The present invention is directed to polymeric materials comprising biodegradable, dioxanone-based copolymers and implantable devices (e.g., drug-delivery stents) formed of such materials. The polymeric materials can also contain at least one additional biocompatible moiety, at least one non-fouling moiety, at least one biobeneficial material, at least one bioactive agent, or a combination thereof. The polymeric materials are designed to improve the mechanical, physical and biological properties of implantable devices formed thereof.