Patent Application
20120302633
The hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid (6-dimethylamino methyl-2-naphtalenyl) ester, also known as ITF 2357 and having the International Non Proprietary Name (INN) of Givinostat® is an organic compound with immunosuppressive and anti-inflammatory activity, currently undergoing clinical tests for several diseases related to the deacetylase histone inhibitor capacity thereof.
The structure of such molecule is reported below.
U.S. Pat. No. 6,034,096 reports the preparation of (A) while U.S. Pat. No. 7,329,689 indicates the characteristics and the preparation of a monohydrate polymorph form of the compound (A), called polymorph form I.
U.S. Pat. No. 6,034,096, example 12, actually reports the preparation of compound (A) wherein the product is isolated as a white solid having a melting point of 162-165° C. (with decomposition). In U.S. Pat. No. 7,329,689, with reference to U.S. Pat. No. 6,034,096, it is stated that the product obtained according to U.S. Pat. No. 6,034,096 is an anhydrous, amorphous, hygroscopic and deliquescent product, difficult to handle. A novel monohydrate crystalline form of the compound (A), particularly advantageous for industrial use in that it is stable and easier to handle with respect to the anhydrous product described previously, is actually described in U.S. Pat. No. 7,329,689.
A subject of the present invention is a novel polymorph form of the compound (A), and methods for the preparation thereof. The novel crystalline form subject of the present invention shall be indicated from now henceforth as polymorph form II of the compound (A) and it is characterized by the property of having a greater water solubility with respect to the monohydrate described in U.S. Pat. No. 7,329,689, i.e. the polymorph form I of the compound (A).
During the experiments aimed at identifying novel solid forms of the compound (A), the novel crystalline form II of such compound, whose water solubility characteristics are more favourable with respect to the known monohydrate form I, in that the novel form II has greater solubility with respect to form I was surprisingly discovered. Such characteristic of the novel polymorph is particularly interesting given that the water solubility of a compound has an impact on the bioavailability of such compound (see Pharmaceutical Research, Vol. 12, n. 3, 1995, page 413 “correlations between in vitro dissolution and in vivo bioavailability are extensive . . . .”), hence outlining the possibility of administering the compound (A) in a more bioavailable form, increasing the possibilities of using the active ingredient and contributing to diversifying dosages thereof.
As a matter of fact, a comparative experiment between form I of the compound (A) (monohydrate prepared as described in U.S. Pat. No. 7,329,689) and form II of compound (A), subject of the present invention, was carried out.
10 mg of compound (A) in crystalline form I were agitated in 10 ml of a 0.9% sodium chloride solution (isotonic solution) at 37° C. for 24 hours. The concentration of the product in liquid phase was measured at the end.
Table 1 indicates the obtained solubility data.
The indicated data show that the novel form II is 1.47 times more soluble than the known form I.
The crystalline form II of ITF 2357 is characterised by a powder X-ray diffractogram profile (PXRD) as exemplified in
The characteristic peaks that distinguish the aforementioned PXRD, DSC, TGA and FTIR charts, are those indicated below.
Thus, a subject of the present invention is the hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid (6-dimethylamino methyl-2-naphtalenyl) ester in the crystalline form II, characterised by the Powder X-ray diffractogram profile (PXRD) indicated in
Table 2 indicates the data regarding peaks observed in the PXRD diffractogram.
The crystalline form II is characterised by the DSC profile indicated in
The crystalline form II of the hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid (6-dimethylamino methyl-2-naphtalenyl) ester is characterized by the TGA profile indicated in
The crystalline form II of ITF 2357 subject of the present invention may be obtained through various crystallisation techniques. For example, it may be obtained through crystallisation of the amorphous product as obtained in example 12 of U.S. Pat. No. 6,034,096, from solvents such as alcohols, esters, ketones, ethers, amides, aromatic hydrocarbons, aliphatic hydrocarbons, nitriles and/or mixtures thereof. In particular C1-C6 alcohol solvents, C1-C6 alkyl esters of C1-C6 carboxylic acids are preferred. Even more in particular, the form II is obtained through crystallisation of ITF 2357 from methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-methoxyethanol, isobutanol and mixtures of methanol with esters such as methyl formate, ethyl acetate, isopropyl acetate, n-propyl acetate, diethyl carbonate and ethyl benzoate, from mixtures of methanol with ethers such as 1,4-dioxane, THF, 1,2-dimethoxyethane, diisopropyl ether and t-butyl-methyl ether, from mixtures of acetone with amides such as dimethylformamide and dimethylacetamide, from a mixture of methanol and benzonitrile, from a mixture of benzyl alcohol with methylcyclohexane, from a mixture of methanol and toluene.
Stability tests were performed on form II of ITF 2357, revealing that such crystalline form is stable. In detail, a sample of form II of ITF 2357 was deposited in a thin layer having a thickness of about 0.5 cm on a Petri dish and placed in an environment with a constant humidity of 75%, at a constant temperature of 40° C. for two weeks. Samples were taken after 2, 7 and 15 days and analysed through Powder X Ray Diffraction (PXRD). The results of such experiments were summarised in
Also the pharmaceutical formulations comprising the hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid (6-dimethylamino methyl-2-naphtalenyl) ester in crystalline form II and a pharmaceutically acceptable excipient and/or adjuvant, form a subject of the present invention where such formulations are preferably solid and even more preferably in form of tablets.
The following examples clarify in detail the conditions used for obtaining form II of ITF 2357, but they shall not be deemed restrictive as regards with the scope of protection of the present invention.
Characterisation of ITF 2357 crystalline form II was carried out through the following spectroscopic techniques, according to the following experimental conditions:
The preparation of ITF 2357 used as starting material in the following examples, may be performed through the methods described in U.S. Pat. No. 6,034,096 or in U.S. Pat. No. 7,329,689.
4.0 g of ITF 2357 are introduced into a 250 ml flask, followed by 80 ml of methanol. The mixture is agitated and heated to reflux until complete dissolution of the solid. The reflux is maintained for 15′, then the mixture is cooled until 25° C., leaving under agitation under such conditions for one hour. Then, the obtained solid is filtered on buchner, washing with 10 ml of methanol. This allows obtaining 3.1 g of moist solid which is dried in a rotary evaporator at 45° C. for one night under vacuum (45 mmHg). 2.1 g of ITF 2357 are obtained in crystalline form II, as confirmed by the PXRD analysis.
4.0 g of ITF 2357 and 180 ml of absolute ethanol are added into a 250 ml flask. The mixture is brought to reflux under agitation, the insoluble still present is filtered at such temperature, washed with ethanol and dried at 45° C. under vacuum (45 mmHg) for 10 hours, obtaining 2.8 g of ITF 2357 in crystalline form II.
4.0 g of ITF 2357 and 40 ml of isopropanol are added into a 250 ml flask. The mixture is kept under agitation at 25° C. for 8 hours, then the resulting solid is filtered and it is washed using 10 ml of isopropanol. The obtained product is dried for 16 hours at 40° C. under vacuum (50 mmHg), obtaining 3.7 g of ITF 2357 in crystalline form II.
5.0 g of ITF 2357 and 70 ml of methanol are added into a 250 ml flask and brought to reflux temperature (65° C.); complete solution is observed at such temperature. 44 ml of acetone are thus added to the solution in about 20 minutes. Precipitation of some crystals is observed. The temperature is brought to 25° C., with formation of an abundant precipitate. It is thus cooled to 5° C. and it is left under agitation under such conditions for 30 minutes. Then, the solid is filtered on buchner, washing it with 10 ml of acetone. 5.4 g of a moist solid, which is dried under vacuum (50 mmHg) at 45° C. for 12 hours are obtained. 4.2 g of ITF 2357 in crystalline form II are thus obtained.
5.0 g of ITF 2357 and 70 ml of methanol are added into a 250 ml flask and brought to the reflux temperature (65° C.); complete solution is observed at such temperature. 14 ml of methyl-t-butyl ether are thus added to the solution in about 10 minutes.
The temperature is brought to 25° C., with formation of an abundant precipitate and it is left under agitation under such conditions for 30 minutes. Then, the solid is filtered on buchner, washing it with 10 ml of methyl-t-butyl ether. 4.9 g of a moist solid, which is dried under vacuum (50 mmHg) at 45° C. for 12 hours, are obtained. 4.5 g of ITF 2357 in crystalline form II are thus obtained.
| Number | Date | Country | Kind |
|---|---|---|---|
| MI2010A000121 | Jan 2010 | IT | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/IB2010/055560 | 12/3/2010 | WO | 00 | 7/27/2012 |
