Thoratec Corporation, a world leader in device-based mechanical circulatory support therapies to save, support and restore failing hearts, has received FDA approval of its PMA (Pre-Market Approval) supplement, allowing the use of its HeartMate II LVAS (Left Ventricular Assist System) for Destination Therapy (DT).
With this approval, the HeartMate II can be used to provide long-term cardiac support for patients suffering from advanced-stage heart failure who are not eligible for transplantation. Thoratec said it will begin the rollout of the device for the DT indication immediately and has sufficient inventory to address the expected increase in demand. The device was approved for Bridge-to-Transplantation (BTT) in the US under the original PMA in April 2008.
The approval allows the HeartMate II to be used in patients with New York Heart Association (NYHA) Class IIIB or IV end-stage left ventricular failure who have received optimal medical therapy for at least 45 of the last 60 days, and who are not candidates for cardiac transplantation. The PMA approval was based on a filing submitted in April 2009 that included two-year data on a pivotal study cohort of 200 randomized patients enrolled at 38 centres. Patients in the HeartMate II DT trial were randomized to the HeartMate II or the HeartMate XVE--the only other device approved for DT--on a 2:1 basis, respectively. Patients in the pivotal cohort ranged in age from 26-81 years old, with a median age of 64 years. Also included in the primary analysis were data on 24 small BSA (body surface area) patients who because of their body size could not be randomized to the larger HeartMate XVE. The filing also included data on adjunctive cohorts totalling an additional 409 patients, including those who had been originally supported by a HeartMate XVE, and based on the need for device replacement, elected to receive a HeartMate II, as well as patients enrolled under Continuous Access Protocols (CAPs).
"This is truly a momentous day for the hundreds of thousands of underserved advanced-stage heart failure patients," noted Gary F. Burbach, president and chief executive officer of Thoratec. "Those who now have access to the device owe a great deal to the patients and clinicians who participated in this landmark trial.
"As the data from both the trial and the BTT commercial experience with the device demonstrate, the HeartMate II is a proven therapy that extends patients' lives while providing them a significantly improved quality of life. We have been laying the groundwork for the DT launch through both our device manufacturing initiatives and market development programmes targeted to clinicians and the 76 centres that have received certification from Centers for Medicare and Medicaid Services (CMS) for DT reimbursement. In addition, this approval will facilitate our initiatives to build upon our already strong presence in Europe," he added.
As a condition of approval, Thoratec has agreed to a post-approval study of 247 patients who will be followed until outcome or two years, whichever occurs first. Thoratec will utilize the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) to collect the FDA-required data on outcomes, adverse events, functional status and quality of life. Thoratec has also agreed to conduct a second small study at three specific centres to collect data regarding the relationship between bleeding, thrombosis, von Willebrand syndrome and anticoagulation in LVAD (Left Ventricular Assist Device) patients.
"Data from the DT trial demonstrated that the HeartMate II achieved statistically superior results over the patients in the control group who were implanted with the HeartMate XVE. The study primary composite endpoint included survival at two years, free of a debilitating stroke and reoperation to repair or replace the device. The HeartMate II also demonstrated substantially improved two-year survival of 58 per cent versus 24 per cent for the XVE patients," Burbach noted. "In addition," he continued, "the improvements in patients' quality of life were dramatic at two years of support, with 80 per cent of the HeartMate II patients achieving Class I or Class II status, compared to zero at baseline. We believe these outcomes are particularly impressive when you consider the status of these patients at the time they entered the trial. They had a similar profile to those in the REMATCH trial who were managed with the standard of care of optimal medical management and experienced a two-year survival rate of eight percent versus the 58 per cent achieved by HeartMate II patients in this trial.
"The data also showed similar outcomes between men and women implanted with the HeartMate II. 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. The trial outcomes also demonstrated superior safety profiles for the HeartMate II, based on its lower level of major adverse events, including reduced rates of infections, 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 noted.
"This approval will only add to the enthusiasm among the clinical community, based on the HeartMate II's experience with BTT patients, and we look forward to facilitating the adoption of this therapy among a wider group of patients. We believe the HeartMate II represents clinically proven technology, and when combined with our new HeartMate peripherals, offers a compelling and economically viable therapy for heart failure patients. Our focus now is to educate the referring cardiologist community about the efficacy of the device and continue to help VAD centres bring on DT programs. Through our training initiatives, support for centres and educational programs targeted to referring cardiologists, we are committed to advancing the field of mechanical circulatory support and improving the outcomes for a much broader population of advanced-stage heart failure patients," Burbach continued.
The HeartMate II and the HeartMate XVE are the only devices 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 previously approved pulsatile devices.