A formulation containing a biologically active compound having a chemical structure with hydrogen bonding sites, a first biocompatible, hydrolytically degrading polycarbonate with hydrogen bonding sites and tyrosine-derived diphenol monomer units, and a second biocompatible hydrolytically degrading polymer that is less hydrophobic than the polycarbonate, wherein the second polymer degrades hydrolytically to form acidic degradation products that promote the release of the active compound. Methods for active compound delivery are also disclosed.