A bioresorbable triblock copolymer according to Formula 1 R-B-A-B-R  (1) wherein A is a hydrophilic polymer, B a hydrophobic polymer and R are end-groups, wherein R is H or a C1-C30 organic moiety and wherein the copolymer is fluid in a temperature range of 0° C. to 37° C. A pharmaceutical composition including the triblock copolymer and at least one therapeutically active agent. The copolymer and pharmaceutical composition can be used for forming a depot in a human or animal body or as medical device.