Near-Term Impact of Boston Scientific's OPTION Results May Be Limited

Boston Scientific, an MD+DI Medtech Company of the Year finalist, announced positive three-year primary endpoint results over the weekend from the OPTION global clinical trial of its Watchman Flx left atrial appendage closure (LAAC) device.

Key findings from the study comparing the 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 were presented in a late-breaking science session at the American Heart Association's Scientific Sessions 2024 and simultaneously published in The New England Journal of Medicine.

The trial met the primary safety endpoint of non-procedural major bleeding or clinically relevant non-major bleeding at 36 months, with the Watchman Flx device demonstrating superiority to OAC (8.5% vs. 18.1%; P<0.0001). It also met the primary efficacy endpoint of all-cause death, stroke, or systemic embolism at 36 months, with the data showing non-inferiority of the device to OAC (5.4% vs. 5.8%; P<0.0001). Additional findings included non-inferiority of the Watchman Flx device for the combined secondary endpoint of procedural and non-procedural major bleeding at 36 months (3.9% vs. 5.0%; P<0.0001).

“We believe these data support the use of Watchman to decrease the risk of long-term bleeding and manage the risk of stroke in post-ablation patients,”  Marie Thibault, a medtech analyst at BTIG, wrote in a report Sunday. She also noted that Boston Scientific has said it expects to receive an FDA label expansion in the second half of 2025.

In recent years, the number of patients with atrial fibrillation who have undergone a cardiac ablation procedure to prevent symptoms has grown significantly, Boston Scientific noted. Due to the risk of atrial fibrillation recurrence following an ablation, current treatment guidelines recommend that patients with multiple stroke risk factors remain on OAC long term to reduce the risk of stroke. However, symptomatic relief can lead these patients to stop taking their blood thinners, increasing this risk, while long-term use of OAC also presents a risk of serious bleeding.

"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 Oussama Wazni, MD, vice chairman of cardiovascular medicine and section head of cardiac electrophysiology at the Cleveland Clinic, and principal investigator of the OPTION trial. Wazni is also a paid consultant of Boston Scientific. "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."

The randomized, controlled OPTION trial included 1,600 patients enrolled across 114 sites in the United States, Europe, and Australia, and demonstrated high rates of procedural success. In the trial, about 60% of device patients had their Watchman Flx implant 90-180 days following their ablation procedure. The other nearly 40% of the device patients had the two procedures performed concomitantly, with the Watchman Flx implant taking place after the ablation.

"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, MD, chief medical officer of atrial fibrillation solutions at 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."

In addition to the OPTION trial, the Watchman technology is being evaluated against DOAC as a first-line therapy in lower-risk patients within the CHAMPION-AF randomized trial. The latest-generation Watchman Flx Pro LAAC device, which FDA approved last year, is similarly being studied in several clinical trials, including the SIMPLAAFY randomized controlled trial that is evaluating a single-drug alternative to dual anti-platelet therapy as a post-procedural regimen.

Will current Medicare NCD limit the benefit of OPTION results?

Mike Matson, a medtech analyst at Needham & Co., wrote that he believes Boston Scientific’s CHAMPION-AF trial will have a “much bigger impact” on Watchman sales than the OPTION trial. He noted in his report Monday morning that Boston Scientific management expects the CHAMPION-AF results to be presented in the first half of 2026.

The analyst does not expect the Medicare left atrial appendage closure National Coverage Determination (NCD) to be revised until after the CHAMPION-AF results and he thinks the current NCD may limit the use of Watchman under the expanded OPTION indication for Medicare patients.

“Overall, we believe that the OPTION results are a positive for [Boston Scientific] and represent another step in [Boston Scientific’s] well-planned longer-term effort to expand the WATCHMAN market, but we expect the nearer-term impact to be limited,” Matson wrote.