Claims for Patent: 8,158,644

Summary for Patent: 8,158,644

Title:	Pharmaceutical compositions comprising polymorphic forms .alpha., .beta., and .gamma. of rifaximin
Abstract:	Crystalline polymorphous forms of rifaximin (INN), referred to as rifaximin .alpha. and rifaximin .beta., and a poorly crystalline form referred to as rifaximin .gamma., useful in the production of medicaments containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a fixed temperature and for a fixed period of time, followed by a drying under controlled conditions until reaching a precise water content in the end product, are the object of the invention.
Inventor(s):	Viscomi; Giuseppe Claudio (Bologna, IT), Campana; Manuela (Bologna, IT), Braga; Dario (Bologna, IT), Confortini; Donatella (Bologna, IT), Cannata; Vincenzo (Bologna, IT), Righi; Paolo (Bologna, IT), Rosini; Goffredo (Bologna, IT)
Assignee:	Alfa Wassermann, S.p.A. (Bologna, IT)
Application Number:	13/041,347
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 8,158,644
Patent Claims:	1. A solid pharmaceutical composition comprising rifaximin in polymorphic Form .alpha. and a pharmaceutically acceptable excipient or carrier, wherein the rifaximin Form .alpha. has x-ray powder diffraction pattern peaks at about 7.4.degree.; 19.7.degree.; 21.0.degree. and 22.1.degree. 2-.theta., wherein the rifaximin Form .alpha. has a water content of between 3.0-4.5%. 2. The pharmaceutical composition of claim 1, wherein the rifaximin Form .alpha. has a water content of 3.0%. 3. The pharmaceutical composition of claim 1, wherein the rifaximin Form .alpha. has a water content of 4.5%. 4. The pharmaceutical composition of claim 1, wherein the excipient is selected from the group consisting of a diluting agent, a binding agent, a lubricating agent, a disintegrating agent, a coloring agent, a flavoring agent, and a sweetening agent. 5. The pharmaceutical composition of claim 1, wherein the composition is for oral use and is in a form selected from the group consisting of coated or uncoated tablets, hard or soft gelatin capsules, sugar-coated pills, lozenges, wafer sheets, pellets, and powders in sealed packet. 6. The pharmaceutical composition of claim 1, wherein the composition further comprises an ingredient selected from the group consisting of colloidal silicon dioxide, hydroxypropyl methylcellulose, cellulose, microcrystalline cellulose, propylene glycol, sodium starch glycolate, talc, and a combination thereof. 7. The pharmaceutical composition of claim 1, further comprising rifaximin in polymorphic Form .beta. having x-ray powder diffraction pattern peaks at about 5.4.degree.; 9.0.degree.; and 20.9.degree. 2-.theta.. 8. The pharmaceutical composition of claim 1, further comprising rifaximin in polymorphic Form .gamma. having x-ray powder diffraction pattern peaks at about 5.0.degree., 7.1.degree., and 8.4.degree. 2-.theta.. 9. A solid pharmaceutical composition comprising rifaximin in polymorphic Form .beta. and a pharmaceutically acceptable excipient or carrier, wherein the rifaximin Form .beta. has x-ray powder diffraction pattern peaks at about 5.4.degree.; 9.0.degree.; and 20.9.degree. 2-.theta. and wherein the rifaximin Form .beta. has a water content of between 4.5%-5.0%. 10. The pharmaceutical composition of claim 9, wherein the rifaximin Form .beta. has a water content of 5.0%. 11. The pharmaceutical composition of claim 9, wherein the excipient is selected from the group consisting of a diluting agent, a binding agent, a lubricating agent, a disintegrating agent, a coloring agent, a flavoring agent, and a sweetening agent. 12. The pharmaceutical composition of claim 9, wherein the composition is for oral use and is in a form selected from the group consisting of coated or uncoated tablets, hard or soft gelatin capsules, sugar-coated pills, lozenges, wafer sheets, pellets, and powders in sealed packet. 13. The pharmaceutical composition of claim 9, wherein the composition further comprises an ingredient selected from the group consisting of colloidal silicon dioxide, hydroxypropyl methylcellulose, cellulose, microcrystalline cellulose, propylene glycol, sodium starch glycolate, talc, and a combination thereof. 14. The pharmaceutical composition of claim 9, further comprising rifaximin in polymorphic Form .gamma. having x-ray powder diffraction pattern peaks at about 5.0.degree., 7.1.degree., and 8.4.degree. 2-.theta.. 15. A solid pharmaceutical composition comprising rifaximin in polymorphic Form .gamma. and a pharmaceutically acceptable excipient or carrier, wherein the rifaximin Form .gamma. has x-ray powder diffraction pattern peaks at about 5.0.degree., 7.1.degree., and 8.4.degree. 2-.theta. and wherein the rifaximin Form .gamma. has a water content of from between 0% to 1%. 16. The pharmaceutical composition of claim 15, wherein the rifaximin Form .gamma. has a water content of 0%. 17. The pharmaceutical composition of claim 15, wherein the rifaximin Form .gamma. has a water content of 1%. 18. The pharmaceutical composition of claim 15, wherein the excipient is selected from the group consisting of a diluting agent, a binding agent, a lubricating agent, a disintegrating agent, a coloring agent, a flavoring agent, and a sweetening agent. 19. The pharmaceutical composition of claim 15, wherein the composition is for oral use and is in a form selected from the group consisting of coated or uncoated tablets, hard or soft gelatin capsules, sugar-coated pills, lozenges, wafer sheets, pellets, and powders in sealed packet. 20. The pharmaceutical composition of claim 15, wherein the composition further comprises an ingredient selected from the group consisting of colloidal silicon dioxide, hydroxypropyl methylcellulose, cellulose, microcrystalline cellulose, propylene glycol, sodium starch glycolate, talc, and a combination thereof.