.

Pharmaceutical Business Intelligence

  • Anticipate P&T budget requirements
  • Evaluate market entry opportunities
  • Find generic sources and suppliers
  • Predict branded drug patent expiration

► Plans and Pricing

Upgrade to enjoy subscriber-only features like email alerts and data export. See the Plans and Pricing

DrugPatentWatch Database Preview

Details for Patent: 8,173,801

« Back to Dashboard

Details for Patent: 8,173,801

Title:Processes for the production of polymorphic forms of rifaximin
Abstract: Crystalline polymorphous forms of rifaximin (INN) antibiotic named rifaximin .alpha. and rifaximin .beta., and a poorly crystalline form named rifaximin .gamma., useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization 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 determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled 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)
Filing Date:Mar 04, 2011
Application Number:13/041,346
Claims:1. A process for the production of rifaximin in polymorphic Form .alpha., comprising: dissolving rifaximin in an alcoholic solvent at a temperature between approximately 45.degree. C. and approximately 65.degree. C.; precipitating the rifaximin by adding water to the alcoholic solvent to form a suspension and by lowering the temperature of the suspension to between approximately 0.degree. C. and approximately 50.degree. C.; and drying the rifaximin for a period of time between approximately 2 and approximately 72 hours to form rifaximin in polymorphic Form .alpha., wherein the rifaximin Form .alpha. has a water content of between 3.0%-4.5%, and 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..

2. A process for the production of rifaximin in polymorphic Form .beta., comprising: dissolving rifaximin in an alcoholic solvent at a temperature between approximately 45.degree. C. and approximately 65.degree. C.; precipitating the rifaximin by adding water to the alcoholic solvent to form a suspension and by lowering the temperature of the suspension to between approximately 0.degree. C. and approximately 50.degree. C.; and drying the rifaximin for a period of time between approximately 2 and approximately 72 hours to form rifaximin in polymorphic Form .beta., wherein the rifaximin Form .beta. has a water content of between 4.5%-5.0%, and 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..

3. A process for the production of rifaximin in polymorphic Form .gamma., comprising: dissolving rifaximin in an alcoholic solvent at a temperature between approximately 45.degree. C. and approximately 65.degree. C.; precipitating the rifaximin by adding water to the alcoholic solvent to form a suspension and by lowering the temperature of the suspension to between approximately 0.degree. C. and approximately 50.degree. C.; and drying the rifaximin for a period of time between approximately 2 and approximately 72 hours to form rifaximin in polymorphic Form .gamma., wherein the rifaximin Form .gamma. has a water content of from between 0% to 1%, and 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..

4. The process of claim 1, further comprising washing the rifaximin Form .alpha. with water after precipitating.

5. The process of claim 1, wherein the alcoholic solvent is ethyl alcohol.

6. The process of claim 1, wherein said water added to precipitate the rifaximin is in a weight amount of between approximately 15% and approximately 70% with respect to the weight amount of alcoholic solvent used for the dissolution.

7. The process of claim 1, wherein after the addition of water, the temperature is lowered to between approximately 28.degree. C. and approximately 32.degree. C.

8. The process of claim 1, wherein the suspension is stirred at a temperature between approximately 40.degree. C. and approximately 50.degree. C. for a period of time between approximately 6 hours and approximately 24 hours.

9. The process of claim 1, where the temperature of the suspension is lowered to approximately 0.degree. C. for a period of time between approximately 15 minutes and approximately one hour.

10. The process of claim 2, wherein the alcoholic solvent is ethyl alcohol.

11. The process of claim 2, wherein after the addition of water, the temperature is lowered to between approximately 28.degree. C. and approximately 32.degree. C.

12. The process of claim 2, wherein the suspension is stirred at a temperature between approximately 40.degree. C. and approximately 50.degree. C. for a period of time between approximately 6 hours and approximately 24 hours.

13. The process of claim 2, where the temperature of the suspension is lowered to approximately 0.degree. C. for a period of time between approximately 15 minutes and approximately one hour.

14. The process of claim 3, further comprising washing the rifaximin Form .gamma. with water after precipitating prior to drying.

15. The process of claim 3, wherein the alcoholic solvent is ethyl alcohol.

16. The process of claim 3, wherein said water added to precipitate the rifaximin is in a weight amount of between approximately 15% and approximately 70% with respect to the weight amount of alcoholic solvent used for the dissolution.

17. The process of claim 3, wherein after the addition of water, the temperature is lowered to between approximately 28.degree. C. and approximately 32.degree. C.

18. The process of claim 3, wherein the suspension is stirred at a temperature between approximately 40.degree. C. and approximately 50.degree. C. for a period of time between approximately 6 hours and approximately 24 hours.

19. The process of claim 3, where the temperature of the suspension is lowered to approximately 0.degree. C. for a period of time between approximately 15 minutes and approximately one hour.
« Back to Dashboard

For more information try a trial or see the database preview and plans and pricing

How are People Using DrugPatentWatch?

Drugs may be covered by multiple patents or regulatory protections. All trademarks and applicant names are the property of their respective owners or licensors. Although great care is taken in the proper and correct provision of this service, thinkBiotech LLC does not accept any responsibility for possible consequences of errors or omissions in the provided data. The data presented herein is for information purposes only. There is no warranty that the data contained herein is error free. thinkBiotech performs no independent verifification of facts as provided by public sources nor are attempts made to provide legal or investing advice. Any reliance on data provided herein is done solely at the discretion of the user. Users of this service are advised to seek professional advice and independent confirmation before considering acting on any of the provided information. thinkBiotech LLC reserves the right to amend, extend or withdraw any part or all of the offered service without notice.

`abc