Abbott posts positive MitraClip results as FDA looms

Abbott Laboratories' MitraClip demonstrated safe and effective in a new European study.--Courtesy of Abbott Laboratories

After squeaking by an FDA panel in March, Abbott Laboratories' ($ABT) is touting new study results for its MitraClip device, finding it safe and effective for the treatment of mitral regurgitation, a valve disorder that hampers heart function.

In the first study, published in the Journal of the American College of Cardiology, MitraClip lowered the severity of mitral regurgitation in 91.2% of patients with an implant success rate of 99.6% and no incidences of death or stroke. The European study of 567 patients found that 78.9% of those treated with MitraClip experienced only mild mitral regurgitation after one year.

While those results are encouraging, they likely won't distract from the EVEREST II study, announced last month, which found that MitraClip posted almost no clinical benefits over traditional valve surgery after four years. While the effectiveness rates between the device and surgery were not significantly different, one in four MitraClip patients needed a repeat operation in the four-year window, versus just 5.5% of patients who were treated with traditional mitral valve surgery.

Those data reaffirm the FDA's qualms with the device, as agency staff recommended against approving the MitraClip in March, writing that "major questions of safety and effectiveness, as well as the overall benefit-risk profile for this device, remain unanswered" and asking Abbott to come back with more data from its ongoing trials in the U.S. and abroad.

Later that month, the FDA's Circulatory System Devices Panel voted 5-3 that MitraClip's benefits outweighed its risks but split 4-5 over whether it has a reasonable assurance of efficacy in treating mitral regurgitation. Panel recommendations are hardly binding, but the agency takes them into account when deciding whether to approve devices, and Abbott expects to hear a final word from the FDA later this year.

Mitral regurgitation occurs when the mitral valve fails to close all the way, leading to inefficient blood flow that can lead to heart failure. Analysts estimate the worldwide market for transcatheter mitral valve repair could reach $1 billion a year by 2020.

- read the results