Polymers containing poly(hydroxyalkanoates) and agents for use with medical articles and methods of fabricating the same

#1. Field of the Invention

#This invention is directed to polymers for use with medical articles and, more specifically, polymers containing poly(hydroxyalkanoates) and agents.

#2. Description of the State of the Art

#As discussed in more detail below, embodiments of the present invention generally encompass compositions including a poly(hydroxyalkanoate) (PHA) and an agent such as, for example, a therapeutic, prophylactic, diagnostic and/or other agent, for use with medical articles. The invention also encompasses methods for fabricating the compositions. The medical articles comprise any medical device such as, for example, an implantable medical device such as a stent. In some embodiments, the compositions can be used as a coating on the implantable substrate. In other embodiments, a medical device such as a stent is made in whole or in part from the composition.

#An “agent” can be a moiety that may be bioactive, biobeneficial, diagnostic, plasticizing, or have a combination of these characteristics. A “moiety” can be a functional group composed of at least 1 atom, a bonded residue in a macromolecule, an individual unit in a copolymer or an entire polymeric block. It is to be appreciated that any medical articles that can be improved through the teachings described herein are within the scope of the present invention. Examples of medical devices include, but are not limited to, stents, stent-grafts, vascular grafts, artificial heart valves, foramen ovale closure devices, cerebrospinal fluid shunts, pacemaker electrodes, guidewires, ventricular assist devices, cardiopulmonary bypass circuits, blood oxygenators, coronary shunts (AXIUS™, Guidant Corp.) and endocardial leads (FINELINE® and ENDOTAK®, Guidant Corp.).

#The medical devices can be comprised of a metal or an alloy, including, but not limited to, ELASTINITE® (Guidant Corp.), NITINOL® (Nitinol Devices and Components), stainless steel, tantalum, tantalum-based alloys, nickel-titanium alloy, platinum, platinum-based alloys such as, for example, platinum-iridium alloys, iridium, gold, magnesium, titanium, titanium-based alloys, zirconium-based alloys, alloys comprising cobalt and chromium (ELGILOY®, Elgiloy Specialty Metals, Inc.; MP35N and MP20N, SPS Technologies) or combinations thereof. The tradenames “MP35N” and “MP20N” describe alloys of cobalt, nickel, chromium and molybdenum. The MP35N consists of 35% cobalt, 35% nickel, 20% chromium, and 10% molybdenum. The MP20N consists of 50% cobalt, 20% nickel, 20% chromium, and 10% molybdenum. Medical devices with structural components that are comprised of bioabsorbable polymers or biostable polymers are also included within the scope of the present invention.