In one aspect, the invention provides an implantable device comprising a uniform mixture of components including degradable polymer, inorganic bone particulate either natural or synthetic, a drug, and a soluble microporagen. In some embodiments, the uniform mixture further includes a soluble polymer macroporagen. In some embodiments, the uniform mixture is coated with an immobilized outer porous layer comprising or consisting of synthetic or natural inorganic bone granules. In further aspects, the invention provides an implantable device comprising a composite core of degradable polymer, bone, and a drug, and a coating comprising or consisting of microporous bone overlayer covering the degradable composite core.