The present invention relates to a drug delivery device comprising (a) an active compound and (b) a thermo-sensitive polymeric material comprising a copolymer of styrene and C1-C12 alkyl (meth)acrylate, having a barrier effect against diffusion of an active compound and having a glass transition temperature within the range of about 0° to about 90°C wherein the characteristics of diffusion or transport of the active compound can be modified in a reversible manner by supplying energy from an energy source.The invention further relates to a method for releasing an active compound from a drug delivery device, the drug delivery device comprising (a) an active compound and (b) a thermo-sensitive polymeric material comprising a copolymer of styrene and C1-C12 alkyl (meth)acrylate, having a barrier effect against diffusion of an active compound and having a glass transition temperature within the range of about 0° to about 90°C wherein the active compound is released from the drug delivery device by reversibly modifying the transport characteristics of the thermo-sensitive polymeric material by supplying energy from an energy source.
