Crystalline form A of obeticholic acid and preparation method thereof

Abstract

The present invention relates to crystalline Form A of obeticholic acid and the preparation method thereof. The present invention provides Form A having characteristic peaks at 2theta value of 4.90.2, 5.20.2, 9.90.2. The present invention provides a novel crystalline form of obeticholic acid, which has good stability, good processability and other favorable properties, and is suitable for storage and usage as a final product. In addition, the preparation method is simple, low cost, and has great value for the future optimization and development of obeticholic acid.

Claims

1. A crystalline Form A of Obeticholic acid, is characterized in that, the X-ray powder diffraction pattern of the crystalline Form A shows characteristic peaks at 2theta values of 4.90.2, 5.20.2, and 9.90.2using CuKradiation.

2. The crystalline Form A according to claim 1, characterized in that, the X-ray powder diffraction pattern of the crystalline Form A further shows characteristic peaks at 2theta values of 7.20.2, 7.70.2, and 10.50.2.

3. The crystalline Form A according to claim 1, characterized in that, the X-ray powder diffraction pattern of the crystalline Form A further shows characteristic peaks at 2 theta values of 6.20.2, 12.50.2, and 15.70.2.

4. The crystalline Form A according to claim 1, characterized in that the X-ray diffraction pattern of the crystalline Form A is substantially the same as depicted in FIG. 1.

5. The crystalline Form A according to claim 1, characterized in that the differential scanning calorimetry analysis curve of said crystalline Form A shows an endothermic peak when heated to 90-92 C.

6. The crystalline Form A according to claim 1, characterized in that said crystalline Form A is a hydrate.

7. The crystalline Form A according to claim 1, characterized in that, the water content in said crystalline Form A is 4 wt % -13 wt %.

8. A process for preparing crystalline Form A of Obeticholic acid according to claim 1, comprising: adding Obeticholic acid powder into a crystallizing solvent to affect crystallization, wherein the crystallizing solvent is a) ethyl acetate, b) a mixed solvent of ethyl acetate and n-heptane, c) a mixed solvent of methyl ethyl ketone and n-heptane, or d) a mixed solvent of chloroform and n-heptane.

9. The process according to claim 8, comprising the step of: suspending and slurrying; heating and cooling; evaporating or adding sequentially each solvent of the mixed solvent.

10. A pharmaceutical composition comprising the crystalline Form A of Obeticholic acid according to claim 1, and pharmaceutically acceptable carriers.

11. A method of treating a patient having primary biliary cirrhosis (PBC) or nonalcoholic steatohepatitis (NASH) comprising the administration of the crystalline Form A of Obeticholic acid according to claim 1 to the patient.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows an XRPD pattern of crystalline Form A of obeticholic acid;

(2) FIG. 2 shows a DSC thermogram of crystalline Form A of obeticholic acid;

(3) FIG. 3 shows a TGA thermogram of crystalline Form A of obeticholic acid.

DETAILED DESCRIPTION OF THE INVENTION

(4) The present invention will be further explained by the specific embodiments, but are not intended to limit the scope of the present invention. The skilled in the art can make improvements to the preparation methods and the used instruments within the scope of the claims, and those improvements should be considered as falling into the scope of the present invention. Accordingly, the protective scope of the present invention patent should be defined by the appended claims.

(5) In the following embodiments, the experimental methods were implemented generally in accordance with conventional conditions or conditions recommended by the manufacturers; the obeticholic acid powder was prepared by the known methods, for example, prepared by the method disclosed in patent WO2013192097.

(6) The abbreviations used in the invention are explained as follows: XRPD: X-ray Powder Diffraction DSC: Differential Scanning Calorimetry TGA: Thermal Gravimetric Analysis

(7) X-ray powder diffraction pattern in the present invention was acquired by a Panalytical Empyrean X-ray powder diffractometer. The parameters of the X-ray powder diffraction method of the present invention were as follows: X-ray Reflection: Cu, K K1 (): 1.540598; K2 (): 1.544426 K2/K1 intensity ratio: 0.50 Voltage: 45 (kV) Current: 40 (mA) Scan range: from 3.0 degree to 40.0 degree
The pattern of differential scanning calorimetry (DSC) in the present invention was acquired by a TA Q200. The parameters of the differential scanning calorimetry (DSC) method of the present invention were as follow: Heating rate: 10 C./min Purge gas: nitrogen.
The pattern of thermal gravimetric analysis (TGA) in the present invention was acquired by a TA Q5000. The parameters of the thermal gravimetric analysis (TGA) method of the present invention were as follow: Heating rate: 10 C./min; Purge gas: nitrogen.

EXAMPLE 1

(8) Preparation Method of Crystalline Form A of Obeticholic Acid:

(9) 216.3 mg of obeticholic acid powder was added into 5.0 mL of a mixed solvent of ethyl acetate and n-heptane with a volume ratio of 1:9 to obtain a suspension. The suspension was stirred at room temperature for 48 hours, filtered, and the filter cake was dried in a vacuum drying oven at 25 C. overnight, and tested to be crystalline Form A.

(10) The XRPD data of the crystalline Form A produced in this example is listed in Table 1. The XRPD pattern is displayed in FIG. 1, the DSC thermogram plot is displayed in FIG. 2, and the TGA thermogram plot is displayed in FIG. 3.

(11) In addition, the purity of obeticholic acid Form A measured by evaporative light scattering method is 99.54%.

(12) Form A after storage under 5 C. for 90 days was analyzed by XRPD, and the XRPD pattern was substantially the same as FIG. 1.

(13) TABLE-US-00001 TABLE 1 2 theta d spacing Relative intensity % 4.95 17.87 55.14 5.26 16.79 51.49 6.22 14.20 100.00 7.22 12.24 39.00 7.66 11.54 49.18 8.90 9.93 42.81 9.36 9.44 38.30 9.95 8.89 43.47 10.45 8.46 30.64 10.97 8.06 20.12 12.51 7.08 99.90 14.89 5.95 32.18 15.69 5.65 62.49 15.96 5.55 37.49 16.47 5.38 49.44 17.23 5.15 30.92 17.95 4.94 28.12 18.87 4.70 36.32 19.56 4.54 31.45 20.57 4.32 21.24 21.34 4.16 15.50 22.70 3.92 7.95 23.46 3.79 6.10 24.72 3.60 6.51 25.11 3.55 7.62

EXAMPLE 2

(14) Preparation Method of Crystalline Form A of Obeticholic Acid Crystalline:

(15) 39.2 mg of obeticholic acid powder was added into 5.0 mL of a mixed solvent of methyl ethyl ketone and n-heptane with a volume ratio of 1:9 to obtain a suspension. The suspension was stirred in a thermostat incubator at 50 C. for 100 min, and filtered to give a clear solution. The clear solution was slowly cooled to 5 C. at a cooling rate of 0.1 C./min. A large amount of solid precipitated during the cooling, and centrifuged to give a solid. The solid was dried in a vacuum drying oven at 25 C. overnight, and tested to be crystalline Form A.

(16) The XRPD data of the Form A obtained from this example is listed in Table 2.

(17) TABLE-US-00002 TABLE 2 2 theta d spacing Relative intensity % 3.23 27.34 79.22 4.91 17.98 100.00 5.24 16.85 92.44 6.22 14.20 87.87 7.19 12.30 30.89 7.66 11.54 45.98 8.90 9.94 43.19 9.35 9.46 17.61 9.92 8.92 18.05 10.49 8.43 15.67 12.46 7.11 66.09 15.72 5.64 19.96 16.47 5.38 32.72 18.92 4.69 8.47

EXAMPLE 3

(18) Preparation Method of Crystalline Form A of Obeticholic Acid:

(19) 9.6 mg of obeticholic acid powder was added into 0.4 mL of chloroform, and filtered to obtain a clear solution. The clear solution was stirred on a magnetic stirrer at 500 rpm at room temperature, and 0.6 mL of n-heptane was added dropwise to obtain a suspension. The suspension was stirred on a magnetic stirrer at 500 rpm for 2 days at room temperature to precipitate a large amount of solid, and centrifuged to give a solid. The solid was dried in a vacuum drying oven at 25 C. overnight, and tested to be crystalline Form A.

(20) The XRPD data of the Form A obtained from this example is listed in Table 3.

(21) TABLE-US-00003 TABLE 3 2 theta d spacing Relative intensity % 3.09 28.64 53.73 4.92 17.96 86.44 5.24 16.86 78.78 6.22 14.20 100.00 7.21 12.25 31.06 7.66 11.54 40.10 8.90 9.94 29.26 9.37 9.44 19.04 9.93 8.91 17.08 10.51 8.42 14.71 12.50 7.08 60.41 15.72 5.64 28.09 16.48 5.38 26.45 17.95 4.94 12.8 18.97 4.68 12.44 19.58 4.53 9.40

EXAMPLE 4

(22) Preparation Method of Crystalline Form A of Obeticholic Acid:

(23) 16.5 mg of obeticholic acid powder was added into 1.0 mL of ethyl acetate and filtered to give a clear solution. The clear solution was slowly evaporation at room temperature to give Form A.

(24) The XRPD data of the Form A obtained from this example is listed in Table 4.

(25) TABLE-US-00004 TABLE 4 2 theta d spacing Relative intensity % 4.92 17.98 15.35 5.26 16.81 11.38 6.22 14.20 100.00 7.18 12.31 12.50 7.67 11.52 8.62 8.89 9.95 12.05 9.36 9.44 12.85 9.90 8.93 14.55 10.49 8.44 6.59 12.50 7.08 51.93 15.72 5.64 35.72 16.41 5.40 29.91 17.16 5.17 9.60 19.00 4.67 13.12 19.56 4.54 9.80 20.51 4.33 6.77 24.87 3.58 1.50

EXAMPLE 5

(26) The Comparative Study of Stability of Crystalline Form A of Obeticholic Acid and Crystalline Form C in WO2013192097:

(27) 10.5 mg of crystalline Form C of obeticholic acid in patent WO2013192097 was added into 0.2 mL of a mixed solvent of ethyl acetate and n-heptane with a volume ratio of 1:9 to obtain a suspension. The suspension was stirred at 500 rpm in a thermostat at 25 C. for 24 hours, and centrifuged to give a solid which was tested by XRPD.

(28) The results show that obeticholic acid crystalline Form C disclosed by patent WO2013192097 was transferred to crystalline Form A of the present invention in the mixed solvent of ethyl acetate and n-heptane. Thus it can be seen that, crystalline Form A is more stable than crystalline Form C in patent WO2013192097.

(29) The examples described above are only for illustrating the technical concepts and features of the present invention, and intended to make those skilled in the art being able to understand the present invention and thereby implement it, and should not be concluded to limit the protective scope of this invention. Any equivalent variations or modifications according to the spirit of the present invention should be covered by the protective scope of the present invention.