The approval includes labeling with a 45-day dual anti-platelet therapy (DAPT) option for the left atrial appendage closure device (LAAC). DAPT represents an alternative to 45-day oral anticoagulation (OAC) plus aspirin for post-procedural treatment of non-valvular atrial fibrillation (NVAF) patients.
Dr. Ian Meredith, global CMO for Boston Scientific, said in a news release that the approval represents a significant step forward. “This revised labeling provides physicians more flexibility to exercise their clinical judgment based on individual patient characteristics to determine the most appropriate post-procedural antithrombotic medication regimen.”
Meredith added that the legacy Watchman and current-generation Watchman FLX tech’s robust safety and efficacy profile backed the approval.
Marlborough, Massachusetts–based Boston Scientific submitted clinical evidence, including analyses from approximately 8,300 patients. Data came from the Left Atrial Appendage Occlusion Registry (LAAO Registry) within the American College of Cardiology Foundation’s (ACCF) National Cardiovascular Data Registry (NCDR).
The company submitted data to support the safety and efficacy of DAPT as a post-procedural antithrombotic regimen in patients with NVAF who may have a reason to seek an alternative to OAC. The updated FDA label has been available in Europe since 2017, Boston Scientific said.
More than 17,000 patients from the NCDR-LAAO registry demonstrated no significant difference in rates of major adverse events at 45 days post-implant. This occurred regardless of whether patients were discharged from the hospital on DAPT, a direct OAC and aspirin, or warfarin and aspirin.
Registry data demonstrated only a 0.37% rate of major adverse events at seven days following a Watchman FLX implant or the time of hospital discharge (whichever came later).
More positive studies
In May, Boston Scientific reported in-hospital outcomes for Watchman FLX compared with Watchman 2.5. The outcomes demonstrated a 43% lower rate of in-hospital major adverse events with the newer generation FLX. That included lower rates of pericardial effusion requiring intervention and major bleeding. Major in-hospital major adverse events included a composite of death, cardiac arrest, stroke, transient ischemic attack, intracerebral hemorrhage, systemic embolism, major bleeding, major vascular complication, myocardial infarction, pericardial effusion requiring intervention, and device embolization.
Last year, Boston Scientific announced retrospective study data from 300 Danish patients finding that Watchman FLX demonstrated superiority in the area of LAA closure and peri-device leak compared to Abbott’s Amplatzer Amulet LAAC device.
The company said multiple clinical trials remain ongoing to evaluate Watchman FLX. The Champion-AF and Option clinical trials are evaluating the use of the device for broader patient populations with NVAF.
