STABLE APREMILAST CRYSTALLINE FORM II FREE OF SOLVATE AND METHOD OF MAKING THE SAME

Abstract

A stable Crystalline Form II of non-solvate of Apremilast (Formula I), methods of making Form II, pharmaceutical compositions comprising Form II, and their uses are disclosed. Also discloses are mixed crystals comprising Form Hand Form B and methods of making the same. The crystalline forms are characterized using X-ray powder diffractometry (XRPD), infrared spectroscopy (IR), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TG). As compared with Forms A, B, C, D, E, F, and G reported in prior art references, Apremilast Form II of the present invention is more stable to temperature, light, and humidity, and is more suitable for long term storage; the crystallization solvents are safe and can be easily removed; the Form II has a white or off white appearance, and can be directly used in preparation processing; the preparation methods are simple and easy to reproduce, and are suitable for industrialized production.

##STR00001##

Claims

1. An Apremilast crystalline Form II of Formula I, ##STR00004## characterized in that: i) it has an X-ray powder diffraction pattern (XRPD) comprising the following characterizing absorption peaks at 10.6, 11.2, 12.5, 13.2, 13.5, 13.8, 14.7, 16.2, 17.9, 18.7, 20.2, 20.7, 21.5, 21.9, 22.7, 23.1, 25.2, 25.6, 26.5, 27.0, 27.5, 28.2, 29.1, 29.6, 30.9, 32.0, 33.0, 33.5, 34.2, 34.9, 36.2, 39.6, 40.3, 41.0, 43.8 20±0.2; ii) its differential scanning calorimetry (DSC) shows only one endothermic peak at 150±3° C. between 100-180° C.; iii) its thermal gravimetric analysis (TG) shows that it does not comprise crystallization solvent; iv) it has a melting temperature between146-151° C.

2. The Apremilast crystalline Form II of claim 1, characterized in that it has an X-ray powder diffraction pattern (XRPD) comprising the following characterizing absorption peaks at 11.2, 13.2, 13.5, 13.8, 14.7, 16.2, 17.9, 18.7, 20.2, 20.7, 27.0 20±0.2.

3. The Apremilast crystalline Form II of claim 1, characterized in that it has an X-ray powder diffraction pattern (XRPD) comprising the following five characterizing absorption peaks at 11.2, 13.2, 13.5, 13.8, 14.7 20±0.2.

4. The Apremilast crystalline Form II of claim 1, characterized in that it has an X-ray powder diffraction pattern (XRPD) comprising the following two characterizing absorption peaks at 11.2, 14.7 2θ±0.2.

5. The Apremilast crystalline Form II of claim 1, characterized in that it has similar X-ray powder diffraction pattern (XRPD) as shown in FIG. 2, FIG. 5, FIG. 6, FIG. 8, FIG. 12, FIG. 14, FIG. 16, or FIG. 17.

6. A method for preparing the Apremilast crystalline Form II of claim 1, characterized in using a solvent that is a mixture of acetone and water.

7. The method of claim 6, comprising: i) dissolving Apremilast or solvate thereof in acetone at elevated temperature, then cooling to below 40 ° C.; ii) slowly adding water in an amount of 0.5-3 times the volumes of acetone under stirring, optionally seeding with Form II, and continue stirring for 30-180min; iii) adding water in an amount of 2-6 times the volumes of acetone, stirring for 1-24 hr at 10-60° C.; and iv) filtering and drying to obtain Apremilast crystalline Form II.

8. The method of claim 6, comprising suspending other Apremilast crystals, in acetone/water mixture, heating and stirring for 1-72 h, and cooling, filtering and drying to obtain Apremilast crystalline Form II.

9. A pharmaceutical composition comprising an Apremilast crystalline Form II of claim 1 as an active pharmaceutical ingredient and a pharmaceutically acceptable carrier.

10. The pharmaceutical composition of claim 9, characterized in that the active pharmaceutical ingredient comprises 1-100% of Apremilast crystalline Form II.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0065] The figures included in the present application constitute parts of the specification, and can be used to illustrate the present invention together with the specification and claims.

[0066] FIG. 1: XRPD pattern of Form B;

[0067] FIG. 2: XRPD pattern of Form II (stirring for 4 hs after adding water);

[0068] FIG. 3: TG pattern and DSC pattern of Form II (stirring for 23 hs after adding water);

[0069] FIG. 4: IR pattern of Form II (stirring for 23 hs after adding water);

[0070] FIG. 5: XRPD pattern of Form II (stirring for 23 hs after adding water);

[0071] FIG. 6: XRPD pattern of Form II (stirring for 48 hs at 60° C.);

[0072] FIG. 7: XRPD pattern of Form B (stirring for 48 hs at 60° C.);

[0073] FIG. 8: XRPD pattern of Form II (stirring for 24 hs at 100° C.);

[0074] FIG. 9: XRPD pattern of Form B (stirring for 24 hs at 100° C.);

[0075] FIG. 10: DSC pattern of Form II (stirring for 24 hs at 100° C.);

[0076] FIG. 11: DSC pattern of Form B (stirring for 24 hs at 100° C.);

[0077] FIG. 12: XRPD pattern of the product obtained by suspending Form B in acetone/water and stirring for 36 hs at 70° C.;

[0078] FIG. 13: DSC pattern of the product obtained by suspending Form B in acetone/water and stirring for 36 h at 70° C.;

[0079] FIG. 14: XRPD pattern of the product obtained by suspending Form D in acetone/water and stirring for l0 h at 70° C.;

[0080] FIG. 15: DSC pattern of the product obtained by suspending Form D in acetone/water and stirring for 10 h at 70° C.;

[0081] FIG. 16: XRPD pattern of Form II;

[0082] FIG. 17: XRPD pattern of Form II;

[0083] FIG. 18: XRPD pattern of mixture of Form II and Form B (The ratio is roughly 1:1);

[0084] FIG. 19: Plasma concentration vs. time plot of rats gavaged with 10 mg/kg APST-B;

[0085] FIG. 20: Plasma concentration vs. time plot of rats gavaged with 10 mg/kg APST-II;

[0086] FIG. 21: Plasma concentration vs. time plots of male rats gavaged with 10 mg/kg APST-B and APST-II, respectively;

[0087] FIG. 22: Plasma concentration vs. time plots of female rats gavaged with 10 mg/kg APST-B and APST-II, respectively,

[0088] FIG. 23: Plasma concentration-time curve after beagle dogs being given 30 mg APST-B and APST-II capsules of raw material powder through mouth in single period. (Picture above is constant coordinate, picture below is semilogarithm coordinate)

DEVICES AND TESTING METHODS

[0089] 1. X-ray powder diffraction pattern (XRPD):
Device model: Bruker D8 ADVANCE, X-ray powder diffractometer

[0090] Experiment conditions: optical source: CuKα 40Kv 40mA; divergence slit: 1mm; soller slit: 0.4mm; scan mode: continuous scan; scanned area: 3°˜45′; sampling interval: 0.02° ; scan speed: 8° /min. [0091] 2. Infrared spectroscopy

[0092] Device model: NICOLET 670-FTIR

[0093] Experiment condition: KBr tabletting [0094] 3. DSC parmeters:

[0095] Device model: NETZSCH DSC 204 F1

[0096] Crucible type: alumina crucible (Needle punched)

[0097] Sweep gas: high purity nitrogen, 20 mL/min

[0098] Shielding gas: high purity nitrogen, 60 mL/min

[0099] Temperature increase rate: 10° C./min [0100] 4. TG parmeters

[0101] Device model: NETZSCH TG 209 F1

[0102] Crucible type: aluminium oxide crucible

[0103] Sweep gas: high purity nitrogen, 20 mL/min

[0104] Shielding gas: high purity nitrogen, l0 mL/min

[0105] Temperature increase rate: 10° C/min [0106] 5. melting temperature:

[0107] RD-1 melting temperature tester, Tianjin Xuyang Scientific Instruments Equipment Co., Ltd. [0108] 6. Particle size detection:

[0109] Mastersizer 2000 particle size tester, Malvern Instruments Ltd.

DETAILED DESCRIPTION

[0110] The present invention will be further illustrated by the Examples below. However, the Examples shall not be construed as any limitations on the present invention. Any modification of temperature or ratio of solvents falls into the protection scope of the present patent.

EXAMPLE 1

Apremilast Crystalline Form II

[0111] Apremilast (10.0 g) and acetone 35m1 were added to a three-necked flask and were heated to dissolve, then cooled to below 35° C. 0.5-3.0 volumes of purified water was slowly added, small amount of Form II was added as seed crystal, stirred for 1 h until the product precipitated, then 2 times of purified water by volume (70 ml) was added, stirred at 15-20° C. overnight (totally about 24 h), filtered and rinsed with water, dried at 60° C. to provide about 9.32 g of Apremilast Crystalline Form II, mp:147.2-149.8° C.

EXAMPLE 2

Apremilast Crystalline Form II

[0112] Apremilast (400.0 g) and acetone 1200m1 were added to a three-necked flask and were heated to dissolve. 0.5-3.0 volumes of purified water was slowly added, small amount of Form II was added as seed crystal, stirred for 1 h until the product precipitated, then 2 times of purified water by volume (2.4L) was added, stirred at 10-60° C. overnight (totally about 18 h), filtered and rinsed with water, dried at 60° C. to provide about 392.3 g of Apremilast Crystalline Form II, mp: 147.2-150.2° C.

EXAMPLE 3

Apremilast Crystalline Form B

[0113] Apremilast (10.0 g) and acetone (30 ml ) were added to a three-necked flask and were heated to dissolve, then cooled to below 30° C. 10 ml of purified water was slowly added, cooled and stirred until the product precipitated, stirred for 2 h, then water (100 ml ) was slowly added, kept warm and stirred overnight (about 24 h), filtered and rinsed with water, dried at 60° C. to obtain about 9.45 g of Apremilast Crystalline Form B, mp: 156.2-157.8° C.

EXAMPLE 4

[0114]

TABLE-US-00007 Apremilast Crystalline Form II 30.0 g lactose 200.0 g  microcrystalline cellulose 60.0 g croscarmellose sodium 10.0 g aerosil  4.0 g magnesium stearate  2.0 g

[0115] The main drag was passed through a 200 mesh screen, the filler and disintegrating agent were passed through a 80 mesh screen; prescribed amounts of filler and disintegrating agent were weighted and mixed, then the mixture and the main drug were mixed by method of increment by equal quantity, then prescribed amounts of glidant and lubricant were added, mixed uniformity then tabletting.

EXAMPLE 5

[0116]

TABLE-US-00008 Apremilast Crystalline Form II 15.0 g Lactose 60.0 g micro crystalline cellulose 62.0 g croscarmellose sodium  8.0 g aerosil  2.0 g magnesium stearate  1.0 g

[0117] The main drug was passed through passed through a 200 mesh screen, the filler and disintegrating agent were passed through a 80 mesh screen; prescribed amounts of filler and disintegrating agent were weighted and mixed, then the mixture and the main drug were mixed by method of increment by equal quantity, then prescribed amounts of glidant and lubricant were added, mixed uniformity then tabletting.

EXAMPLE 6

Thermodynamical Stability Studies of Form II and Form B

[0118] Apremilast Crystalline Form II and Form B were suspended in water, respectively, stirred at 60-100° C. for 48 h sampled at a certain time interval and filtered, dried to determine the change of melting temperature; sampled at 24 h, 48 h, filtered and dried to determine change of XRPD patterns, DSC patterns, melting temperature, electrostatic effects, and related substances.

EXAMPLE 7

Apremilast Crystalline Form B Conversion Study

[0119] Apremilast Crystalline Form B (5.0 g, particle size less than 300 mesh) was suspended in 60 ml acetone/water (1:3), heated to refluxing temperature and stirred for 36 h, then cooled while stirring, filtered, dried at 60° C. to obtain about 4.88 g of Apremilast Crystalline Form II, mp:148.3-150.3° C.

[0120] XRPD pattern and DSC pattern demonstrated complete conversion to Form II.

EXAMPLE 8

Apremilast Crystalline Form D Conversion Study

[0121] Apremilast Crystalline Form D (5.0 g, particle size less than 200mesh) was suspended in 60m1 acetone/water (1:3), heated to refluxing temperature and stirred for 8-10 h, then cooled while stirring, filtered, dried at 60° C. to obtain about 4.60 g of Apremilast Crystalline Form II, mp:148.3-150.5° C.

[0122] XRPD pattern and DSC pattern demonstrated complete conversion to Form II.

EXAMPLE 9

in vivo Pharmacokinetic Comparison Study of Apremilast Crystalline Form B and Form II in SD Rats

[0123] 1. Control of Particle Sizes of the Crystals

[0124] The particle sizes of the two forms are controlled by micronization (see below):

TABLE-US-00009 D 0.1 D 0.5 D 0.9 Apremilast Crystalline Form B 1.052 um 6.792 um 55.073 um (APST-B) Apremilast Crystalline Form II 1.395 um 8.722 um 58.942 um (APST-II)

[0125] 2. Method:

[0126] Twelve SD rats weight 200-220 g with half males and half females were divided randomly into 2 groups (named as group A and group B).

TABLE-US-00010 Animal No. El~3 E4~6 F1~3 F4~6 Gender ♂ ♀ ♂ ♀ Form APST-B APST-II

[0127] According to the administration route and dosage amounts provided in FDA references, the two crystalline forms were given by gavage to investigate their pharmacokinetic behaviors in rats. The dosage amounts of the two forms are both 10 mg/kg (solvent is 1% carboxymethylcellulose). The rats were fasted for 12 hs before the study, food was provided 4 hs after administration, water deprivation was not required during the whole study. [0128] Blood was collected via the fundus venous plexus 10, 30mins, 1, 2, 4, 6, 8, 10, 12 and 24 hs after administration. The collected blood was placed on ice and centrifuged for 5min at 8000 rpm, plasma was separated, and cryoperserved in a −20° C. refrigerator. LC-MS/MS was used to determine the concentration of APST in plasma. Linearity range of APST in plasma is 2-1000ng/ml, the linearity was good.

[0129] 3. Experimental Results

[0130] Plasma concentration vs. time plots of rats gavaged with 10 mg/kg APST-B and APST-II suspensions, respectively, were shown in FIGS. 19-22.

[0131] 4. Result Analysis

[0132] The major pharmacokinetic parameters of APST in rats gavaged with 10 mg/kg APST-B and APST-II suspensions, respectively; are shown below: time to peak T.sub.max were 1.6 h (median 2.5 hs) and 1-6 h (median 3 hs); peak concentrations C.sub.max were, respectively, 523.05±417.46 and 506.90±451.89 ng/ml, plasma concentration vs. time plots area under the curve AUC.sub.0-t were, respectively, 3766.48±3617.82 and 5533.11±5613.02 ng.Math.h/ml, the exposure of 10 mg/kg APST-B in rats was about 68.07% of the exposure of APST-II, the difference between the two groups was quite large, and the difference of exposure between females and males were very large, the difference of the exposure between the two groups was not statistically significant due to the large standard deviation. Thus, the pharmacokinetics in females and males were analyzed separately below.

[0133] The major pharmacokinetic parameters of APST in male rats gavaged with 10 mg/kg APST-B and APST-II suspensions, respectively, are shown below: time to peak T.sub.max were 1 h (median 1 h) and 1-2 h (median 1 h); peak concentrations C.sub.max were, respectively, 142.4±13.96 and 107.63±16.05 ng/ml, plasma concentration vs. time plots area under the curve AUC.sub.0-t were, respectively, 530.44±70.05 and 445.59±81.25 ng.Math.h/ml, the C.sub.max and AUC.sub.0-t of 10 mg/kg APST-B in male rats were about 132.3% and 119.0%, respectively, of those of APST-II; the results showed that the absorption of APST-B in male rats was better than APST-II, but the difference was not statistically significant.

[0134] The major pharmacokinetic parameters of APST in female rats gavaged with 10 mg/kg APST-B and APST-II suspensions, respectively, are shown below: time to peak T.sub.max were 2-6 h (median 4 h) and 4-6 h (median 6 h); peak concentrations C.sub.max were, respectively, 903.7±28.47 and 906.17±178.89ng/ml, plasma concentration vs. time plots area under the curve AUC.sub.0-t were, respectively, 7002.52±1140.54 and 10620.62±1053.56 ng.Math.h/ml, the AUC.sub.0-t of 10 mg/kg APST-B in female rats was 65.9% of that of APST-II; the results showed that the absorption of APST-B in female was lower than APST-II, and the difference was statistically significant (P<0.05).

EXAMPLE 10

Study on Comparison of Pharmacokinetics Study of Apremilast Crystal Form B and Apremilast Crystal Form II in Beagle Dogs

[0135] 1. Particle size control of crystal form

[0136] Same as example 9.

[0137] 2. Method

[0138] 6 healthy Beagle dogs weight 6-8 kg with half males and half females were divided randomly into 2 groups, each group having 3.

[0139] According to the administration route and dosage amounts, medicine is administrated orally and the dosage is 30 mg/dog/time. After crude drug powder of two crystal forms being weighed about 30 mg respectively, capsule shell is used to be filled and 10 ml water is used accompanied with administration. The Beagle dogs were fasted for 12 hours before the study, and food is provided in 4 hours after administration. Water deprivation was not required during the whole study. Specific administration groups are designed in the table as below.

TABLE-US-00011 Animal number 1 2 3 4 5 6 Gender ♂ ♀ ♂ ♀ ♂ ♀ Animal group A B First Cycle Dog 1-1 1-2 1-3 1-4 1-5 1-6 number Capsule APST-B APST-II

[0140] 0.5ml venous blood was collected via the small saphenous veins 10, 30 min, 1, 2, 4, 6, 8, 10, 12, 24, 48 and 72 h before (0 hour) or after administration. After centrifugation for 5 minutes at 8000 rpm, blood plasma is separated out and placed in anti freezing plastic test tube for storing in refrigerator at −20 C temporarily.

[0141] Concentration of APST in blood plasma is tested by LC-MS/MS method. The linearity range of APST testing is 5 to 5000 ng/ml, and the linear is good.

[0142] 3. Experiment results [0143] After Beagle dogs being given 30 mg/kg APST-B and APST-II crude drug powder capsule orally respectively, the plasma concentration-time curves are shown in FIG. 23.

[0144] 4. Analysis of results

[0145] Main pharmacokinetic parameters after the Beagle dogs being administrated orally of 30 mg/kg APST-B and APST-II crude drug powder capsules respectively are:

TABLE-US-00012 APST-B APST-II Tmax 1.7 ± 0.6  9.0 ± 13.0 Cmax 2405.7 ± 376.6  2050.7 ± 356.7  AUC.sub.0-t 38032.5 ± 20537.2 37712.7 ± 22408.7 AUC.sub.0-∞ 38497.8 ± 20537.2 38210.7 ± 13015.9

[0146] A t test is carried out after a logarithmic conversion of pharmacokinetic parameters C.sub.max and AUC .sub.0-t. There is no significant meaning (p>0.05) in difference of APST-B and APST-II (p>0.05).