Polymorphic form of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodophenylamino)-benzamide

1. A crystalline form of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide, wherein the crystalline form is a substantially pure polymorph of Form IV.

2. The crystalline form of claim 1 , wherein the crystalline form has a powder X-ray diffraction pattern comprising peaks at diffraction angles (2θ) of about 4.6, 7.2, 14.6, 19.9, 23.2 and 26.5.

3. The crystalline form of claim 1 , wherein the crystalline form has a powder X-ray diffraction pattern comprising peaks at diffraction angles (2θ) essentially the same as shown in FIG. 1 .

4. A solid form of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide, wherein the solid form comprises Form IV and at least one of polymorphs of Forms I and II.

5. A process for making a polymorph Form IV of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide, the process comprising the steps of:

a) providing an amount of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide into a volume of a C 1 –C 4 lower alkanol and water, the amount of the C 1 –C 4 lower alkanol to water being at a ratio of from about 1:7 to about 1:13, at a temperature of from about 30° C. to about 40° C., to create a mixture of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide in the C 1 –C 4 lower alkanol and water;

b) cooling the mixture of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide in the C 1 –C 4 lower alkanol and water to a temperature from about 20° C. to less than about 30° C.; and

c) separating the polymorph Form IV of N-(R)-2,3-dihydroxy-propoxyl-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide from the C 1 –C 4 lower alkanol and water.

6. The process of claim 5 , wherein the C 1 –C 4 lower alkanol is ethanol.

7. A pharmaceutical composition comprising the crystalline form of claim 1 .

8. A dosage form comprising a pharmaceutically effective amount of the crystalline form of claim 1 and a pharmaceutically acceptable carrier.

9. A method of treating a mammalian disease condition mediated by MEK activity, the method comprising administering to a mammal in need thereof a therapeutically effective amount of the pharmaceutical composition of claim 7 .

10. The dosage form of claim 8 , wherein the amount of Form IV of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide, is from 0.1 to 50 mg.

11. The dosage form of claim 8 , wherein the amount of Form IV of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide, is from 1 to 20 mg.

12. The dosage form of claim 8 , wherein the dosage form is an oral dosage form.

13. The dosage form of claim 12 , wherein the dosage form is a tablet or a capsule.

14. The dosage form of claim 13 , wherein the capsule comprises from 0.1 to 20% of of Form IV of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide, from 75 to 95% of a diluent, and from 3 to 7% of a disintegrant.

15. The dosage form of claim 14 , wherein the capsule further comprises from 0.1 to 2% of a lubricant.

16. The dosage form of claim 15 , wherein the diluent is microcrystalline cellulose, the disintegrant is croscarmellose sodium, and the lubricant is stearic acid or magnesium stearate.

17. The process of claim 5 , wherein N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide is prepared by a method comprising:

a) coupling o-{[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]methyl}hydroxylamine with 3,4-difluoro-2-(2-fluoro-4-iodophenylamino)-benzoic acid using 1,1-carbonyldiimidazole to form N-{[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]methoxy}-3,4-difluoro-2-[(2-fluoro-4-iodophenyl)amino]benzamide; and

b) deprotecting N-{[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]methoxy}-3,4-difluoro-2-[(2-fluoro-4-iodophenyl)amino]benzamide to produce N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide.

18. The process of claim 17 , wherein the method for preparing N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide, further comprises a step of recrystallizing of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino) benzamide.

19. The process of claim 18 , wherein recrystallizing of N-[(R)-2,3-dihydroxy-propoxy]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-benzamide, is carried out in a mixture of toluene, ethanol and water.