Biodegradable, controlled-release microspheres and process for preparing them
US5733567A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 1996 |
| Grant date | Mar 31, 1998 |
| Priority date | — |
| Expiry date | Oct 11, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K9/1647
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Method for the preparation of a pharmaceutical composition in the form of microspheres controllably releasing at least one water-soluble active ingredient. The method comprises the steps of dissolving the active ingredient in a suitable quantity of water, emulsifying the aqueous solution containing the active ingredient with a solution of at least a dl-lactide-co-glycolide-type matrix copolymer in chlorinated hydrocarbon also containing a low molecular weight polyactide release-modulating agent, which results in a first microfine and homogeneous emulsion; emulsifying the first emulsion thus obtained in an external aqueous phase containing a surface active agent; and removing and evaporating the solvent to produce microspheres which are recovered after filtering, washing, and drying. The microspheres themselves.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.