The present invention comprises compositions, methods and kits for delivering drugs. The invention provides an implantable device for delivery of a pharmaceutical substance to a patient, comprising a core comprising a core polymeric material optionally containing a core pharmaceutical substance, surrounded by a first layer comprising a first-layer pharmaceutical substance and a first-layer polymeric material, optionally surrounded by one or more additional layers comprising an additional pharmaceutical substance and an additional polymeric material, where the core, first, and optional additional polymeric materials may be the same or different, and where the optional core pharmaceutical substance, first-layer pharmaceutical substance, and optional additional pharmaceutical substances are the same or different. Implantation of the device allows a controlled release of drug for an extended period of time. The device may be implanted subcutaneously in an individual in need of continuous treatment with a drug.
