Controlled release of drugs or hormones in biodegradable polymer microspheres
US5417982A · kind A · utility
Inventor
Key dates
| Filing date | Feb 17, 1994 |
| Grant date | May 23, 1995 |
| Priority date | — |
| Expiry date | Feb 17, 2014 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K9/1652
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A controlled release formulation for use with a variety of drugs or hormones are formed in microspherical form. The drug or hormone, e.g. bovine somatropine, is suspended in a polymer matrix. The polymer matrix is formed from at least two highly water soluble biodegradable polymers, selected for example from starch, crosslinked starch, ficoll, polysucrose, polyvinyl alcohol, gelatine, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl-ethyl cellulose, hydroxypropyl-methyl cellulose, sodium carboxymethyl cellulose, cellulose acetate, sodium alginate, polymaleic anhydride esters, polyortho esters, polyethyleneimine, polyethylene glycol, methoxypolyethylene glycol, ethoxypolyethylene glycol, polyethylene oxide,poly(1,3 bis(p-carboxyphenoxy) propane-co-sebacic anhydride, N,N-diethylaminoacetate, block copolymers of polyoxyethylene and polyoxypropylene. The microspheres are coated with a (d,1 lactide-glycolide) copolymer. The coating makes the microspheres more resistant to enzymatic degradation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.