Abstract: Provided herein are 3-dimensional drug-eluting materials comprising biodegradable polymer(s), one or more bioactive agents and entrapped air. Various embodiments of the methods and compositions described herein are based, in part, on the discovery of hydrophobic doping agents that can be used in the manufacture of polymeric drug delivery compositions that permit the encapsulation of air, thereby permitting tunable drug release via controlled air removal. Such compositions are particularly useful for delivering therapeutically effective doses of one or more bioactive agents to a subject over an extended period of time (e.g., days, weeks, or months).