Atritech said that in a recent letter the agency has requested that a confirmatory study be conducted to further substantiate the safety and effectiveness of the Watchman LAA Closure Technology in patients with atrial fibrillation at risk of stroke and eligible for anticoagulation therapy. The company will be working closely with the FDA to finalize the study design and is looking to start the confirmatory study later this year.

Reportedly, David Holmes, president-elect of American College of Cardiology (ACC) has presented 1350 patient years of follow up data from the Protect AF clinical trial at the annual ACC meeting in Atlanta. The study data include a 31% risk reduction in all stroke, cardiovascular death and systemic thromboembolism in the Watchman group as compared to patients on Warfarin. The results presented were comparable to those presented in the initial data published in the Lancet, August 2009.

The Protect AF clinical trial has evaluated the Watchman LAA Closure Device versus the current standard of care, Warfarin, in patients with non-valvular atrial fibrillation. The trial enrolled a total of 800 patients and now has an average follow up of two years. Protect AF is the prospective, randomized clinical trial comparing an LAA closure device to long term Warfarin therapy. In August 2008, the company began enrolling patients in a Continued Access Study in the US and has over 420 patients implanted.

Jim Bullock, president and CEO of Atritech, said: “The adoption of the Watchman technology in markets outside of the US has been largely due to the compelling data contained in the Protect AF clinical trial. The initiation of a confirmatory study combined with the continued follow up of our study patients will further establish the clinical significance of this important technology.”