The trial is designed to assess the safety and efficacy of the next-generation WATCHMAN FLX LAAC device to treat patients with NVAF

Laac device

WATCHMAN FLX LAAC device received FDA approval in July 2020. (Credit: Boston Scientific Corporation)

Boston Scientific announced that its next-generation WATCHMAN FLX left atrial appendage closure (LAAC) device has achieved the 24-month endpoint in the PINNACLE FLX clinical study.

The clinical trial is designed to assess the safety and efficacy of the WATCHMAN FLX LAAC device to treat patients with non-valvular atrial fibrillation (NVAF).

Boston’s study assessed the device as an alternative to long-term oral anticoagulation therapy, including non-vitamin K antagonist oral anticoagulants (NOACs), for stroke risk reduction in patients with NVAF.

The company has enrolled 400 patients with NVAF in the prospective and non-randomised trial in the US.

The recruited patients were eligible for anti-coagulation therapy to minimise the risk of stroke but had appropriate rationale to seek a non-pharmaceutical alternative.

The trial has achieved its secondary effectiveness endpoint, which is determined as the occurrence of ischemic stroke or systemic embolism over 24 months, with a rate of 3.4% compared to the performance goal of 8.7%.

It followed the positive 12-month results in which the study achieved the primary safety and efficacy endpoints.

The 24 months data also showed that no patients experienced a device embolisation or pericardial effusion requiring cardiac surgery, in addition to the low rate of ischemic stroke.

Boston Scientific global chief medical officer Dr Ian Meredith said: “The final results of this pivotal study underscore how design advancements of the WATCHMAN FLX device – which allow for improved anchoring, a faster, more effective LAA closure and compatibility with more complex anatomies – have translated into a safe, effective and durable option for patients with NVAF at increased risk for stroke and systemic embolism and an appropriate rationale to seek a non-pharmaceutical alternative.”

In July last year, the company secured approval from the US Food and Drug Administration (FDA) for its next-generation WATCHMAN FLX device. In March 2019, the firm secured CE mark approval for the device.

The WATCHMAN FLX device for use in patients with NVAF is also being evaluated in two randomised controlled trials, including the OPTION trial and the CHAMPION-AF clinical trial.

The OPTION trial is designed to compare the WATCHMAN FLX device to oral anticoagulants in patients who also undergo a cardiac ablation procedure, while the CHAMPION-AF trial is studying a broader anticoagulant-eligible patient population to assess the device against NOACs for embolic stroke prevention.