Biodegradable triblock copolymer compositions are provided which are useful in tissue engineering and drug delivery. The copolymers are reverse thermal gels in that when heated from a lower temperature to a higher temperature, they gel. These gels are useful in drug delivery when complexed with an active agent. For example the compositions can be used for intraocular injection of active agents, such as anti-angiogenic agents for treatment of a maculopathy or retinitis.