LA JOLLA, CA and SEATTLE, WA -- (MARKET WIRE) -- May 17, 2007 -- Celladon Corporation and Targeted Genetics Corporation (NASDAQ: TGEN) today announced the initiation of a Phase I clinical trial of MYDICAR™ (AAV1/SERCA2a) in patients with cardiomyopathy and symptoms of heart failure. MYDICAR™ utilizes an adeno-associated virus (AAV) vector to deliver the SERCA2a gene to heart muscle tissue.