BIOAVAILABLE DOSAGE FORM OF ISOTRETINOIN

摘要

1. A bioavailable capsule formulation of 13-cis vitamin A acid, said formulation comprising: (a) a medicament paste of 13-cis vitamin A acid and a carrier, said acid having a particle size of less than 300 mum; and the surface area of 13-cis vitamin A acid is between 0.05-0.3 m<2>/g, (b) a suspending agent and other pharmaceutical acceptable excipients. 2. The formulation of claim 1 wherein the acid has a particle size of 90% less than about 240 mum and 50% less than about118 mum. 3. The formulation of claim 1 wherein the acid has a particle size of 90% less than about 131 mum and 50% less than about 52 mum. 4. The formulation of claim 1 wherein the particle size of the acid is less than 275 mum. 5. The formulation of claim 1 wherein the carrier is selected from the group consisting of peanut oil, soyabean oil, sesame oil, mineral oil, cotton seed oil and polyethylene glycol. 6. The formulation of claim 1 wherein the suspending agent is a wax mixture comprising 1 part hydrogenated soyabean oil, 1.2 parts white wax and 4.2 parts hydrogenated vegetable oil. 7. The formulation of claim 6 comprising more than 30 weight percent of the suspending agent. 8. The formulation of claim 7 wherein the suspending agent is preferably between 30-40 weight percent. 9. The formulation of claim 1 wherein the dosage form may contain other pharmaceutical acceptable excipients such as cheating agents and anti-oxidants. 10. The formulation of claim 9 wherein the cheating agent is selected from amongst disodium edetate and calcium disodium edetate. 11. The formulation of claim 9 wherein the anti-oxidants are selected from the group consisting a-tocopherols, butylatedhydroxyanisole, butylated hydroxytoluene, ascorbyl palmitate and propyl galate. 12. The formulation of claim 1 wherein the drug in the medicament paste is milled by conventional techniques such as ball mill or colloid mill. 13. A process for the preparation of a bioavailable capsule formulation of 13-cis vitamin A acid comprising the steps of: (a) mixing the acid with the carrier to form a medicament paste; (b) milling the medicament paste to achieve a particle size of said acid of less than 300 mum; and the surface area of 13-cis vitamin A acid is between 0.05-0.3 m<2>/g; (c) mixing the milled medicated paste with a suspending agent and other pharmaceutically acceptable excipients. 14. The process of claim 13 wherein the acid has a particle size of 90% less than about 240 mum and 50% less than about 118 mum. 15. The process of claim 13 wherein the acid has a particle size of 90% less than about 131 mum and 50% less than about 52 mum. 16. The process of claim 13 wherein the particle size of the acid is less than 275 mum. 17. The process of claim 13 wherein the carrier is selected from the group consisting of peanut oil, soyabean oil, sesame oil, mineral oil, cotton seed oil and polyethylene glycol. 18. The process of claim 13 wherein the suspending agent is a wax mixture comprising 1 part hydrogenated soyabean oil, 1.2 parts white wax and 4.2 parts hydrogenated vegetable oil. 19. The process of claim 18 comprising more than 30 weight percent of the suspending agent. 20. The process of claim 19 wherein the suspending agent is preferably between 30-40 weight percent. 21. The process of claim 13 wherein the dosage form may contain other pharmaceutical acceptable excipients such as cheating agents and anti-oxidants. 22. The process of claim 21 wherein the cheating agent is selected from amongst disodium edetate and calcium disodium edetate. 23. The process of claim 13 wherein the anti-oxidants are selected from the group consisting alpha-tocopherols, butylatedhydroxyanisole, butylated hydroxytoluene, ascorbyl palmitate and propyl galate. 24. The process of claim 14 wherein the drug in the medicament paste is milled by conventional techniques such as ball mill or colloid mill.