Pharmaceutical composition

A pharmaceutical composition comprising:

• at least one pharmaceutically active ingredient and a biodegradable multi-branched copolymer comprising at least three polyester arms attached to a central core which comprises a polyether, wherein the central core is a multi-branched polyether which is poly(ethylene glycol) (PEG) and a polyol and the polyether is 10 kDa or less, the polyester is or comprises PLA, wherein the PLA is or comprises PDLLA, the multi-branched copolymer having the formula A(B)n wherein A represents the central core, B represents the polyester arms and n is an integer of at least 3, wherein the multi-branched copolymer is substantially insoluble in aqueous solution;
• and
• a biocompatible organic solvent in an amount at least 25% (w/w %) of the total composition.