The FDA Circulatory System Devices Panel Advisory Committee voted 5-3 that benefits of the MitraClip system outweigh the risks for reducing symptomatic mitral regurgitation in high-risk patients.
The panel voted 8-0 that the device was safe, but split on efficacy. In a 5-4 vote, the committee determined that the MitraClip system was not effective. Jeffrey S. Borer, MD, panel chairperson, acted as the tie-breaker for the vote on efficacy.
After the vote, panel member Gregory Dehmer, MD, said, "I will think about this panel for many days to come. …The totality of the data we saw today swayed me to feel like this is a device that has value for a selected group of patients.”
Committee member George W. Vetrovec, MD, said he voted in favor of the efficacy of the device “because the overall risk seemed to be reasonable for this population.”
Despite giving the MitraClip a nod of approval, committee members expressed concern over the quality of the data presented during the meeting.
George W. Vetrovec
"I question all of the data for efficacy," panel member Craig H. Selzman, MD, said. "My overall opinion is that the safety profile is low."
The MitraClip is currently approved for commercial distribution in over 40 countries worldwide.
The EVEREST II randomized controlled trial evaluated the MitraClip (Abbott Vascular) and did not demonstrate an appropriate benefit-risk profile compared with standard mitral valve surgery in a selected mitral valve patient population, according to the FDA Executive Summary.
The summary also highlighted the EVEREST II High Risk Registry (HRR), in which researchers examined 279 patients with grade 3+ to 4+ mitral regurgitation. Patients were randomized 2:1 to either the MitraClip or mitral valve surgery. The effectiveness endpoint was clinical success — defined as freedom from death, mitral regurgitation>2+ and mitral valve reintervention at 12 months — which was met. However, data from the registry are hard to interpret, according to the summary.
Another trial that examined the MitraClip in high-risk patients was the REALISM trial. Patients were considered high surgical risk if their predicted risk of mortality for mitral valve replacement was ≥12%. Study data indicated that there was lower device mortality in the REALISM HRR, 4.0% compared with 7.7% in the EVEREST HRR cohort.
Adverse effects of the MitraClip include allergic reactions, aneurysm, cardiac arrest, dyspnea, edema, fever and hematoma.
Although the FDA is not required to follow the recommendations of the advisory committee, it usually does.
Disclosure: Borer was issued a waiver to allow participation in the meeting; he has an adjunct professor appointment at Cornell University, with which he was previously affiliated on a full-time basis until 2008, which has been identified as a clinical site for the EVEREST II and REALISM studies and will participate in the COAPT study of the device. Vetrovec also was issued a waiver to allow participation in the meeting; he reports owning stockholdings in the sponsoring firm of the premarket approval application under discussion at this meeting and reports owning stock in two firms that make products which would compete with the product that is the subject of discussion. The other committee members declare no relevant financial disclosures related to the advisory committee meeting.