Biodegradable controlled release systems providing prolonged controlled release of drugs, and methods for the manufacture thereof are disclosed. The systems are formed from a biocompatible, biodegradable polymer, in particular poly-4-hydroxybutyrate (PHA4400) or copolymers thereof. Copolymers of 4-hydroxybutyrate...http://www.google.com.au/patents/US20050025809?utm_source=gb-gplus-sharePatent US20050025809 - Poly-4-hydroxybutyrate matrices for sustained drug delivery
