.

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

Claims for Patent: 6,824,822

« Back to Dashboard

Claims for Patent: 6,824,822

Title: Residual solvent extraction method and microparticles produced thereby
Abstract:Methods for preparing microparticles having reduced residual solvent levels. Microparticles are contacted with a non-aqueous washing system to reduce the level of residual solvent in the microparticles. Preferred non-aqueous washing systems include 100% ethanol and a blend of ethanol and heptane. A solvent blend of a hardening solvent and a washing solvent can be used to harden and wash microparticles in a single step, thereby eliminating the need for a post-hardening wash step.
Inventor(s): Rickey; Michael E. (Loveland, OH), Ramstack; J. Michael (Lebanon, OH), Kumar; Rajesh (Loveland, OH)
Assignee: Alkermes Controlled Therapeutics Inc. II (Cambridge, MA)
Application Number:09/942,631
Patent Claims: 1. A method for preparing microparticles, comprising: preparing an emulsion comprising an active agent and a biodegradable, biocompatible polymer dissolved in a solvent; combining the emulsion with a coacervating agent that is free from solvents for the polymer to form a combined phase; and extracting the solvent from the combined phase with a solvent blend of a hardening solvent and a washing solvent, to thereby form hardened microparticles.

2. The method of claim 1, further comprising after the extracting step: rinsing the microparticles with the hardening solvent.

3. The method of claim 1, wherein the hardening solvent is a liquid alkane.

4. The method of claim 1, wherein the washing solvent is an alcohol.

5. The method of claim 3, wherein the washing solvent is an alcohol.

6. The method of claim 1, wherein the hardening solvent is selected from the group consisting of heptane, hexane, cyclohexane, diethyl ether, petroleum ether, mineral oil, fatty acid esters, and caprylate triglyceride.

7. The method of claim 1, wherein the washing solvent is selected from the group consisting of ethanol and isopropanol.

8. The method of claim 1, wherein the hardening solvent is heptane and the washing solvent is ethanol.

9. The method of claim 1, wherein the solvent is a halogenated solvent.

10. The method of claim 1, wherein the coacervating agent is silicone oil.

11. The method of claim 2, wherein the hardening solvent is heptane.

12. The method of claim 8, further comprising after the extracting step: rinsing the microparticles with heptane.

13. The method of claim 1, further comprising after the extracting step: rinsing the microparticles with a second hardening solvent different from the hardening solvent.

14. Microparticles prepared by the method of claim 1.
« Back to Dashboard

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

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