INTRACORONARY CU62 RADIATION THERAPY FOR RESTENOSIS

DESCRIPTION: Percutaneous transluminal coronary angioplasty (PTCA) has become the predominant treatment for symptomatic coronary atherosclerotic lesions. Despite its prevalent use, this technique continues to be plagued by restenosis rate of 40% with resultant enormous added health care costs and patient morbidity. Radiation therapy applied locally at the site of coronary balloon injury holds great promise to reduce this restenosis rate. All current and proposed techniques of radiation delivery carry significant drawbacks of safety and effectiveness of uniform dose application. This project proposes a unique, novel approach to radiation delivery through utilization of short-lived positron emitting isotope, Cu-62, produced by a generator system. This isotope is delivered into the angioplasty balloon and provides the required radiation with a brief and safe inflation time. Safety issues are addressed through use of a Cu-62 chemical form assuring blood binding in the event of balloon rupture combined with the short 9.7 minute half-life of Cu-62. Use of a balloon provides significant advantages of uniformity of dose delivery and with Cu-62 is completely safe. In Phase I, an automated concentration system was developed which coupled to the Zn-62/Cu-62 generator produced the highly concentrated solution of Cu-62. This concentrator was employed in porcine overstretch injury model of restenosis, which demonstrated the feasibility of safe use of generator produced Cu-62 and also achieved a substantial reduction of neointimal hyperplasia using a delivered dose of 25 Gy. PROPOSED COMMERCIAL APPLICATION: Not Available