GB2470378A — A controlled release composition for intraocular delivery of a therapeutic agent

USPTO Abstract

A composition comprises microspheres formed from a polymer which is biodegradable, biocompatible and insoluble in an aqueous solution, wherein the microspheres further include a therapeutic agent. The injectable composition is useful for the intraocular delivery of a pharmaceutical agent, preferably an intravitreal VEGF inhibitor, which provides controlled release of the agent for the treatment of an ocular disorder such as wet macular degeneration. The biodegradable and biocompatible polymer preferably comprises a polyhydroxyalkanoate (PHA) such as poly(3-hydroxyalkanoates), poly(4-hydroxyalkanoates) and copolymers containing a PHA. Preferably each alkanoate unit has from 4 to 16 carbon atoms, for example, polyhydroxyoutanoate, polyhydroxyoctanoate and polyhydroxyvalerate. Copolymers such as poly (3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) may also be employed. The microspheres are preferably uniform in shape and have an average particle size of 0.1 to 10 microns. A process for producing a biodegradable and biocompatible polyhydroxyalkanoate polymer microaphere containing a therapeutic agent and an aqueous product comprising the miccospheres and an aqueous solution are also provided.