Pharmaceutical composition for the treatment of Duchenne muscular dystrophy

1. A liquid pharmaceutical composition comprising an aqueous suspension of nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole, wherein the nanoparticles have a D 50 particle size less than 2 μm and/or a D 90 particle size less than 7 μm.

2. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has a D 50 particle size less than 1.5 μm.

3. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has a D 90 particle size less than 3000 nm.

4. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has a D 90 particle size of about 1800 nm.

5. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has: (a) a D 50 particle size less than 0.6 μm; and/or (b) a D 90 particle size less than 1.8 μm.

6. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has the following particle size distribution (PSD): D 10 <1.2 μm, D 50 <1.8 μm and D 90 <5.4 μm.

7. The composition of claim 1 wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has the following particle size distribution (PSD): D 10 <0.8 μm, D 50 <1.2 μm and D 90 <3.6 μm.

8. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has the following particle size distribution (PSD): D 10 ≦0.4 μm, D 50 : ≦0.6 μm and D 90 ≦1.8 μm.

9. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole is present as a discrete solid-state phase, wherein the solid-state phase is crystalline, semi-crystalline or amorphous form.

10. The composition of claim 9 wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole is present in crystalline form.

11. The composition of claim 10 wherein the crystalline form is polymorph Form I which has an X-ray diffraction pattern as shown in Figure One.

12. The composition of claim 1 , wherein the 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole is present in an amount of 1 to 30 wt %.

13. The composition of claim 1 , wherein the 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole is present in an amount of 1.5 to 20 wt %.

14. The composition of claim 1 , wherein the 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole is present in an amount of 2.0 to 10 wt %.

15. The composition of claim 1 , further comprising at least one pharmaceutically acceptable surfactant.

16. The composition of claim 15 wherein the at least one pharmaceutically acceptable surfactant is present in an amount effective to inhibit agglomeration of the 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole nanoparticles.

17. The composition of claim 15 wherein said at least one pharmaceutically acceptable surfactant is hydroxypropyl methylcellulose or a poloxamer.

18. The composition of claim 17 wherein said at least one pharmaceutically acceptable surfactant comprises hydroxypropyl methylcellulose and a poloxamer.

19. The composition of claim 15 wherein said at least one pharmaceutically acceptable surfactant is present in an amount of 0.5 to 4 wt %.

20. The composition of claim 18 wherein the hydroxypropyl methylcellulose or the poloxamer are present at 0.5 to 2 wt %.

21. The composition of claim 1 further comprising at least one preservative.

22. The composition of claim 21 wherein the preservative comprises at least one paraben.

23. The composition of claim 22 wherein said at least one paraben is methyl paraben or propyl paraben.

24. The composition of claim 23 wherein said at least one paraben comprises methyl paraben and propyl paraben.

25. The composition of claim 24 wherein the methyl paraben is present at up to 0.15 wt % and/or the propyl paraben is present at up to 0.015 wt %.

26. The composition of claim 1 further comprising at least one sweetening agent.

27. The composition of claim 26 wherein said at least one sweetening agent is glycerol or sorbitol.

28. The composition of claim 27 wherein said at least one sweetening agent comprises glycerol and sorbitol.

29. The composition of claim 28 wherein the glycerol is present at at least 5 wt % and/or the sorbitol is present at about 5 wt %.

30. The composition of claim 1 further comprising at least one flavouring agent.

31. The composition of claim 30 wherein said at least one flavouring agent comprises strawberry cream flavour.

32. The composition of claim 1 further comprising a suspension stabilizing agent.

33. The composition of claim 32 wherein the suspension stabilizing agent is xanthan gum.

34. The composition of claim 33 wherein the xantham gum is present at up to 1.0 wt %.

35. The composition of claim 1 , wherein the composition has a pH of 4-8.

36. The composition of claim 1 , wherein the composition is adapted for oral administration.

37. The composition of claim 1 , wherein the composition consists essentially, of: (a) 2-20, 2-10 or about 20 wt % nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole; (b) about 0.15 wt % methyl paraben; (c) about 0.015 wt % propyl paraben; (d) about 1 wt % poloxamer 188; (e) 0-1.0, e.g. about 1 wt % hydroxypropyl methylcellulose; (f) about 0.8 wt % flavouring agent; (g) about 5 wt % glycerol; (h) about 5 wt % 70% non crystallising sorbitol; and (i) 0.25-1.0 wt % xanthan gum; the balance being (k) water.

38. A method for the treatment or prophylaxis of Duchenne muscular dystrophy or Becker muscular dystrophy in a patient in need thereof, comprising orally administering to the patient an effective amount of the composition of claim 1 .

39. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has a D 50 particle size less than 1.0 μm.

40. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has a D 50 particle size less than 0.75 μm.

41. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has: (a) a D 50 particle size of about 0.5 μm; and/or (b) a D 90 particle size of about 1.0 μm.

42. The composition of claim 1 , wherein the nanoparticulate 5-(ethylsulfonyl)-2-(napthalen-2-yl)benzo[d]oxazole has the following particle size distribution (PSD): D 10 is ˜0.4 μm, D 50 is ˜0.6 μm and D 90 is ˜1.8 μm.

43. The composition of claim 17 , wherein said at least one pharmaceutically acceptable surfactant is poloxamer 188.

44. The composition of claim 18 , wherein the poloxamer is poloxamer 188.

45. The composition of claim 25 wherein the methyl paraben is present at about 0.15 wt % and/or the propyl paraben is present at about 0.015 wt %.

46. The composition of claim 27 wherein said at least one sweetening agent is non crystallising sorbitol.

47. The composition claim 35 , wherein the composition has a pH of between 7 and 8.