Novel co-crystals of enagliflozin

Abstract

The invention relates to a eutecticum of enagliflozin. According to the enagliflozin eutectic disclosed by the invention, the solubility of enagliflozin in artificial gastric juice and artificial intestinal juice is improved. The increased solubility of Enagliflozin may be particularly advantageous for the development of oral formulations for indications requiring high dose administration. The Enagliflozin eutectic also shows stability equivalent to that of the existing Enagliflozin crystal form, so that the Enagliflozin eutectic is very valuable as an active pharmaceutical ingredient of Enagliflozin. Furthermore, the co-crystal of the present invention has a longer half-life and a higher systemic exposure (AUCinf) compared to the existing crystalline form A, resulting in prolonged efficacy, and thus can be effectively used for developing various indications and / or formulations requiring these properties.

Description

Technical Field

[0001] The present invention relates to a co-crystal of empagliflozin (enavogliflozin). Background Art

[0002] The selection of preferred solid forms of active ingredients, such as their pharmaceutically acceptable salts, co-crystals, polymorphs, and pseudopolymorphs, has a very important impact on the development of the production process of active pharmaceutical ingredients and the dosage form design and formulation of pharmaceutical products.

[0003] Specifically, salts, co-crystals, and polymorphs of active pharmaceutical ingredients affect the final stage of the manufacture of active pharmaceutical ingredients, namely the recrystallization yield, process speed, and purity in the recrystallization and purification processes. Depending on the size or shape of the crystals, the speed of the crystallization process may vary, which affects productivity and manufacturing costs.

[0004] In addition, in terms of drugs, physicochemical properties such as hygroscopicity, stability, solubility, particulate fluidity, and dissolution rate are affected by their salts, co-crystals, polymorphs, or pseudopolymorphs, and thus become factors determining the production process, production and storage conditions, and shelf life of pharmaceutical products.

[0005] Meanwhile, when the bioavailability of a drug is affected by the physical properties of the active pharmaceutical ingredient, more attention is required in the selection of its salts, co-crystals, polymorphs, or its pseudopolymorphs or its polymorphs, which is very important in terms of technology development and drug approval.

[0006] The object of the present invention is to explore a novel co-crystal of empagliflozin, and to develop a co-crystal that can maximize pharmacological activity by analyzing physicochemical properties, thereby improving low solubility (which is a drawback of existing polymorphs).

[0007] Sodium-glucose cotransporter 2 (SGLT-2) is a transporter that, together with sodium-glucose cotransporter 1 (SGLT-1), is responsible for the reabsorption of excess blood glucose in the kidneys, with SGLT-2 playing a major role. Therefore, when an SGLT-2 inhibitor blocks the SGLT-2 transporter, the amount of blood glucose excreted in the urine increases, ultimately reducing the blood glucose level and releasing heat from the blood glucose, resulting in weight loss.

[0008] Due to this effect, one of the drugs developed as an SGLT-2 inhibitor and usable as a therapeutic agent for type 2 diabetes is empagliflozin represented by the following Chemical Formula 1, which is disclosed in Korean Patent Application Laid-Open No. 2014-0022086 (Patent Document 1).

[0009] [Chemical Formula 1]

[0010]

[0011] In addition, the crystal form of empagliflozin and a method for preparing the crystal form of empagliflozin have been disclosed in Korean Unexamined Patent Application Publication No. 2017-0142904 (Patent Document 2).

[0012] However, the crystal form of empagliflozin disclosed in Korean Unexamined Patent Application Publication No. 2017-0142904 (Patent Document 2) has the disadvantage of low solubility of 0.25 mg / mL.

[0013] Therefore, the present inventors have studied cocrystals capable of increasing the solubility of empagliflozin, and have confirmed that a specific cocrystal form also has excellent stability during the preparation process and can increase the solubility, thereby completing the present invention.

[0014] [Related Art Documents]

[0015] [Patent Documents]

[0016] Patent Document 1. Korean Unexamined Patent Application Publication No. 2014-0022086

[0017] Patent Document 2. Korean Unexamined Patent Application Publication No. 2017-0142904 Summary of the Invention

[0018] [Technical Problem]

[0019] An object of the present invention is to provide a novel cocrystal of empagliflozin and a method for preparing the same, the novel cocrystal having excellent stability and excellent solubility. The present invention also relates to providing a pharmaceutical composition comprising the novel cocrystal of empagliflozin as an active ingredient.

[0020] [Technical Solution]

[0021] One aspect of the present invention provides a novel empagliflozin cocrystal represented by the following Chemical Formula 2 and a method for preparing the same.

[0022] [Chemical Formula 2]

[0023]

[0024] The present inventors attempted to design a cocrystal by selecting amino acids and organic acids having high solubility and rich in NH, N, O, and OH to overcome the low solubility of empagliflozin.

[0025] The amino acids and organic acids selected for the preparation of co-crystals include aspartic acid, acetylsalicylic acid, citric acid, nicotinic acid, nicotinamide, β-cyclodextrin, propylene glycol, phenylalanine, lactose monohydrate, L-proline, urea, L-lysine, L-pyroglutamic acid, orotic acid monohydrate, maleic acid, malic acid, L-ascorbic acid, fumaric acid, succinic acid, malonic acid, oxalic acid trihydrate, L-tartrate, sodium chloride, L-serine, L-arginine, L-valine, L-methionine, threonine, glycine, L-alanine, L-cysteine, L-tryptophan, L-asparagine, L-isoleucine, L-glutamine, L-histidine, and L-glutamic acid.

[0026] Attempts were made to prepare co-crystals of empagliflozin using the above 38 types of amino acids and organic acids, ensuring three types of co-crystals, such as empagliflozin / proline co-crystals, empagliflozin / methionine co-crystals, and empagliflozin / proline hydrate co-crystals.

[0027] As a result of evaluating the solubility of empagliflozin / proline co-crystals, empagliflozin / methionine co-crystals, and empagliflozin / proline hydrate co-crystals in pH 1.2 and pH 6.8 eluents, the three types of co-crystals, namely empagliflozin / proline co-crystals, empagliflozin / methionine co-crystals, and empagliflozin / proline hydrate co-crystals, showed higher solubility than the crystalline form of empagliflozin within the first 2 hours, confirming the improvement of the initial solubility through co-crystals.

[0028] However, during the scale-up (), the empagliflozin / proline hydrate co-crystal had a problem of low reproducibility in preparing co-crystals, and due to the low melting point of 106 °C, it was expected that the empagliflozin / methionine co-crystal would reduce stability. As a result of the stress stability test at 60 °C for 4 weeks, it was confirmed that within only 4 weeks, the purity of the empagliflozin / methionine co-crystal decreased by approximately 3%, showing lower stability than the crystalline form of empagliflozin and the empagliflozin / proline co-crystal. Therefore, it was confirmed that the empagliflozin / proline co-crystal had the best stability and solubility.

[0029] For experimental optimization, a method for reproducibly preparing empagliflozin / proline co-crystals was established. The empagliflozin / proline co-crystals prepared by this method had an approximately 21% increase in solubility in artificial gastric juice, an approximately two-fold or more increase in solubility in artificial intestinal juice, and an increase in initial solubility compared to the existing crystalline form of empagliflozin. In addition, due to the above dissolution characteristics, improved effects were confirmed in oral absorption effects and actual mouse pharmacokinetic experiments.

[0030] Thus, by using the empagliflozin / proline co-crystal of the present invention, an oral formulation with improved solubility of empagliflozin can be prepared. The increased solubility of empagliflozin may be beneficial for the development of oral formulations for indications that require high-dose administration.

[0031] The empagliflozin / proline co-crystal is formed by hydrogen bonding between one molecule of empagliflozin and one molecule of proline (L-proline) in a 1:1 ratio.

[0032] Since the hydrogen bond between proline, which has high solubility in water, and empagliflozin forms a co-crystal, when proline dissolves due to its interaction with proline, empagliflozin also dissolves in water, thus increasing the solubility in water and in artificial gastric juice and artificial intestinal juice.

[0033] The empagliflozin / proline co-crystal of the present invention is a novel solid form of empagliflozin that has not been reported.

[0034] In one embodiment of the present invention, there is provided an empagliflozin / proline co-crystal, characterized in that it provides an X-ray powder diffraction pattern having four or more, such as 4, 5, 6, 7, 8 or more diffraction peaks at 2[θ] values selected from 4.72±0.2, 6.81±0.2, 7.93±0.2, 8.59±0.2, 14.75±0.2, 15.21±0.2, 17.23±0.2, 18.80±0.2, 21.19±0.2, 24.42±0.2 and 27.29±0.2 in powder X-ray diffraction (PXRD) analysis.

[0035] In particular, the X-ray powder diffraction pattern has diffraction peaks at 2[θ] values selected from 6.81±0.2, 8.59±0.2, 14.75±0.2, 17.23±0.2 and 18.80±0.2.

[0036] More specifically, the empagliflozin / proline co-crystal is characterized by an X-ray powder diffraction pattern having peak positions that match those listed in Table 1 below.

[0037] [Table 1]

[0038]

[0039] In another embodiment of the present invention, in differential scanning calorimetry (DSC), the empagliflozin / proline co-crystal shows an endothermic onset temperature of the endothermic peak at 217.71 °C ± 3 °C and an endothermic peak temperature at 219.42 °C ± 3 °C. The empagliflozin / proline co-crystal according to the present invention is in a form in which 1 equivalent of proline is combined with 1 equivalent of empagliflozin. According to nuclear magnetic resonance (NMR) analysis, it can be confirmed that in the 1H-NMR spectrum, the empagliflozin / proline co-crystal consists of one molecule of empagliflozin and one molecule of proline.

[0040] Another aspect of the present invention provides a method for preparing an empagliflozin / proline co-crystal.

[0041] Although not limited thereto, the empagliflozin / proline co-crystal is prepared by a method including the following steps: (a) mixing empagliflozin and an organic solvent, and adding proline to the resulting mixture; (b) stirring the product obtained in step (a); and (c) vacuum drying the product obtained in step (b) to obtain the empagliflozin / proline co-crystal.

[0042] The method for preparing the empagliflozin / proline co-crystal of the present invention will be described in detail step by step below.

[0043] (a) Mix empagliflozin with an organic solvent and add proline

[0044] First, the method of the present invention includes mixing solid empagliflozin and an organic solvent, and adding proline to the resulting mixture. There is no particular limitation on the physicochemical form of the solid empagliflozin used herein. For example, according to Experimental Example 4 in Korean Unexamined Patent Application Publication No. 2017-0142904, the solid may be crystalline form A, crystalline form B, crystalline form C, or crystalline form D of empagliflozin having the following X-ray diffraction spectra reported, or amorphous empagliflozin.

[0045] Crystalline form A: A crystalline form having an X-ray diffraction (XRD) spectrum with peaks at 2[θ] values selected from 6.2° ± 0.2°, 7.2° ± 0.2°, 8.8° ± 0.2°, 17.6° ± 0.2°, 19.0° ± 0.2°, 22.5° ± 0.2°, and 25.1° ± 0.2°.

[0046] Crystalline form B: A crystalline form having an X-ray diffraction (XRD) spectrum with peaks at 2[θ] values selected from 7.0° ± 0.2°, 14.9° ± 0.2°, 17.7° ± 0.2°, 18.8° ± 0.2°, 20.6° ± 0.2°, 21.8° ± 0.2°, and 23.5° ± 0.2°.

[0047] Polymorph C: A polymorph having an X-ray diffraction (XRD) spectrum with peaks at 2[θ] values selected from 5.6° ± 0.2°, 7.3° ± 0.2°, 15.7° ± 0.2°, 17.2° ± 0.2°, 18.9° ± 0.2°, 21.2° ± 0.2°, and 21.9° ± 0.2°.

[0048] Polymorph D: A polymorph having an X-ray diffraction (XRD) spectrum with peaks at 2[θ] values selected from 5.5° ± 0.2°, 7.2° ± 0.2°, 15.3° ± 0.2°, 17.2° ± 0.2°, 17.6° ± 0.2°, 18.9° ± 0.2°, and 21.1° ± 0.2°.

[0049] Each of polymorphs A, B, C, and D is determined by an X-ray diffraction spectrum that has four or more, such as 4, 5, 6, 7, 8 or more, peaks at the indicated 2[θ] values.

[0050] The organic solvent in step (a) can dissolve empagliflozin and proline well, and any organic solvent capable of producing an empagliflozin / proline co-crystal can be used. The organic solvent that has been proven to be effective in producing the empagliflozin / proline co-crystal in high yield and removing excess proline can be one or more types of organic solvents selected from the group consisting of: methanol, ethanol, isopropanol, 1-butanol, acetone, tetrahydrofuran, acetonitrile, ethyl acetate, dichloromethane, methyl tert-butyl ether (MTBE), toluene, and dioxane. The organic solvent can be a single solvent or a mixed solvent.

[0051] Preferably, the organic solvent is one or more selected from the group consisting of methanol, ethanol, isopropanol, and acetone. More preferably, the organic solvent is ethanol.

[0052] The volume of the organic solvent in step (a) can be 10 times or more the weight of empagliflozin, such as 10 to 200 times, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 120, 150, or 200 times the weight of empagliflozin.

[0053] The amount of the organic solvent used can vary depending on the type of the organic solvent or whether it is used as a single solvent or a mixed solvent. For example, in the case of methanol, dioxane or tetrahydrofuran, a co-crystal can be produced with only 10 times the weight of the solvent of empagliflozin. In the case of ethanol, isopropanol, 1-butanol, acetone or acetonitrile, a co-crystal can be produced with 50 times the weight of the solvent of empagliflozin. When ethyl acetate is used as the solvent, due to the low solubility of empagliflozin, crystallization is required after heating at a level of 50 times the weight of empagliflozin. Dichloromethane cannot dissolve empagliflozin well, so the amount required is 100 times the weight of empagliflozin. MTBE and toluene are difficult to dissolve empagliflozin, so the amount required is 150 times the weight of empagliflozin or more.

[0054] Therefore, by considering the solubility of empagliflozin in the solvent and the degree of co-crystal formation, the type and mixture of the organic solvent can be selected, and the amount of the organic solvent can be adjusted. If necessary, heating can be carried out simultaneously to dissolve empagliflozin.

[0055] In another embodiment of the present invention, the organic solvent can be ethanol and can be used in a volume of 10 to 60 times the weight of empagliflozin.

[0056] In another embodiment of the present invention, proline is added in a molar ratio of 1 to 1.5 equivalents relative to empagliflozin.

[0057] (b) Stir the resulting product

[0058] Next, the method of the present invention includes stirring the product obtained in step (a).

[0059] In another embodiment of the present invention, the stirring in step (b) can be carried out at 0 to 50 °C, such as 15 to 40 °C, preferably 15 to 30 °C, and more preferably 20 to 25 °C.

[0060] In another embodiment of the present invention, the stirring in step (b) can be carried out for 0.5 to 24 hours, preferably 1 to 12 hours, and more preferably 4 to 8 hours.

[0061] (c) Vacuum dry the resulting product to obtain the empagliflozin / proline co-crystal

[0062] Finally, the method of the present invention includes vacuum drying the product obtained in step (b) and obtaining the empagliflozin / proline co-crystal.

[0063] In another embodiment of the present invention, the vacuum drying in step (c) can be carried out at 30 to 65 °C, preferably 40 to 55 °C, and more preferably 45 to 50 °C for 8 to 12 hours.

[0064] In this way, an empagliflozin / proline co-crystal with 1 equivalent of proline bound to 1 equivalent of empagliflozin can be prepared as an SGLT-2 inhibitor, which can be used as a therapeutic agent for type 2 diabetes. It regulates blood glucose by inhibiting the reabsorption of blood glucose in the kidneys and excreting blood glucose via urine.

[0065] The present invention also provides a pharmaceutical composition comprising an empagliflozin / proline co-crystal as an active ingredient and a pharmaceutically acceptable carrier.

[0066] The pharmaceutical composition can be used for treating or preventing diabetes, but the present invention is not limited thereto.

[0067] The empagliflozin / proline co-crystal according to the present invention can be administered in various oral and parenteral dosage forms in clinical administration and is prepared using diluents or excipients such as fillers, supplements, binders, wetting agents, disintegrants or surfactants commonly used in formulations.

[0068] [Beneficial effects]

[0069] The empagliflozin / proline co-crystal of the present invention increases the solubility of empagliflozin in artificial gastric juice and artificial intestinal juice. The increased solubility of empagliflozin may be particularly beneficial for the development of oral formulations for indications that require high-dose administration. In addition, the stability of the empagliflozin / proline co-crystal is comparable to the stability of the existing crystal forms of empagliflozin, making it very valuable as an active pharmaceutical ingredient of empagliflozin. In addition, the empagliflozin / proline co-crystal of the present invention exhibits a longer half-life and a higher in vivo exposure (AUC inf ) than the existing crystal form A, which allows for a longer duration of efficacy and can therefore be used for the development of various indications and / or formulations that require them. [Description of the drawings]

[0070] Figure 1 Shows the results of the H-nuclear magnetic resonance (NMR) spectrum of the empagliflozin / proline co-crystal prepared in Preparation Example 2.

[0071] Figure 2 Shows the results of the H-NMR spectrum of crystal form A of empagliflozin prepared according to Preparation Example 1.

[0072] Figure 3 Shows the results of the powder X-ray diffraction (PXRD) pattern of the empagliflozin / proline co-crystal prepared in Preparation Example 2.

[0073] Figure 4 Shows the results of the PXRD pattern of crystal form A of empagliflozin prepared in Preparation Example 1.

[0074] Figure 5Shows the results of the differential scanning calorimetry (DSC) curve of the empagliflozin / proline co-crystal prepared according to Preparation Example 2.

[0075] Figure 6 Shows the results of the DSC curves of the empagliflozin / proline co-crystal, proline, and empagliflozin crystal form prepared according to the examples of the present invention.

[0076] Figure 7 Shows the comparison of the solubility of the empagliflozin / proline co-crystal and the empagliflozin crystal form prepared according to the examples of the present invention in artificial intestinal fluid. Detailed Description of the Invention

[0077] [Invention Mode]

[0078] Hereinafter, with reference to the detailed description of the exemplary embodiments and the drawings, the advantages and features of the present invention and the method of implementing the present invention can be clearly understood. However, the present invention is not limited to the exemplary embodiments disclosed below and can be implemented in many different forms. These exemplary embodiments are provided only to complete the disclosure of the present invention and fully convey the scope of the present invention to those of ordinary skill in the art, and the present invention should be defined only by the appended claims.

[0079] [Preparation Example 1] Preparation of Crystal Form A of Empagliflozin

[0080] Prepare crystal form A of empagliflozin reported in Experimental Example 4 of Korean Unexamined Patent Application Publication No. 2017-0142904.

[0081] Add ethyl acetate (15 times the weight of crude empagliflozin) to crude empagliflozin, reflux and stir to dissolve, then cool to room temperature. A suspension is formed at room temperature and stirred for an additional 30 minutes. Isopropyl ether (15 times the weight of crude empagliflozin) is added dropwise to the resulting mixture within 30 minutes, and further stirred at room temperature for 30 minutes. The resulting precipitate is filtered, washed with ethyl acetate (twice the weight of crude empagliflozin) at 0 °C, and dried in a vacuum oven (50 °C, 12 hours) to obtain white crystals (yield: 88.3%).

[0082] [Preparation Example 2] Preparation of Empagliflozin / Proline Co-crystal

[0083] Add 300 mg of crystal form A of empagliflozin and 10 mL of ethanol, and then stir at room temperature for 20 minutes. Thereafter, 77.3 mg (1 equivalent) of L-proline is added thereto, and stirred at 20 to 25 °C for 1 hour. The precipitated crystals are filtered under reduced pressure, washed with 1 mL of ethanol, and dried in vacuo at 50 °C for 12 hours to obtain a crystal form of empagliflozin / proline co-crystal with a yield of 78%.

[0084] [Preparation Example 3] Evaluation of 13 Solvents for the Formation of L-Proline Cocrystals

[0085] 100 mg (0.224 mmol, 1 equivalent) of crystalline form A was dissolved in each solvent, L-proline (0.224 mmol, 1 equivalent) was added at room temperature, and the resulting solution was stirred for 1 hour or longer, after which the formation of the proline cocrystal was evaluated.

[0086] [Table 2]

[0087]

[0088]

[0089] In the case of methanol, dioxane, and tetrahydrofuran, even with 10 times the volume of the solvent based on the weight of empagliflozin, empagliflozin was completely dissolved, and when L-proline was added, it precipitated as a cocrystal. In the case of ethanol, isopropanol, 1-butanol, acetone, and acetonitrile, cocrystals were produced even with 50 times the weight of empagliflozin of the solvent.

[0090] It was confirmed that a large amount of ethyl acetate and dichloromethane had to be used to dissolve empagliflozin, and when L-proline was added, it precipitated as a cocrystal. When ethyl acetate was used as the solvent, due to the low solubility of empagliflozin, crystallization was required after heating at 50 times the level of the weight of empagliflozin. Dichloromethane also had difficulty dissolving empagliflozin, and it was confirmed that an amount of dichloromethane 100 times the weight of empagliflozin was required.

[0091] The amount of MTBE or toluene should be 150 times or more the weight of empagliflozin because the solubility of empagliflozin in these solvents is very low, but when L-proline was added, it was confirmed that cocrystals were gradually produced.

[0092] On the contrary, it was confirmed that DMSO easily dissolved the cocrystal, and thus no precipitation was observed.

[0093] Depending on the polarity of the solvent, the amount of the solvent needs to be adjusted according to the solubility. However, in the case where the solvent affects the solubility of empagliflozin, L-proline, and the cocrystal, the proline cocrystal cannot be obtained, but when a certain level of solubility is observed, the proline cocrystal can be protected.

[0094] [Experimental Example 1] NMR Spectrum

[0095] The 1H-NMR spectrum of the crystalline form of empagliflozin obtained according to Preparation Example 2 was detected. As a result, the 1H-NMR spectrum results of the empagliflozin / proline cocrystal as shown Figure 1 were obtained. Figure 2The results of the 1H-NMR spectrum of crystalline form A of empagliflozin in Preparation Example 1 are shown. According to Figure 1 , it can be confirmed that the stoichiometric ratio of empagliflozin / proline is exactly 1:1, and the peaks were integrated to show that the crystalline form of empagliflozin obtained according to Preparation Example 2 is an empagliflozin / proline cocrystal.

[0096] [Experimental Example 2] Powder X-ray diffraction (PXRD)

[0097] PXRD was performed on the empagliflozin / proline cocrystal obtained according to Preparation Example 2 using a Bruker PXRD (30 kV, 10 mA, copper target). 2θ scanning was carried out at a step size of 0.02° from 5° to 40°, and the results in Figure 3 were obtained. Figure 3 The PXRD results shown are significantly different from the PXRD results of crystalline form A of empagliflozin in Preparation Example 1 ( Figure 4 ).

[0098] [Table 3]

[0099]

[0100] [Experimental Example 3] Differential scanning calorimetry (DSC)

[0101] Using a DSC Q20 obtained from TA Corp., DSC was performed on crystalline form A of empagliflozin prepared according to Preparation Example 1 and the empagliflozin / proline cocrystal obtained according to Preparation Example 2 from 30 °C to 300 °C at a scanning rate of 10 °C in nitrogen. Figure 5 The results of the DSC curve of the empagliflozin / proline cocrystal prepared in Preparation Example 2 are shown. In the differential scanning calorimetry (DSC) of the empagliflozin / proline cocrystal, it was confirmed that the empagliflozin / proline cocrystal showed an endothermic onset temperature of the endothermic peak of 217.71 ± 3 °C and an endothermic peak temperature of 219.42 ± 3 °C. Figure 6 The comparative results of the DSC curves of the empagliflozin / proline cocrystal, proline, and crystalline form of empagliflozin prepared according to the examples are shown. This shows that crystalline form A of empagliflozin prepared according to Preparation Example 1 and the empagliflozin / proline cocrystal obtained according to Preparation Example 2 showed significantly different endothermic peaks at their endothermic onset temperatures and endothermic wind temperatures.

[0102] [Experimental Example 4] Evaluation of the polymorphs of the empagliflozin / proline cocrystal

[0103] 1 mL of each solvent in the table below was added to 10 mg of each empagliflozin / L-proline cocrystal, and the resulting solution was allowed to stand for 24 hours in a suspended and dissolved state, and then evaluated for the formation of polymorphs of the empagliflozin / L-proline cocrystal.

[0104] [Table 4]

[0105]

[0106] As a result of the DSC evaluation of the crystals obtained through the above experiments, when water was used, a deformation of polymorph A was obtained, but when other solvents were used, all the crystals were identified as the empagliflozin / L-proline cocrystal with an endothermic onset temperature of approximately 217.71 °C ± 3 °C, and no other polymorphs were found.

[0107] [Experimental Example 5] Evaluation of the solubility of empagliflozin / proline cocrystal

[0108] Due to the poor water solubility of empagliflozin (0.25 mg / mL), proline cocrystals were prepared to improve the water solubility and gastroenteric solubility of empagliflozin. By measuring the solubility in artificial gastric juice and artificial intestinal juice containing a large amount of substances that remained in a dissolved state, it was confirmed that the solubility of the empagliflozin / L-proline cocrystal was improved compared to the empagliflozin polymorph. The results are summarized in Tables 5 and 6 and Figure 7 in.

[0109] [Table 5]

[0110] Solubility in artificial gastric juice (FaSSGF)

[0111]

[0112] [Table 6]

[0113] Solubility in artificial intestinal juice (FaSSIF)

[0114]

[0115] As shown in Tables 5 and 6, the solubility of the empagliflozin / L-proline cocrystal of the present invention in artificial gastric juice and artificial intestinal juice increased compared to the empagliflozin polymorph. In particular, as shown in Tables 6 and Figure 7 it was confirmed that the solubility in artificial intestinal juice increased by about 2 times or more (maintained for up to 2 hours) and remained highly soluble for up to 4 hours. Therefore, the empagliflozin / L-proline cocrystal of the present invention is a novel solid form that can overcome the low water solubility (a problem of the empagliflozin polymorph), and it is expected that a 2-fold improvement in the initial solubility in artificial intestinal juice can significantly improve oral absorption and maximize efficacy. The increased solubility of empagliflozin may be particularly beneficial for the development of oral formulations for indications that require high-dose administration.

[0116] [Experimental Example 6] Comparison of the stress stability between empagliflozin cocrystal and empagliflozin polymorph

[0117] To confirm the possibility of commercializing the empagliflozin / proline co-crystal (Preparation Example 2) of the present invention, the thermal stability of crystalline form A of empagliflozin (Preparation Example 1) as a control was tested at 60 °C for 4 weeks, and then the results were analyzed by high performance liquid chromatography (HPLC). The results are shown in Table 7.

[0118] As shown in Table 7, it was confirmed that the empagliflozin / proline co-crystal and the crystalline form of empagliflozin remained stable and were not affected by purity.

[0119] Therefore, it was confirmed that the thermal stability of the empagliflozin / proline co-crystal was comparable to that of the crystalline form of empagliflozin.

[0120] [Table 7]

[0121] Results of stress stability evaluation, 60 °C, 4 weeks

[0122]

[0123] [Experimental Example 7] Pharmacokinetic evaluation of empagliflozin / proline co-crystal in beagle dogs

[0124] A test was conducted to confirm whether the pharmacokinetic characteristics of the empagliflozin / proline co-crystal were improved in beagle dogs. By setting crystalline form A of empagliflozin as the control group and the proline co-crystal as the comparison group, crystalline form A of empagliflozin and the proline co-crystal were orally administered to male beagle dogs at a dose of 1 mg / kg, and blood samples were collected before administration (0 hour) and at 0.083, 0.25, 0.5, 0.75, 1, 1.5, 2, 4, 6, 8, 12, and 24 hours (a total of 13 times). The blood drug concentration was analyzed by LC-MS / MS using the plasma separated from the collected samples, and pharmacokinetic parameters such as the maximum observed plasma concentration (Cmax), area under the plasma concentration-time curve (AUC last and AUC inf ), time to reach the maximum observed plasma concentration (Tmax), and half-life (T 1 / 2 ) were calculated and interpreted using the WinNonlin 5.0.1 program.

[0125] The results are summarized in Table 8 below.

[0126] [Table 8]

[0127] Pharmacokinetic evaluation of empagliflozin / proline co-crystal in beagle dogs

[0128] Pharmacokinetic parameters Crystal form of empagliflozin Proline co-crystal Tmax (hr) 4.00 5.20 <![CDATA[T 1 / 2 (hr)]]> 5.32 6.10 Cmax (ng / mL)) 482.20 482.60 <![CDATA[AUC last (ng*hr / mL)]]> 4340.69 4428.20 <![CDATA[AUC inf (ng*hr / mL)]]> 4639.38 5341.58

[0129] As shown in Table 8, compared with Form A of empagliflozin, the proline cocrystal of the present invention exhibits a longer time to reach the maximum observed plasma concentration (Tmax) and half-life (T 1 / 2 ), as well as PK exposure parameters such as AUC last and AUC inf . Therefore, due to its longer half-life and higher exposure (AUC inf ) compared to the existing Form A, the proline cocrystal is maintained in the body for a slightly longer time and its efficacy lasts for a longer time. Relative to Form A, these pharmacokinetic characteristics of the proline cocrystal contribute to an extended efficacy, thereby consuming energy to lower blood glucose and potentially increasing metabolism through a secondary effect. Therefore, these pharmacokinetic properties can be used to develop various indications and / or formulations.

Claims

1. An empagliflozin / proline co-crystal, characterized in that it has an X-ray powder diffraction pattern with four or more diffraction peaks at 2[θ] values selected from 4.72 ± 0.2, 6.81 ± 0.2, 7.93 ± 0.2, 8.59 ± 0.2, 14.75 ± 0.2, 15.21 ± 0.2, 17.23 ± 0.2, 18.80 ± 0.2, 21.19 ± 0.2, 24.42 ± 0.2, and 27.29 ± 0.

2.

2. The empagliflozin / proline co-crystal according to claim 1, wherein the X-ray powder diffraction pattern has diffraction peaks at 2[θ] values selected from 6.81 ± 0.2, 8.59 ± 0.2, 14.75 ± 0.2, 17.23 ± 0.2, and 18.80 ± 0.

2.

3. The empagliflozin / proline co-crystal according to claim 1, characterized in that it has an X-ray powder diffraction pattern with peak positions matching those listed in the following table:

4. The empagliflozin / proline co-crystal according to claim 1, in differential scanning calorimetry (DSC), the co-crystal shows an endothermic onset temperature of the endothermic peak at 217.71 °C ± 3 °C and an endothermic peak temperature at 219.42 °C ± 3 °C.

5. The empagliflozin / proline co-crystal according to claim 1, wherein the empagliflozin / proline co-crystal is in a form in which 1 equivalent of proline is combined with 1 equivalent of empagliflozin.

6. A method for preparing the empagliflozin / proline co-crystal according to any one of claims 1 to 5, comprising: (a) mixing empagliflozin and an organic solvent, and adding proline to the resulting mixture; (b) stirring the product obtained in step (a); and (c) vacuum drying the product obtained in step (b) to obtain the empagliflozin / proline co-crystal.

7. The method according to claim 6, wherein the organic solvent is one or more types of organic solvents selected from methanol, ethanol, isopropanol, 1-butanol, acetone, tetrahydrofuran, acetonitrile, ethyl acetate, dichloromethane, methyl tert-butyl ether (MTBE), toluene, and dioxane.

8. The method according to claim 6, wherein the volume of the organic solvent used is 10 to 200 times the weight of empagliflozin.

9. The method according to claim 6, wherein the organic solvent is ethanol and is used in a volume of 10 to 60 times the weight of empagliflozin.

10. A pharmaceutical composition comprising the empagliflozin / proline co-crystal according to any one of claims 1 to 5 as an active ingredient and a pharmaceutically acceptable carrier.

11. The composition according to claim 10, wherein the pharmaceutical composition is for the treatment or prevention of diabetes.

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