Crystalline form of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol

1. A method of decreasing the number of circulating lymphocytes in a subject in need thereof; wherein the method comprises administering a pharmaceutical composition to the subject; wherein the pharmaceutical composition comprises a crystalline form of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)- [1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol, characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 5.4° , 8.5° , and 10.8° ; and wherein the pharmaceutical composition comprises about 2 mg or about 4 mg of the compound.

2. A method according to claim 1 , wherein the pharmaceutical composition comprises about 2 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

3. A method according to claim 1 , wherein the pharmaceutical composition comprises about 4 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

4. A method according to claim 2 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , and 10.8° .

5. A method according to claim 3 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , and 10.8° .

6. A method according to claim 2 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , 10.8° , 12.7° , 14.4° , 17.7° , 20.4° , and 21.3° .

7. A method according to claim 3 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , 10.8° , 12.7° , 14.4° , 17.7° , 20.4° , and 21.3° .

8. A method according to claim 6 , wherein the crystalline form of the compound has a melting point of about 79° C. as determined by differential scanning calorimetry.

9. A method according to claim 7 , wherein the crystalline form of the compound has a melting point of about 79° C. as determined by differential scanning calorimetry.

10. A method according to claim 6 , wherein the pharmaceutical composition comprises 2 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

11. A method according to claim 7 , wherein the pharmaceutical composition comprises 4 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

12. A method of treating a disease or disorder comprising administering a pharmaceutical composition to a subject in need thereof; wherein the pharmaceutical composition comprises a crystalline form of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol, characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 5.4° , 8.5° , and 10.8° ; wherein the pharmaceutical composition comprises about 2 mg or about 4 mg of the compound; and wherein the disease or disorder is selected from the group consisting of rejection of transplanted organs selected from kidney, liver, heart, lung, pancreas, cornea, and skin; graft-versus-host disease; autoimmune syndromes selected from Sjogren's syndrome, spondylarthropathy/ankylosing spondylitis, juvenile arthritis, lupus nephritis, systemic sclerosis, diffuse cutaneous systemic sclerosis, vasculitis, giant cell arteritis, Behcet disease, non-infectious uveitis, Goodpasture syndrome, primary biliary cirrhosis, autoimmune hepatitis, vitiligo, alopecia areata, Rasmussen's encephalitis, rheumatoid arthritis, multiple sclerosis, Crohn's disease, ulcerative colitis, and psoriasis; atopic dermatitis; and type I diabetes.

13. A method according to claim 12 , wherein the pharmaceutical composition comprises about 2 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

14. A method according to claim 12 , wherein the pharmaceutical composition comprises about 4 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

15. A method according to claim 13 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , and 10.8° .

16. A method according to claim 14 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , and 10.8° .

17. A method according to claim 13 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , 10.8° , 12.7° , 14.4° , 17.7° , 20.4° , and 21.3° .

18. A method according to claim 14 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , 10.8° , 12.7° , 14.4° , 17.7° , 20.4° , and 21.3° .

19. A method according to claim 17 , wherein the crystalline form of the compound has a melting point of about 79° C. as determined by differential scanning calorimetry.

20. A method according to claim 18 , wherein the crystalline form of the compound has a melting point of about 79° C. as determined by differential scanning calorimetry.

21. A method according to claim 17 , wherein the pharmaceutical composition comprises 2 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

22. A method according to claim 18 , wherein the pharmaceutical composition comprises 4 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

23. A method of treating systemic lupus erythematosus comprising administering a pharmaceutical composition to a subject in need thereof; wherein the pharmaceutical composition comprises a crystalline form of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol, characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 5.4° , 8.5° , and 10.8° ; and wherein the pharmaceutical composition comprises about 2 mg or about 4 mg of the compound.

24. A method according to claim 23 , wherein the pharmaceutical composition comprises about 2 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

25. A method according to claim 23 , wherein the pharmaceutical composition comprises about 4 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

26. A method according to claim 24 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , and 10.8° .

27. A method according to claim 25 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , and 10.8° .

28. A method according to claim 24 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , 10.8° , 12.7° , 14.4° , 17.7° , 20.4° , and 21.3° .

29. A method according to claim 25 , wherein the crystalline form of the compound is characterised by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 4.2° , 5.4° , 8.0° , 8.5° , 10.8° , 12.7° , 14.4° , 17.7° , 20.4° , and 21.3° .

30. A method according to claim 28 , wherein the crystalline form of the compound has a melting point of about 79° C. as determined by differential scanning calorimetry.

31. A method according to claim 29 , wherein the crystalline form of the compound has a melting point of about 79° C. as determined by differential scanning calorimetry.

32. A method according to claim 28 , wherein the pharmaceutical composition comprises 2 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.

33. A method according to claim 29 , wherein the pharmaceutical composition comprises 4 mg of the compound (S)-3-{4-[5-(2-cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol.