Overexpression of AC6 preserved heart function in a genetic model of cardiomyopathy.465,466 The beneficial effect of AC6 is likely to be mediated by a cAMP-independent mechanism, such as improving Ca2+ mishandling.467,468 Therefore, a phase 2 study was designed to test the safety and efficacy of single intracoronary administration of Ad5 encoding human AC6 (Ad5.hAC6). The gene discussed is ADCY6; the disease is cardiomyopathy.