four times daily. It may be advisable to start a patient on a low dose combination and work up gradually to a high dose combination.

[00147] The preferred hypolipidemic agent is pravastatin, simvastatin, lovastatin, atorvastatin, rosuvastatin, fluvastatin or cerivastatin.

[00148] The other type of therapeutic agent which may be optionally employed with saxagliptin may be 1, 2, 3 or more of an anti-obesity agent including a beta 3 adrenergic agonist, a lipase inhibitor, a serotonin (and dopamine) reuptake inhibitor, a thyroid receptor beta drug, an anorectic agent and/or a fatty acid oxidation

upregulator.

[00149] The beta 3 adrenergic agonist which may be optionally employed in combination with saxagliptin may be AJ9677 (Takeda/Dainippon), L750355 (Merck), or CP331648 (Pfizer) or other known beta 3 agonists as disclosed in U.S. Patent Nos. 5,541,204, 5,770,615, 5,491,134, 5,776,983 and 5,488,064, with AJ9677, L750,355 and CP331648 being preferred.

[00150] The lipase inhibitor which may be optionally employed in combination with saxagliptin may be orlistat or ATL-962 (Alizyme), with orlistat being preferred.

[00151] The serotonin (and dopoamine) reuptake inhibitor which may be optionally employed in combination with saxagliptin may be sibutramine, topiramate (Johnson & Johnson) or axokine (Regeneron), with sibutramine and topiramate being preferred.

[00152] The thyroid receptor beta compound which may be optionally employed in combination with saxagliptin may be a thyroid receptor ligand as disclosed in

W097/21993 (U. Cal SF), WO99/00353 (KaroBio) and GB98/284425 (KaroBio), with compounds of the KaroBio applications being preferred.

[00153] The anorectic agent which may be optionally employed in combination with saxagliptin may be dexamphetamine, phentermine, phenylpropanolamine or mazindol, with dexamphetamine being preferred. [00154] The fatty acid oxidation upregulator which may be optionally employed in combination with saxagliptin can be famoxin (Genset).

[00155] The various anti-obesity agents described above may be employed in dosages and regimens as generally known in the art or in the PDR.

[00156] The infertility agent which may be optionally employed in combination with saxagliptin may be 1, 2, or more of clomiphene citrate (Clomid®, Aventis), bromocriptine mesylate (Parlodel®, Novartis),LHRH analogs, Lupron (TAP Pharm.), danazol, Danocrine (Sanofi), progestogens or glucocorticoids, which may be employed in amounts specified in the PDR.

[00157] The agent for polycystic ovary syndrome which may be optionally employed in combination with saxagliptin may be 1, 2, or more of gonadotropin releasing hormone (GnRH), leuprolide (Lupron®), Clomid®, Parlodel®, oral contraceptives or insulin sensitizers such as PPAR agonists, or other conventional agents for such use which may be employed in amounts specified in the PDR.

[00158] The agent for treating growth disorders and/or frailty which may be optionally employed in combination with saxagliptin may be 1, 2, or more of a growth hormone or growth hormone secretagogue such as MK-677 (Merck), CP-424,391 (Pfizer), and compounds disclosed in U.S. Serial No. 09/506,749 filed February 18, 2000 (attorney docket LA26), as well as selective androgen receptor modulators (SARMs), which is incorporated herein by reference, which may be employed in amounts specified in the PDR, where applicable.

[00159] The agent for treating arthritis which may be optionally employed in combination with saxagliptin may be 1, 2, or more of aspirin, indomethacin, ibuprofen, diclofenac sodium, naproxen, nabumetone (Relafen®, SmithKline Beecham), tolmetin sodium (Tolectin®, Ortho-McNeil), piroxicam (Feldene®, Pfizer), ketorolac tromethamine (Toradol®, Roche), celecoxib (Celebrex®, Searle), rofecoxib (Vioxx®, Merck) and the like, which may be employed in amounts specified in the PDR.

[00160] Conventional agents for preventing allograft rejection in transplantation such as cyclosporin, Sandimmune (Novartis), azathioprine, Immuran (Faro) or methotrexate may be optionally employed in combination with the DPP4 inhibitor of the invention, which may be employed in amounts specified in the PDR. [00161] Conventional agents for treating autoimmune diseases such as multiple sclerosis and immunomodulatory diseases such as lupus erythematosis, psoriasis, for example, azathioprine, Immuran, cyclophosphamide, NSAIDS such as ibuprofen, cox 2 inhibitors such as Vioxx and Celebrex, glucocorticoids and hydroxychloroquine, may be optionally employed in combination with the DP4 inhibitor of the invention, which may be employed in amounts specified in the PDR.

[00162] The AIDS agent which may be optionally employed in combination with saxagliptin may be a non-nucleoside reverse transcriptase inhibitor, a nucleoside reverse transcriptase inhibitor, a protease inhibitor and/or an AIDS adjunct anti- infective and may be 1, 2, or more of dronabinol (Marinol®, Roxane Labs), didanosine (Videx®, Bristol-Myers Squibb), megestrol acetate (Megace®, Bristol- Myers Squibb), stavudine (Zerit®, Bristol-Myers Squibb), delavirdine mesylate (Rescriptor®, Pharmacia), lamivudine/zidovudine (Combivir™, Glaxo), lamivudine (Epivir™, Glaxo), zalcitabine (Hivid®, Roche), zidovudine (Retrovir®, Glaxo), indinavir sulfate (Crixivan®, Merck), saquinavir (Fortovase™, Roche), saquinovir mesylate (Invirase®, Roche), ritonavir (Norvir®, Abbott), nelfinavir (Viracept®, Agouron).

[00163] The above anti-AIDS agents may be employed in amounts specified in the PDR.

[00164] The agent for treating inflammatory bowel disease or syndrome which may be optionally employed in combination with saxagliptin may be 1, 2, or more of sulfasalazine, salicylates, mesalamine (Asacol®, P&G) or Zelmac®, (Bristol-Myers Squibb), which may be employed in amounts specified in the PDR or otherwise known in the art.

[00165] The agent for treating osteoporosis which may be optionally employed in combination with saxagliptin may be 1, 2, or more of alendronate sodium

(Fosamax®, Merck, tiludronate (Skelid®, Sanofi), etidronate disodium (Didronel®, P&G), raloxifene HC1 (Evista®, Lilly), which may be employed in amounts specified in the PDR.

[00166] Accordingly, in certain embodiments, a dosage form as described herein (e.g., a tablet dosage form) further includes an antidiabetic agent other than a DP4 inhibitor for treating diabetes and related diseases, an anti-obesity agent and/or a lipid-modulating agent. The antidiabetic agent, the anti-obesity agent and/or the lipid modulating agent can be provided, for example, in the same tablet layer as the saxagliptin HCl, or in a separate tablet layer (e.g., as the second layer in a bilayer tablet).

[00167] For example, in one embodiment, a dosage form as described herein further includes an antidiabetic agent other than a DPP4 inhibitor. The antidiabetic agent can be provided, for example, in the same tablet layer as the saxagliptin HCl, or in a separate tablet layer (e.g., as the second layer in a bilayer tablet). In certain embodiments, the antidiabetic agent is 1, 2, 3 or more of a biguanide, a sulfonyl urea, a glucosidase inhibitor, a PPAR γ agonist, a PPAR α/γ dual agonist, an SGLT2 inhibitor, an aP2 inhibitor, a glycogen phosphorylase inhibitor, an AGE inhibitor, an insulin sensitizer, a glucagon-like peptide- 1 (GLP-1) or mimetic thereof, insulin and/or a meglitinide. In certain embodiments, the antidiabetic agent is 1, 2, 3 or more of metformin, glyburide, glimepiride, glipyride, glipizide, chlorpropamide, gliclazide, acarbose, miglitol, pioglitazone, troglitazone, rosiglitazone, insulin, Gl -262570, isaglitazone, JTT-501, NN-2344, L895645, YM-440, R-119702, AJ9677, repaglinide, nateglinide, KADI 129, APR-H039242, GW-409544, KRP297, AC2993, Exendin-4, LY307161, NN2211, and/or LY315902.

[00168] In one particular embodiment, the antidiabetic agent is metformin (e.g., provided in the form of its HCl salt). Certain such dosage forms are provided as bilayer tablets, with saxagliptin in one layer and metformin in the other layer. Other such dosage forms are provided with saxagliptin and dapagliflozin together in one layer, e.g., in a monolithic tablet. In another particular embodiment, the antidiabetic agent is dapagliflozin (e.g., provided in the form of its (S)-propylene glycol solvate monohydrate, as described in U.S. Patent no. 7,919,598, which is hereby incorporated herein by reference in its entirety). Certain such dosage forms are provided as bilayer tablets, with saxagliptin in one layer and dapagliflozin in the other layer. Other such dosage forms are provided with saxagliptin and dapagliflozin together in one layer, e.g., in a monolithic tablet. Certain compressible formulations of metformin and of dapagliflozin suitable for use in such embodiments of the invention are described, for example, in U.S. Patent no. 7,851,502 and in U.S. Patent Application Publications nos. 2012/0294936, 2012/0282336 and 2013/0034606, each of which is hereby incorporated herein by reference in its entirety. [00169] In other embodiments, a dosage form as described herein further includes an anti-obesity agent. The anti-obesity agent can be provided, for example, in the same tablet layer as the saxagliptin HC1, or in a separate tablet layer (e.g., as the second layer in a bilayer tablet). For example, in certain embodiments, the anti- obesity agent is a beta 3 adrenergic agonist, a lipase inhibitor, a serotonin (and dopamine) reuptake inhibitor, a thyroid receptor beta compound, an anorectic agent, and/or a fatty acid oxidation upregulator. In certain such embodiments, the anti- obesity agent is orlistat, ATL-962, AJ9677, L750355, CP331648, sibutramine, topiramate, axokine, dexamphetamine, phentermine, phenylpropanolamine, famoxin, and/or mazindol.

[00170] In other embodiments, a dosage form as described herein further includes a lipid modulating agent. The lipid modulating agent can be provided, for example, in the same tablet layer as the saxagliptin HC1, or in a separate tablet layer (e.g., as the second layer in a bilayer tablet). For example, in certain embodiments, the lipid modulating agent is an MTP inhibitor, an HMG CoA reductase inhibitor, a squalene synthetase inhibitor, a fibric acid derivative, an upregulator of LDL receptor activity, a lipoxygenase inhibitor, an ACAT inhibitor, a cholesteryl ester transfer protein inhibitor, or an ATP citrate lyase inhibitor. In certain such embodiments, the lipid modulating agent is pravastatin, lovastatin, simvastatin, atorvastatin, rosuvastatin, cerivastatin, fluvastatin, nisvastatin, visastatin, fenofibrate, gemfibrozil, clofibrate, implitapide, CP-529,414, avasimibe, TS-962, MD-700, and/or LY295427.

[00171] In one particular embodiment, the lipid modulating agent is atorvastatin. Certain such dosage forms are provided as bilayer tablets, with saxagliptin in one layer and atorvastatin in the other layer. Other such dosage forms are provided with saxagliptin and atorvastatin together in one layer, e.g., in a monolithic tablet. In another particular embodiment, the lipid modulating agent is rosuvastatin. Certain such dosage forms are provided as bilayer tablets, with saxagliptin in one layer and rosuvastatin in the other layer. Other such dosage forms are provided with saxagliptin and rosuvastain together in one layer, e.g., in a monolithic tablet.

[00172] As the person of ordinary skill in the art will appreciate, the saxagliptin can be provided at any desired dosage level in the dosage forms described herein, e.g., in the range of about 0.1 mg to about 200 mg. For example, saxagliptin can be provided in a dosage range of about 0.5 to about 100 mg saxagliptin, about 1 to about 50 mg saxagliptin, or even about 2 to about 20 mg saxagliptin per tablet (i.e., in the form of the crystalline saxagliptin HC1 salt form). For example, in certain

embodiments, saxagliptin is provided in amount of about 1 mg, about 2.5 mg, about 5 mg, about 10 mg, or about 20 mg per tablet.

[00173] In certain embodiments, a tablet dosage form includes a compressed layer that includes (e.g., consists essentially of), in compressed form, in the range of about 0.2 wt% to about 50 wt% of a particulate pharmaceutical composition as described herein; about 0 wt% to about 30 wt% of one or more additional active pharmaceutical ingredients (e.g., as described above); 0 wt% to about 99% of one or more fillers (e.g., as described above); 0 wt% to about 20 wt% of one or more disintegrants (e.g., as described above); 0 wt% to about 20 wt% of one or more binders (e.g., as described above); 0 wt% to about 10 wt% of one or more glidants and/or antiadherents (e.g., as described above); and 0 wt% to about 5 wt% of one or more lubricants (e.g., as described above). For example, in one embodiment a tablet dosage form includes a compressed layer that includes (e.g., consists essentially of), in compressed form, in the range of about 0.5 wt% to about 20 wt% of a particulate pharmaceutical composition as described herein; about 0 wt% to about 20 wt% of one or more additional active pharmaceutical ingredients (e.g., as described above); 0 wt% to about 97% of one or more fillers (e.g., as described above); 0 wt% to about 15 wt% of one or more disintegrants (e.g., as described above); 0 wt% to about 15 wt% of one or more binders (e.g., as described above); 0 wt% to about 5 wt% of one or more glidants and/or antiadherents (e.g., as described above); 0 wt% to about 3 wt% of one or more lubricants (e.g., as described above) and optionally, 0.01 wt% to about 5 wt% of a stabilizing agent (e.g., alginic acid). The compressed layers including the particulate pharmaceutical composition as described herein can be, for example, in the form of a monolithic tablet; or as one layer of a multilayer tablet (e.g., a bilayer tablet).

[00174] For example, in certain embodiments, a tablet dosage form includes a compressed layer that includes (e.g., consists essentially of), in compressed form, in the range of about 0.2 wt% to about 20 wt% of a particulate pharmaceutical composition as described herein; 50 wt% to about 99% of one or more fillers (e.g., as described above); 0 wt% to about 15 wt% of one or more disintegrants (e.g., as described above); 0 wt% to about 20 wt% of one or more binders; 0 wt% to about 10 wt% of one or more glidants and/or anti adherents (e.g., as described above); 0 wt% to about 5 wt% of one or more lubricants (e.g., as described above) and optionally, and optionally, 0. 1 wt% to about 5 wt% of a stabilizing agent (e.g., alginic acid). Such a compressed layer can be used as a single drug-containing layer in a monolithic saxagliptin tablet, or, in other embodiments, a layer in a multilayer dosage form that combines saxagliptin with another (e.g., metformin, dapagliflozin, atorvastatin, rosuvastatin, preferably metformin and dapagliflozin). For example, in one embodiment, a tablet dosage form includes a compressed layer that includes (e.g., consists essentially of), in compressed form, in the range of about 0.2 wt% to about 10 wt% of a particulate pharmaceutical composition (e.g., a saxagliptin HC1 particulate pharmaceutical formulation) as described herein; about 80 to about 97.75 wt% of a filler (e.g., a calcium phosphate filler); about 2 to about 10 wt% of a disintegrant (e.g., crospovidone); and about 0.05 to about 2 wt% of a lubricant (e.g., sodium stearyl fumarate or magnesium stearate). In another embodiment, a tablet dosage form includes a compressed layer that includes (e.g., consists essentially of), in compressed form, in the range of about 0.2 wt% to about 10 wt% of a particulate pharmaceutical composition (e.g., a saxagliptin HC1 particulate pharmaceutical formulation) as described herein; about 0.2 wt% to about 20 wt% of one or more additional active pharmaceutical ingredients (e.g., dapagliflozin, metformin, atorvastatin or

rosuvastatin, preferably dapagliflozin and metformin); about 70 to about 97.55 wt% of a filler (e.g., a calcium phosphate filler); about 2 to about 10 wt% of a disintegrant (e.g., crospovidone); and about 0.05 to about 2 wt% of a lubricant (e.g., sodium stearyl fumarate or magnesium stearate). In another embodiment, a tablet dosage form includes a compressed layer that includes (e.g., consists essentially of), in compressed form, in the range of about 0.2 wt% to about 10 wt% of a particulate pharmaceutical composition (e.g., a saxagliptin HC1 particulate pharmaceutical formulation) as described herein; about 0.2 wt% to about 20 wt% of one or more additional active pharmaceutical ingredients (e.g., dapagliflozin and metformin); about 70 to about 97.55 wt% of a dibasic calcium phosphate anhydrous; about 2 to about 10 wt% of talc; and about 0.05 to about 2 wt% of stearic acid; and optionally, 0. 01 wt% to about 5 wt% of alginic acid.

[00175] The person of ordinary skill in the art can use conventional formulation and tabletting processes in making the tablets of the present invention. [00176] In another embodiment, the particulate pharmaceutical composition is filled in one or more capsules, alone or together with other excipients or active pharmaceutical ingredients, to form one or more capsule dosage forms. For example, the compressible formulations described herein with respect to tablet dosage forms can be filled into gelatin capsules in an uncompressed form.

[00177] One embodiment of a particular method for making a particulate pharmaceutical composition is shown in the process flow diagram of FIG. 4. The polymer, here, poly(vinyl pyrrolidone-co-vinyl acetate) having a weight ratio of 60% vinyl pyrrolidone and 40% vinyl acetate (Kollidon® VA 64) (62.5 g, an amount that is 50% of the weight of the saxagliptin free base monohydrate to be added) is charged to a crystallization vessel. The polymer is dissolved in a mixture of isopropanol (10 Vol), aqueous HCl (1.5 equivalents, 12.1 N, providing 0.4 Vol water), water (0.6 Vol) and methyl tert-butyl ether (4 Vol) at 30 °C. Once the polymer is dissolved, saxagliptin free base monohydrate (form H-l) (125 g) is charged directly to the acidified polymer solution. The saxagliptin free base reacts with the HCl to form a crystalline saxagliptin HCl salt (mono HCl H2-1 form) in a slurry-to-slurry conversion. The slurry is cooled to 20 °C over a period in the range of 30-60 min. A micrograph of the crystalline saxagliptin HCl salt is provided as FIG. 5.

[00178] Once the batch temperature reaches 20 °C, the slurry of the crystalline saxagliptin HCl salt is wet milled while methyl tert-butyl ether (20 Vol) is added over the course of 30 minutes. The addition of the methyl tert-butyl ether precipitates the polymer, which coats the crystalline saxagliptin HCl particles to form particles as a slurry in the liquid mixture of the solvent and the antisolvent. A micrograph of the particles is provided as FIG. 6. Advantageously, the wet milling prevents the agglomerates from growing to sizes >100 μπι in size and aids in the formation of a more uniform polymer coating on the saxagliptin HCl particles. FIG. 7 provides an x-ray diffraction pattern of particles in the slurry of particles after wet milling.

[00179] As described above, the liquid phase of the slurry of the particles includes a mixture of the solvent and the antisolvent. The inventors have determined that if too much solvent is present in the liquid wetting the particles while they are dried, a hard cake can form. As the hard cake is difficult to filter, it can be desirable to avoid its formation. Accordingly, in certain embodiments of the methods described herein, recovering the particles from the slurry includes separating a substantial amount of the liquid from the slurry of the particles while retaining the particles in a slurry form; washing the particles with a wash liquid; and separating the particles from

substantially all liquid. Conveniently, to separate a substantial amount of the liquid from the slurry while retaining it in a slurry form, the slurry can be allowed to settle and the particle-free liquid can be decanted. The washing liquid can be, for example, an antisolvent. In other embodiments, the washing liquid can be a liquid that does not substantially swell the one or more polymers of the particles. In this process, the particles can remain in a slurry while as solvent is being washed away, helping to keep particles from sticking together. The washing step can be performed multiple times, with particle-free liquid being removed between washes.

[00180] Thus, in certain embodiments of the methods described herein (and in the embodiment of FIG. 4), after polymer precipitation and wet milling, the slurry is allowed to settle and the liquid above the level of the slurry is removed by

decantation. A volume of methyl tert-butyl ether approximately equal to the volume of the settled slurry is added to the slurry to dilute the isopropanol in the

solvent/anti solvent liquid. After washing the slurry with the methyl tert-butyl ether, the particulate matter is allowed to settle and the liquid above the slurry line is removed by decantation. This wash/decantation procedure is repeated, then a volume of methyl tert-butyl ether approximately equal to the volume of the remaining slurry is mixed into the slurry, and the slurried particles are filtered and washed with a methyl tert-butyl ether displacement wash.

[00181] In certain embodiments of the methods described herein, the initial drying of the wet particles is performed at a temperature below 37 °C for at least 4 hours. The temperature can then be raised up to over 40 °C to finish the drying. The inventors have determined that initial drying at higher temperatures can cause the formation of hard lumps.

[00182] Accordingly, in the embodiment of FIG. 4, the wet cake of saxagliptin HCl/polymer particles is dried by blowing 30 °C nitrogen through the wet cake for several hours, after which time the temperature of the drying nitrogen stream is raised to 40-50 °C. During drying, the particles are intermittently mixed with minimal agitation. When drying is complete, the particulate pharmaceutical composition is provided as a soft, nearly lump-free powder. [00183] FIG. 8 provides an x-ray diffraction pattern of the dried particulate pharmaceutical composition, as compared to a powder x-ray diffraction pattern of crystalline saxagliptin mono HCl salt 0.75 hydrate form HO.75-3. These data demonstrate that the saxagliptin HCl in the dried particulate pharmaceutical composition is crystalline, but that it has changed form from the mono HCl salt dihydrate H2-1 form to the mono HCl salt 0.75 hydrate form HO.75-3 form. Tablets can be compressed from the particulate pharmaceutical formulation without a change in crystalline form.

[00184] Light scattering experiments were performed to determine particle size distribution. The particle size data is provided in the graph of FIG. 9. The particulate pharmaceutical composition had a D ₅₀ value of about 14 μπι, and a D ₉₀ value of about 48 μτη.

[00185] Raman imaging was used to visualize the individual particles of the particulate pharmaceutical formulation. FIG. 10A is a micrograph of the saxagliptin within a particle (i.e., selecting Raman parameters to detect only the saxagliptin); saxagliptin is visualized as red color. FIG. 10B is a micrograph of the polymer within the same particle (i.e., selecting Raman parameters to detect only the polymer);

polymer is visualized as green color. FIG. IOC is a micrograph of the polymer under conditions in which all materials are detected; only a slight amount of red

(corresponding to saxagliptin) bleeds through the green color corresponding to the polymer, indicating that the polymer substantially coats the saxagliptin HCl crystals. The thickness of the polymer coating on the saxagliptin is estimated to be about 1 μπι, as shown in the Raman image of FIG. 11.

[00186] The particulate pharmaceutical composition described with respect to FIGS. 4-11 was blended with calcium phosphate (A-Tab ^® brand); crospovidone and sodium stearyl fumarate and tableted. Specifically, each tablet (200 mg total weight) contains the particulate pharmaceutical composition (2 wt%), calcium phosphate (92 wt%), crospovidone (5 wt%), and magnesium stearate (1 wt%). As the person of ordinary skill in the art will appreciate, in other embodiments, calcium phosphate may be fully or partially replaced with other diluents such as lactose, microcrystalline cellulose and sugar. As the person of ordinary skill in the art will appreciate, in other embodiments, the crospovidone may be fully or partially replaced with other disintegrants such as sodium croscarmellose or sodium starch glycolate. As the person of ordinary skill in the art will appreciate, in other embodiments, the magnesium stearate may be fully or partially replaced with other lubricants such as sodium stearyl fumarate. Of course, the person of ordinary skill in the art will recognize that other formulations, especially tablet formulations may be made using the particulate pharmaceutical compositions as described herein. All ingredients are pre-blended to form a uniform mixture, followed by roller compaction, milling, tablet compression, and film coating, to form film-coated tablets.

[00187] Tablets were stored open to the environment at 40 °C and 75% relative humidity. Stability data were compared to historical data for the commercial saxagliptin HCl tablets (trade name ONGLYZA ^® ), which are made by a spray coating process (see generally U.S. Patent no. 7,951,400). Data are provided in bar graph form in FIG. 12. The stability results indicated that tablets made using the methods described herein can be sufficiently stable for therapeutic use. In certain

embodiments, tablets made using the methods described herein can provide improved stability over spray-coated tablets.

[00188] Another embodiment of a particular method for making a particulate pharmaceutical composition is shown in the process flow diagram of FIG. 13. The polymer, here, poly(vinyl pyrrolidone-co-vinyl acetate) (Kollidon® VA 64) (250 g, an amount that is 50% of the weight of the saxagliptin free base monohydrate to be added) is charged to a crystallization vessel. The polymer is dissolved in a mixture of isopropanol (10 Vol), aqueous HCl (1.5 equivalents, 12.1 N, providing 0.4 Vol water), water (0.6 Vol) and methyl tert-butyl ether (4 Vol) at 30 °C. Once the polymer is dissolved, saxagliptin free base monohydrate (form H-l) (500 g) is charged directly to the acidified polymer solution. The saxagliptin free base reacts with the HCl to form a crystalline saxagliptin HCl salt (mono HCl salt H2-1 form) in a slurry-to-slurry conversion. The slurry is cooled to 20 °C over a period in the range of 30-60 min.

[00189] Once the batch temperature reaches 20 °C, the slurry of the crystalline saxagliptin HCl salt is wet milled while methyl tert-butyl ether (20 Vol) is added over the course of one hour. The addition of the methyl tert-butyl ether precipitates the polymer, which coats the crystalline saxagliptin HCl particles to form particles as a slurry in the liquid mixture of the solvent and the antisolvent. The mixture of liquids was decanted from the solids of the slurry as described above, and the particles were washed twice with methyl tert-butyl ether as described above. The particles were filtered and dried at 30 °C with blowing nitrogen and intermittent agitation. The final mass of the particulate pharmaceutical composition was 741 g, provided as a lump- free, apparently non-electrostatic powder.

[00190] Three batches according to the general procedure of FIG. 13 were prepared. The particle size distributions of the three batches were D ₁₀ in the range of 4.3 to 4.7 μπι, D50 in the range of 13.7 to 16.1 μπι, and D 0 in the range of 44.4 to 48.5 μπι. The bulk densities of the three batches ranged from 0.19 to 0.20 g/mL. The batches exhibited satisfactory powder flow.

[00191] The particulate pharmaceutical composition made as described in FIG. 13 was formed into tablets. To form monolithic 5 mg saxagliptin tablets, the particulate pharmaceutical composition (3.0 wt%) made as described in FIG. 13 was combined with dibasic calcium phosphate anhydrous (A-Tab ^® ) (91.9 wt%), crospovidone (5 wt%) and sodium stearyl fumarate (0.1 wt%). The mixture was blended in a bin blender; milled in a Comil apparatus, and blended again in a bin blender to form a compressible formulation of saxagliptin HCl. This compressible formulation was tableted using a Piccola bi-layer press to form a 300 mg tablet, which was coated with Opadry ^® II at a level of 3 wt%.

[00192] To form 5 mg saxagliptin/ 1000 mg extended release metformin bilayer tablets, the compressible saxagliptin HCl formulation described above (300 mg) was tableted with 1450 mg of an extended release metformin HCl compressible formulation containing metformin HCl with 0.5% magnesium stearate (69.31 wt%), carboxymethylcellulose sodium (34.48 wt%), hypromellose 2208 (27.10 wt%) and magnesium stearate (0.14 wt%), as well as sufficient water for tabletting in a Piccola bi-layer press to form a 1750 mg bilayer tablet, which was coated with Opadry ^® II at a level of 3 wt%.

[00193] Stability data for the monolithic 5 mg saxagliptin tablets (compared to commercial ONGLYZA ^® tablets) and the 5 mg saxagliptin/ 1000 mg extended release metformin bilayer tablets (as compared to KOMBIGLYZE ^® XR tablets) are presented in FIG. 14. The tablets were aged for 6 months under closed conditions at 40 °C and 75%) relative humidity. The data indicate that the tablets in which the saxagliptin is in a compressed tablet layer have similar storage performance to the reference tablets, in which saxagliptin is in a spray-coated coating. [00194] To form 2.5 mg saxagliptin/10 mg dapagliflozin bilayer tablets, the particulate pharmaceutical composition (2.1 wt%) made as described in FIG. 12 was combined with dibasic calcium phosphate anhydrous (A-Tab ^® ) (92.15 wt%), crospovidone (5 wt%) and magnesium stearate (0.75 wt%). The mixture was blended in a bin blender; milled in a Comil apparatus, and blended again in a bin blender to form a compressible formulation of saxagliptin HC1. This compressible formulation (200 mg) was tableted with 200 mg of a dapagliflozin compressible formulation containing dapagliflozin (S)-propylene glycol solvate hydrate (6.15 wt%, to provide 5 wt% dapagliflozin), lactose anhydrous (20 wt%), crospovidone (4 wt%), silicon dioxide (1.5 wt%), microcrystalline cellulose (67.35 wt%) and magnesium stearate (1 wt%) in a Piccola bi-layer press to form a 400 mg bilayer tablet, which was coated with Opadry ^® II at a level of 3 wt%.

[00195] To form monolithic 2.5 mg saxagliptin/10 mg dapagliflozin tablets, the particulate pharmaceutical composition (2.1 wt%) made as described in FIG. 12 was combined with dapagliflozin (S)-propylene glycol solvate hydrate (6.15 wt%), dibasic calcium phosphate anhydrous (A-Tab ^® ) (84.5 wt%), crospovidone (5 wt%) and magnesium stearate (0.75 wt%). The mixture was blended in a bin blender; milled in a Comil apparatus, and blended again in a bin blender to form a compressible formulation of saxagliptin HC1 and dapagliflozin. This compressible formulation was tableted using a Piccola bi-layer press to form a 200 mg tablet, which was coated with Opadry ^® II at a level of 3 wt%.

[00196] Stability data for the 2.5 mg saxagliptin/10 mg dapagliflozin bilayer tablets and the monolithic 2.5 mg saxagliptin/10 mg dapagliflozin tablets (compared to commercial ONGLYZA ^® tablets and the monolithic 5 mg saxagliptin tablets described above) are presented in FIG. 15. The tablets were aged for 4 weeks under closed conditions at 40 °C and 75% relative humidity. The data indicate that the saxagliptin/dapagliflozin combination tablets have acceptable storage performance.

[00197] Another embodiment of a particular method for making a particulate pharmaceutical composition is shown in the process flow diagram of FIG. 17. The polymer, here, poly(vinyl pyrrolidone-co-vinyl acetate) having a weight ratio of 60% vinyl pyrrolidone and 40% vinyl acetate (Kollidon® VA 64) (15 g) is charged to a crystallization vessel. The polymer is dissolved in a mixture of isopropanol (10 Vol), aqueous HC1 (0.5 Vol, 1.5 equivalents) and methyl tert-butyl ether (4 Vol) at 30 °C. Once the polymer is dissolved, saxagliptin free base monohydrate (form H-l) (20 g) is charged directly to the acidified polymer solution. The saxagliptin free base reacts with the HCl to form a crystalline saxagliptin HCl salt in a slurry-to- slurry

conversion. The slurry is cooled, then methyl tert-butyl ether (18 Vol) is added to precipitate the polymer with wet milling. The slurry is then filtered and the collected particulate matter is washed with methyl tert-butyl ether and dried to provide the particulate pharmaceutical composition. The powder x-ray dispersion pattern of the particulate pharmaceutical composition is provided as the upper trace in FIG. 16, demonstrating that the saxagliptin is provided in the form P-4.

[00198] Another embodiment of a particular method for making a particulate pharmaceutical composition is shown in the process glow diagram of FIG. 19. The polymer, here, poly(vinyl pyrrolidone-co-vinyl acetate) having a weight ratio of 60% vinyl pyrrolidone and 40% vinyl acetate (Kollidon® VA 64) (12 g) is charged to a crystallization vessel. The polymer is dissolved in a mixture of isopropanol (8 Vol), aqueous HCl (0.75 Vol, 1.5 equivalents) and methyl tert-butyl ether (3 Vol) at 30 °C. Once the polymer is dissolved, saxagliptin free base monohydrate (form H-l) (20 g) is charged directly to the acidified polymer solution. The saxagliptin free base reacts with the HCl to form a crystalline saxagliptin HCl salt in a slurry-to- slurry

conversion. The slurry is cooled, then methyl tert-butyl ether (20 Vol) is added to precipitate the polymer with wet milling. The slurry is then filtered and the collected particulate matter is washed with methyl tert-butyl ether and dried to provide the particulate pharmaceutical composition. The powder x-ray dispersion pattern of the particulate pharmaceutical composition is provided as the upper trace in FIG. 18. The upper trace is a combination of the middle trace (form Q-l) and the lower trace (mono HCl 0.75 hydrate form HO.75-3), demonstrating that the saxagliptin is provided as a mixture of form Q-l and mono HCl 0.75 hydrate form HO.75-3.

[00199] Another embodiment of a particular method for making a particulate pharmaceutical composition is shown in the process flow diagram of FIG. 21. The polymer, here, poly(vinyl pyrrolidone-co-vinyl acetate) having a weight ratio of 60% vinyl pyrrolidone and 40% vinyl acetate (Kollidon® VA 64) (150g) is charged to a crystallization vessel. The polymer is dissolved in a mixture of isopropanol (10 Vol), aqueous HCl (1 Vol, 1.5 equivalents) and methyl tert-butyl ether (4 Vol) at 30 °C. Once the polymer is dissolved, saxagliptin free base monohydrate (form H-l) (300 g) is charged directly to the acidified polymer solution. The saxagliptin free base reacts with the HC1 to form a crystalline saxagliptin HC1 salt in a slurry-to- slurry

conversion. The slurry is cooled, then methyl tert-butyl ether (18 Vol) is added to precipitate the polymer with wet milling. The slurry is then filtered and the collected particulate matter is washed with methyl tert-butyl ether and dried to provide the particulate pharmaceutical composition. The powder x-ray dispersion pattern of the particulate pharmaceutical composition is provided as the upper trace in FIG. 20. The upper trace is a combination of the middle trace (form Q-l) and the lower trace (mono HC1 0.75 hydrate form HO.75-3), demonstrating that the saxagliptin is provided as a mixture of form Q-l and mono HC1 0.75 hydrate form HO.75-3.

[00200] The free base monohydrate (Form H-l) of saxagliptin can be made in a number of different ways. Three examples are provided below:

First example of preparation of saxagliptin free base monohydrate (Form H-l):

[00201] 18 g of Boc-protected saxagliptin (IA) was charged into a three-neck flask equipped with mechanical stirrer, thermocouple, and N ₂ gas inlet. Ethyl acetate (180 ml) was added to dissolve the Boc-protected saxagliptin. 14.8 ml of 37%

hydrochloric acid was added and the mixture agitated at 23 °C for 4 hours at which time the reaction was completed. 180 ml ethyl acetate was added and the reaction flask was cooled to 16°C.

[00202] Anhydrous potassium carbonate (60 g) was added to the cooled reaction flask and the resulting mixture was agitated at room temperature for 2 hours. The resulting solid was filtered, the cake washed with 100 ml ethyl acetate, and the filtrate was collected and concentrated to ~ 61 g. 1 ml water was added dropwise to the filtrate and the mixture was agitated until crystals started to form. Another 1 ml water was added dropwise to the filtrate and the mixture agitated at room temperature for 16 hours. The mixture was filtered and dried to yield 10.5 g of free base monohydrate of saxagliptin (form H-l), yield 77% (purity 99.2 AP).

Second example of preparation of saxagliptin free base monohydrate (Form H-l):

[00203] 300 g (0.723 mol) of Boc-protected saxagliptin (IA) (potency 90.6%) was charged into a three-neck 12 L flask equipped with mechanical stirrer, probe, and N ₂ gas inlet. Methylene chloride (3 L) and methanol (288 ml, 7.23 mol), and 36% HC1 (288 ml, 3.5 mol, 4.8 eq) were added. The mixture was stirred for 18 hours and the reaction was completed (the Boc-protected saxagliptin in CH ₂ C1 ₂ was < 1 mg/ml). The mixture formed two phases; the top aqueous layer was collected (the bottom methylene chloride layer was discarded). Methylene chloride (6 L) and water (720 ml) were added to the recovered aqueous phase. NaOH (5N) (~ 600 ml) was added dropwise to the recovered aqueous phase to adjust pH to 9.0 ~ 10.5. Solid NaCl (120 g) was added and the mixture was agitated for 20 minutes. A phase split occurred and the bottom methylene chloride layer was collected (the top aqueous layer was discarded). The methylene chloride layer was washed with 1% ammonium chloride brine solution (450 ml). A phase split occurred and the bottom methylene chloride layer was collected (the top aqueous layer (pH = 7.8) was discarded). Ethyl acetate ~ 4 L) was added while methylene chloride was distilled off at 25°C/50 mm Hg. The distillation was stopped when the final volume reached 2.5 L. The remaining liquid was polish filtered to remove solid NaCl. Concentration was continued to ~ 1 Kg (~ 170 g) of free base of saxagliptin monohydrate in 1 L ethyl acetate). Water was added dropwise (17 ml) and the mixture held for ~ 10 minutes when crystallization started. Another 17 ml of water was added and the resulting slurry was agitated for 30 minutes. The slurry was filtered and the recovered cake washed with ethyl acetate (150 ml). The washed cake was dried at room temperature under vacuum to give 186 g of saxagliptin free base monohydrate (form H-l) yield 81%.

Third example of preparation of saxagliptin free base monohydrate (Form H-l):

[00204] A mixture of 1 g Boc-protected saxagliptin (IA), 1 ml isopropanol, 1 ml water and 0.28 ml of concentrated HC1 was heated to 65°C and held at 65°C for 90 minutes. To the heated mixture was added 2 ml water and the mixture was cooled to 25°C. 12 ml methylene chloride was added and the pH of the mixture was adjusted to ~ 9 using 0.2 ml 10N sodium hydroxide and 0.4 ml 25% potassium carbonate. 1.25 g sodium chloride was dissolved in the pH adjusted solution. The solution separated into two layers and the rich organic phase was collected.

[00205] The rich organic phase was atmospherically concentrated to 3 ml to remove residual water. The concentrated organic was cooled to 25 °C, 2 ml ethyl acetate was added and the solution was polish filtered to remove residual sodium chloride. 0.05 ml water was added to the solution which was held for 30 minutes to form a slurry of crystals of product. 0.21 ml water was added to the crystal containing slurry which was subjected to constant volume distillation at less than 30°C by adding 2 ml ethyl acetate at approximately the rate of distillation. 0.08 ml water was added and the mixture cooled to ~ 5°C and held for 30 minutes. The resulting slurry was filtered and the cake washed with a mixture of 2 ml ethyl acetate and 0.04 ml water. The mixture was dried at 40°C (maintaining the dew point about -8°C) and the crystals of saxagliptin free base monohydrate recovered.

[00206] A comparative sample of crystalline monohydrochloride salt of saxagliptin dihydrate (Form H2-1) can be prepared as described below:

[00207] BOC-protected saxagliptin (4.19 g, 10.1 mmol) was dissolved in anhydrous CH ₂ CI ₂ (25 mL) and cooled to 0°C and treated with trifluoroacetic acid (15 mL) and stirred for 2.5 h at ambient temperature. The solvents were removed by rotary evaporation and the residue was chased with toluene (5 mL) and dried under reduced pressure. Tituration with Et ₂ 0 afforded the trifluoroacetic acid salt of saxagliptin as a white solid (3.92 g, 90%).

[00208] The trifluoroacetic acid salt of saxagliptin (50 mg) was dissolved in 0.2 mL water. The pH of the resulting aqueous solution was adjusted to approximately 9.4 with IN NaOH. Aqueous and organic layers were formed. The aqueous layer was extracted with 2 x 0.5 mL methylene chloride. The combined rich methylene chloride solution was washed with 1 mL water.

[00209] 0.116 mL (1 equiv.) of a solution of IN HC1 was added to the rich methylene chloride solution. A clear solution formed which was evaporated to dryness leaving a solid.

[00210] 0.2 mL of ethanol was mixed with the solid to dissolve the solid. The resulting ethanol solution was heated to 45°C and 0.3 mL of t-butylmethyl ether was added. The solution turned into a slurry.

[00211] The slurry was cooled from 45 °C to 20°C over one hour. The cooled slurry was filtered and the resulting filter cake was dried at room temperature under vacuum to obtain monohydrochloride salt of saxagliptin dihydrate (form H2-1).

[00212] A comparative sample of crystalline monohydrochloride salt of saxagliptin 0.75 hydrate (Form HO.75-3) can be prepared as described below:

[00213] A single crystal of saxagliptin HC1 dihydrate (form H2-1) is heated at 50°C for 2 hours. A single crystal of saxagliptin hydrochloride salt (form 0.75-3) containing 0.75 equiv. H ₂ 0 form is recovered.

[00214] In the fourth and fifth examples set forth below; a stable drug product was defined as the concentration of cyclic ami dine in the drug product of < 0.5% w/w of saxagliptin after 3 months of storage under 40°C and 75% RH in a designated container closure system. More specifically, a drug product where the concentration of cyclic amidine in the drug product of < 0.25% w/w of saxagliptin after 9 weeks of storage under 40°C and 75% RH in a designated container closure system.

Fourth example of preparation of saxagliptin and dapagliflozin combination product:

[00215] Monolithic tablet formulations that contain saxagliptin CPT and dapagliflozin in the same tablet blend were prepared using both direct compression

(DC) and roller compaction (RC) processes. The composition of these formulations is listed in Error! Reference source not found, set forth below.

Table 1. Composition of Saxa CPT/Dapa monolithic layer used in the preparation of

Saxa CPT/Dapa/Met XR bilayer tablets.

[00216] This formulation contains 2.5 mg of saxagliptin (Saxa) and 5 mg of dapagliflozin (Dapa) in a core tablet that has a compression weight of 300 mg.

Batches 66A and 66B were prepared by the DC process, while batches 66C and 66D were prepared by the RC process. In addition, batches 66A and 66C contain 5% w/w alginic acid (AA) while batches 66B and 66D do not contain AA. These Saxa CPT/Dapa monolithic core tablet formulations were utilized to prepare bilayer Saxa CPT/Dapa/metformin (Met) XR core tablets by compressing the Saxa CPT/Dapa formulation as the first layer with Met XR formulation as the second layer of the core tablets. These tablets were coated with a conventional aqueous PVA-containing Opadry II coating system to produce coated Saxa CPT/Dapa/Met XR FDC tablets. The preparation process for these batches is illustrated in FIG . These tablets were packaged in 200 cc high density polyethyelene (HDPE) bottles with 30 tablet count per bottle, three desiccants (each desiccant containing 1.2 g silica gel and 0.8 g charcoal), rayon coil filler, and induction sealed. Accelerated stability testing was carried out by storing the sealed bottles at different temperature and humidity environmental conditions and sampling at different time points, followed by testing for impurities as an indication of the quality of drug product.

[00217] The effect of the Met XR layer, compression force, and coating on the stability of saxagliptin was assessed by concurrent accelerated stability testing of (a) uncoated Saxa CPT/Dapa/Met XR bilayer FDC tablets and (b) uncoated Saxa CPT/Dapa monolithic core tablets. Results of accelerated stability studies are summarized in FIG. 23, FIG.24 and FIG 25.

[00218] FIG. 23 shows Saxa degradants in Saxa CPT/Dapa/Met XR bilayer film coated tablets at 40°C/75% RH in induction sealed HDPE bottles with desiccants at 4 week (4w) and 6 week (6w) time points. Formation of cyclic amidine (A) and total (B) saxagliptin impurities is plotted for direct compression (DC) and roller compaction (RC) batches prepared with and without alginic acid (AA). The results indicate a stabilizing effect of AA on the Saxa impurities in the tablets. The stabilizing effect of AA on Saxa impurities was evident in the DC formulation earlier than in the RC formulation.

[00219] FIG. 24 shows Saxa degradants in Saxa CPT/Dapa monolithic (M) core (uncoated) tablets in comparison with Saxa CPT/Dapa//Met XR bilayer (BL) core (uncoated) tablets at 40°C/75% RH in induction sealed HDPE bottles with desiccants at 6 week (6w) time point. Formation of cyclic amidine (A) and total (B) saxagliptin impurities is plotted for the roller compaction (RC) batch prepared with alginic acid (AA). These data indicate equivalent stability of M and BL tablets, indicating no significant impact of the Met XR layer on the stability of Saxa in the Saxa CPT/Dapa layer. In addition, since the M tablets were compressed at 7-10 kN compression force while the BL tablets were compressed at 45-50 kN compression force, this data indicates that compression force does not have a significant impact on the stability of saxagliptin.

[00220] FIG. 25 shows Saxa degradants in Saxa CPT/Dapa/Met XR bilayer (BL) coated tablets after 4 weeks compared with core (uncoated) tablets after 9 weeks of storage 40°C/75% RH in induction sealed HDPE bottles with desiccants. Formation of cyclic amidine (A) and total (B) saxagliptin impurities is plotted for the direct compression (DC) and roller compaction (RC) batch prepared with alginic acid (AA). This comparison indicates that the stability of core tablets is improved in comparison to the coated tablets prepared using conventional aqueous PVA-based coating dispersion. The only exception to this phenomenon seems to be the roller compaction batch without alginic acid.

[00221] Formation of higher impurities in the coated bilayer tablets compared to the uncoated (core) bilayer tablets may be attributed to the use of an aqueous film coating system that was not acidified. Saxagliptin hydrochloride, the form of saxagliptin present in the Saxa CPT material, disproportionates into saxagliptin and free hydrochloric acid once dissolved in the water present in the microenvironment. The free base of saxagliptin is more reactive towards the formation of the cyclic amidine impurity. The presence of free water in the microenvironment of the tablets during the preparation or on stability studies can increase the rate of drug degradation. The water activity for the core and coated tablets prepared in this example was < 0.50 at 25°C (FIG. 26). The water activity of < 0.50 at 25 ± 3°C at any time during the preparation and/or storage of the drug product were deemed to produce a stable drug product based on the stability data presented on these four batches.

[00222] Approaches that may be used to mitigate the propensity of saxagliptin disproportionation and degradation in the presence of water in the microenvironment include, but are not limited to:

[00223] Use of an acidified aqueous film coating. The acidification of water that comes in contact with saxagliptin any time during the drug product preparation is expected to prevent the disproportionation of saxagliptin by shifting the equilibrium towards the salt form. Saxagliptin is known to be stable in acidified aqueous solutions.

[00224] Use of non-aqueous film coating. Avoiding or minimizing the contact of saxagliptin with water during drug product preparation.

[00225] Drug product preparation processes that do not involve the use of water. Thus, DC or RC processes are preferred over wet granulation (WG) approaches since the DC and RC processes do not involve the use of water during drug product preparation.

[00226] Preparing the drug product under conditions and controls such that the finished drug product has a water activity of < 0.50 at 25 ± 3°C at any time during the preparation and/or storage of the drug product. Minimization of water activity contributes to the minimization of exposure of saxagliptin to free or mobile water, which may lead to solubilization, disproportionation, and degradation of saxagliptin. Fifth example of preparation of stable monolithic tablets of saxagliptin:

[00227] Monolithic core tablet formulations that contain saxagliptin and dapagliflozin in the same tablet blend were prepared using Saxa CPT, A-Tab ^® , talc, stearic acid with or without one or more of (a) low substituted hydroxypropyl cellulose (L-HPC), (b) E5 grade of hydroxypropyl methylcellulose (HPMC-E5), and (c) crospovidone. The formulation compositions of these batches are shown in Error! Reference source not found, set forth below. These batches were prepared by a dry (without the use of water) direct compression process illustrated in FIG. 26.

[00228] Table 2. Composition of Saxa CPT/Dapa monolithic core tablets.

[00229] After preparation, the drug product was packaged in induction sealed HDPE bottles with desiccants and placed on accelerated stability studies at 40°C/75% RH environmental conditions. The concentration of cyclic amidine in the drug product was analyzed after 4 weeks of storage. This data is shown in FIG. 27. [00230] The total concentration of cyclic amidine in these batches was calculated as the combined concentration of the cyclic amidine epimer and cyclic amidine itself since cyclic amidine epimer is a precursor on the degradation pathway of saxagliptin to cyclic amidine.

[00231] This stability data indicates that HPMC-E5, L-HPC, and crospovidone stabilize the monolithic core tablets of saxagliptin prepared using the Saxa CPT material. Furthermore, addition of HPMC-E5 alone in batch 56C is seen to stabilize saxagliptin in the drug product towards the formation of cyclic amidine.

[00232] Comparing batches 56C with batch 60A, the presence of crospovidone in the formulation appears to destabilize saxagliptin towards the formation of the cyclic amidine degradation pathway, leading to higher concentration of cyclic amidine in the drug product. However, although the use of crospovidone in the drug product may be less than ideal, this disintegrant may be needed in the formulation to enable tablet disintegration and drug release. The extent of formation of cyclic amidine (total impurities < 0.2% after 4 weeks at 40°C/75% RH under closed conditions) was deemed acceptable for this drug product.

[00233] Comparing the concentration of cyclic amidine in batches 60A with 60B, the former prepared with HPMC-E5 and crospovidone, while the latter prepared with L-HPC, the total cyclic amidine concentration is comparable across the two batches. Both these batches were stable under these storage conditions, forming < 0.2% of cyclic amidine in 4 weeks. L-HPC has the polymer backbone that is present in HPMC, while having different behavior in the presence of water. Therefore, either of these formulations may be used for drug product preparation from the viewpoint of saxagliptin degradation.

[00234] Therefore, the compositions of compressible saxagliptin drug product that contain one or more of A-tab ^® (or other chemical forms of calcium phosphate), talc, stearic acid, HPMC-E5, crospovidone, or L-HPC were considered acceptable. These tablets can optionally also contain one or more additional compatible active pharmaceutical ingredients, such as dapagliflozin used in the current formulation.

[00235] The role of talc and stearic acid as glidant and lubricant, respectively, are considered as preparation aids. Therefore, their need for inclusion in the formulation and concentration depends on the preparation of the saxagliptin (or its co-processed form utilized) formulation. Similarly, crospovidone and L-HPC are considered as disintegants. Therefore, their need for inclusion in the formulation and concentration depends on the drug release properties of the saxagliptin (or its co-processed form utilized) formulation. For example, a saxagliptin formulation that utilizes a co- processed form of saxagliptin that ensures disintegration of the drug product and dissolution of saxagliptin may not require the addition of disintegrants as excipients in the drug product.

[00236] Alternatively, saxagliptin (present as is or in any of its salt, crystalline, co- crystal, or co-processed forms) may be prepared with any one or more of the qualitative ingredients listed in Error! Reference source not found, set forth above in the presence or absence of another compatible active pharmaceutical ingredient (API) in the same composition (monolithic tablet) or separated in a different composition (e.g., bilayer tablets). For example, saxa CPT may be compressed into very small tablets (ca 50 mg) using only A-tab ^® or only L-HPC as the excipient. Alternatively, such small tablets may be combined with tablets of another API, such as dapagliflozin, in a dosage form (such as beads filled in a capsule).

Fifth example of compatibility of common excipients in compressed saxagliptin tablets:

[00237] Monolithic saxa CPT core tablets containing saxa CPT in the presence of A-tab ^® as a diluent; 1% magnesium stearate as a lubricant; and one common pharmaceutical excipient at 5% w/w concentration was used to assess compatibility of common excipients with compressible saxagliptin tablets. The compressed tablets were stored for 2 weeks at 40°C under closed conditions in sealed lyophilization vials without desiccants or under open conditions at 40°C/75% RH environmental conditions. The results of this excipient compatibility study are summarized in FIG. .

[00238] This stability data indicates that compressible saxagliptin formulations were more stable with crospovidone than croscarmellose sodium. The compressible saxagliptin formulations were also more stable with stearic acid compared to magnesium stearate as a lubricant. In addition, talc and dapagliflozin do not seem to impact the stability of compressible saxagliptin tablets.

[00239] Further, the foregoing description of embodiments has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. As the person of skill in the art will recognize, many modifications and variations are possible in light of the above teaching. It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the scope of the disclosure. Thus, it is intended that the present disclosure cover the modifications and variations of this disclosure provided they come within the scope of the claims and their equivalents.