The OPTION global trial compared Watchman FLX, a left atrial appendage closure (LAAC) device, to first-line oral anticoagulation (OAC) – including direct oral anticoagulants (DOAC) (95%) and warfarin (5%) – for stroke risk reduction in patients with non-valvular atrial fibrillation following a cardiac ablation. Investigators presented results at the American Heart Association’s Scientific Sessions 2024. They simultaneously published findings in The New England Journal of Medicine.
Boston Scientific said the trial met its primary safety endpoint of non-procedural major bleeding or clinically relevant non-major bleeding at 36 months. Watchman FLX demonstrated superiority to OAC. It also met the primary efficacy endpoint of all-cause death, stroke or systemic embolism at 36 months. Data demonstrated the non-inferiority of Watchman FLX compared to OAC as well.
Additional findings included non-inferiority of Watchman FLX for the combined secondary endpoint of procedural and non-procedural major bleeding at 36 months.
“The OPTION trial data provide clinical evidence indicating that, among patients who have undergone an ablation, LAAC with the Watchman FLX device is not only as safe, but superior to OAC therapy for reducing the risk of long-term bleeding events,” said Dr. Oussama Wazni, vice chair of Cardiovascular Medicine and section head, Cardiac Electrophysiology, Cleveland Clinic, and principal investigator of the OPTION trial. “Notably, we found high rates of procedural success in patients who had a Watchman FLX implant after an ablation, and of patient adherence to their prescribed medication regimen following the procedures, which likely reinforced positive outcomes such as the low rates of ischemic and hemorrhagic stroke within the trial population.”
More info on the Boston Scientific trial
The randomized, controlled OPTION trial included 1,600 patients across 114 sites in the U.S., Europe and Australia.
Boston Scientific reported high rates of procedural success. In the study, approximately 60% of device patients had their Watchman FLX implant 90-180 days following their ablation procedure. The other nearly 40% had the two procedures performed concomitantly, with Watchman FLX coming after ablation.
Watchman FLX produced 8.5% clinically relevant non-major bleeding, compared to 18.1% in the OAC arm. For the primary efficacy endpoint of all-cause death, stroke or systemic embolism, the rate came in at 5.4%. OAC came in at 5.8%, highlighting non-inferiority. Procedural and non-procedural major bleeding rates were 3.9% for Watchman FLX and 5% for OAC.
“The OPTION trial is the first large, randomized trial to rigorously evaluate LAAC as a safe and effective stroke risk reduction treatment following a cardiac ablation in a head-to-head fashion against commonly used oral anticoagulants, including DOAC,” said Brad Sutton, M.D., chief medical officer, Atrial Fibrillation Solutions, Boston Scientific. “These positive primary outcomes mean that patients receiving the WATCHMAN FLX device were able to eliminate long-term medication use while maintaining stroke protection. With this data, we see potential to both expand the indication for the WATCHMAN FLX platform and ultimately elevate it to become a frontline therapy for patients receiving cardiac ablation for atrial fibrillation to reduce their risk of stroke.”
Boston Scientific also has the CHAMPION-AF randomized trial underway, evaluating Watchman against DOAC as a first-line therapy in lower-risk patients. The company has several clinical trials evaluating the latest-generation Watchman FLX Pro as well, which received FDA approval in September 2023. The SIMPLAAFY randomized trial evaluating Watchman FLX Pro looks at a single-drug alternative to dual anti-platelet therapy as a post-procedural regimen.
The analysts’ view and a look at the LAA space
BTIG analysts Marie Thibault and Sam Eiber say they believe the data supports the use of Watchman in decreasing the risk of long-term bleeding and managing the risk of stroke in post-ablation patients.
They note that Boston Scientific expects an FDA label expansion in the second half of 2025.
This latest development further strengthens Boston Scientific’s foothold in the growing LAA device market. Watchman currently competes against offerings like Abbott’s Amplatzer Amulet.
Medtronic threw its hat in the ring with the launch of its Penditure LAA exclusion system about a year ago. That caused worry among AtriCure investors, as AtriCure develops its own LAAC device — the AtriClip. Conformal Medical is another player in the space, with the company reporting “encouraging” results earlier this year when comparing its CLAAS implant to the Watchman FLX.
Meanwhile, Johnson & Johnson made its own LAA play last year with the $400 million acquisition of Laminar. Laminar’s LAA device aims to completely eliminate the appendage to treat AFib.
