Study of HeartWare Ventricular Assist System in Heart Failure meets primary endpoint-HeartWare

HeartWare International has announced that data from its first destination therapy clinical trial cohort, ENDURANCE, successfully demonstrated that the trial achieved the primary endpoint. HeartWare's ENDURANCE clinical trial is a prospective, randomized, controlled, un-blinded Investigational Device Exemption (IDE) study designed to evaluate the HeartWare Ventricular Assist System as a destination therapy - or long-term therapy - for patients with end-stage heart failure who are ineligible for heart transplantation. Between August 2010 and May 2012, 446 patients were enrolled at 48 U.S. hospital centers and were randomly selected to receive either the HeartWare Ventricular Assist System or, as part of a control group, any alternative Left Ventricular Assist Device (LVAD) approved by the U.S. Food and Drug Administration (FDA) for Destination Therapy, in a 2:1 ratio.

Investigators for the study reported that 55.0% of the investigational device patients attained the primary endpoint of the trial, which is stroke-free survival (Modified Rankin Score ?4) at two years, defined as alive on the originally-implanted device, transplanted or explanted due to patient recovery. In comparison, 57.4% of patients in the control arm achieved the primary endpoint of the study. However, there are concerns over a high rate of stroke amongst patients using the device. Based on these results for the primary endpoint of the ENDURANCE study, non-inferiority of the investigational device was established (p=0.0060). Results from HeartWare's ENDURANCE clinical trial were presented during the Opening Plenary Session at the 35th International Society for Heart and Lung Transplantation (ISHLT) Annual Meeting.

Comment: HeartWare has been dogged by problems: in this new trial, the stroke rate among patients on the device was 31.1%, compared to 12.7% among trial patients implanted with Thoratec's HeartMate II. In addition, in December 2013 the company received reports where the driveline connector locking mechanism has failed to engage as a result of a faulty manufacturing assembly process. This failure could result in the pump stopping and potentially lead to serious adverse health consequences, including death. The FDA instituted a Class I recall. In May 2014, the company has issued a voluntary correction notice about earlier-than-expected battery depletion and routine battery handling in the HeartWare Ventricular Assist System due to a spike in customer complaints. And in June 2014, HeartWare announced that it received a warning letter from the FDA resulting from an inspection of the company's operations, development and manufacturing facility.