Thoratec Corporation (Thoratec), a developer of technologies to treat heart failure, has announced the Destination Therapy (DT) pivotal trial results for the HeartMate II left ventricular assist system (LVAS) demonstrating that the device achieved statistically superior results over the HeartMate XVE, including survival at two years while remaining free from disabling stroke or the need for reoperation to replace or repair the pump.
As treated survival was 58% for HeartMate II patients versus 24% for the HeartMate XVE patients.
The data were presented at a clinical trial session of the 2009 Scientific Sessions of the American Heart Association by Dr. Joseph Rogers of Duke University on behalf of the HeartMate II investigators. The trial data were also published in an article.
The HeartMate II Destination Therapy trial involved 200 patients enrolled at 38 centers who were randomized to the HeartMate XVE on a 2-1 basis, respectively. In the study, 46% of the HeartMate II patients successfully achieved the primary composite endpoint of survival at two years while remaining free from disabling stroke or the need for reoperation to replace or repair the pump versus eleven percent of the XVE patient cohort, on an intent to treat basis. Secondary endpoints in the trial included as treated actuarial survival, adverse events, functional status, patient quality of life, hospitalization and assessment of neuro-cognitive function. Patients enrolled in the trial ranged in age from 26-81 years old, with a median age of 64 years.
“We find the two-year survival data, as well as that related to pump performance, adverse events, quality of life and functional status, to be highly positive. Treating patients with the HeartMate II leads to dramatically improved survival, functional capacity and quality of life beyond any other therapy for advanced-stage heart failure patients. We believe the trial outcomes will drive market adoption of the device once it receives DT approval from the FDA, given the poor outcomes with other treatment options available for these patients,” said Gary F. Burbach, president and chief executive officer of Thoratec.
“The outcomes of this study are particularly impressive when you consider the status of these patients at the time they entered the trial,” Dr. Slaughter noted. “These patients have a similar profile to those in the REMATCH trial who were managed with the standard of care (optimal medical management) and had a two-year survival rate of eight percent versus the 58% achieved by the HeartMate II in this trial,” he added.
“The trial outcomes showed that the smaller size of the HeartMate II enables its use in a broader patient population, including the currently under-served population of small sized patients with advanced-stage heart failure, most notably women. They also demonstrated superior safety profiles for the HeartMate II, based on the level of major adverse events, including reduced rates of infection, renal failure, right heart and respiratory failure and cardiovascular arrhythmia. HeartMate II patients also fared better with respect to shorter hospital stays and lower rates of re-hospitalizations and reoperations per year,” Burbach added.
Burbach noted that at two years of support, 80% of the HeartMate II patients were NYHA Class I or II compared to zero at baseline, and there was a doubling of the distance a patient could walk. Improvements over baseline in the HeartMate II patients were statistically significant in all quality of life and functional measures.
“There is an unmet need among thousands of patients annually with advanced-stage heart failure who are ineligible for cardiac transplantation and do not benefit from medical therapy. For these patients with limited treatment options, the HeartMate II is a therapy that can provide long-term hemodynamic support that is also linked to significant improvements in longevity and quality of life,” Dr. Rogers said.
The HeartMate II was approved for Bridge-to-Transplantation (BTT) in the US in April 2008, and the HeartMate XVE is the only device approved by the FDA for both DT and BTT. A continuous flow device, the HeartMate II is an implantable LVAS powered by a rotary pumping mechanism and is designed to have a much longer functional life than pulsatile devices and to operate more simply and quietly. The device provides blood flow through the circulatory system on a continuous basis with only one moving part. It is also smaller and easier to implant than a pulsatile device.