- A closely watched clinical trial of Boston Scientific’s pulsed field ablation (PFA) device has met its primary endpoint. Boston Scientific published the data in The New England Journal of Medicine.
- The ADVENT study found Boston Scientific’s Farapulse is as safe and effective as the standard of care in atrial fibrillation, although BTIG analysts said a death in the PFA arm may “distract from overall safety.”
- Despite that concern, analysts at BTIG and other companies were enthusiastic about the results, with the team at RBC Capital Markets forecasting “conversion of 80% to 90% of the market over a 2-3 year period.”
PFA is a minimally invasive procedure that uses electrical pulses to scar heart tissue, preventing atrial fibrillation.
Boston Scientific has subjected Farapulse to a more rigorous clinical development program than its main PFA rivals Johnson & Johnson and Medtronic, who ran single-arm studies, according to BTIG analysts. Unlike its rivals, Boston Scientific compared its device to standard of care radiofrequency or cryoballoon ablation. The approach has delivered data that show PFA is at least a match for existing AFib treatments and could drive the transformation of electrophysiology.
“With PFA offering a faster ablation approach that is at least as effective and safe as the standard of care even though operators had little experience with the new technology, we expect U.S. electrophysiologists will adopt PFA as enthusiastically as their peers in Europe,” the BTIG analysts wrote in a note to investors.
Investigators randomized more than 600 people to undergo PFA or thermal ablation. Off-drug treatment success after 12 months was 73% in the PFA arm and 71% in the thermal arm, showing Farapulse is non-inferior, but not statistically superior, to the standard of care.
The hit on the non-inferiority primary endpoint and miss on the superiority secondary endpoint largely matched analyst expectations, although the team at J.P. Morgan highlighted the numerical advantage of the PFA arm as a positive surprise. The study also found PFA procedure times were significantly shorter and less variable than thermal ablation procedures.
On the safety front, investigators reported six adverse events in the PFA cohort and four adverse events in the control group. That topline safety finding hides a mix of positives and negatives for Farapulse.
The main negative is that one patient in the Farapulse arm died. Analysts at Truist spoke to two key opinion leaders about the death. Neither expert was concerned because the event was “not device related/specific.” The experts also cited the “extensive experience with Farapulse in Europe” as evidence of the safety of the device.
The main positive in the safety data is the rate of post-ablation narrowing of the pulmonary veins at three months. The rate in the PFA arm was 0.9%, compared to 12% in the thermal ablation cohort.
Analysts at RBC and Stifel noted the potential for the results to get better as operators gain more experience with the technology. Boston Scientific is analyzing whether outcomes improved as physicians gained experience using Farapulse throughout the course of the trial, according to the Stifel analysts.
Even without improvements, analysts think PFA is capable of disrupting the electrophysiology market. Abbott, which is lagging behind the PFA front-runners, may have the most to lose.
The analysts at Truist think Boston Scientific has the most to gain, especially in the near- to intermediate-term, “given its early mover advantage with Farapulse and limited existing EP share position, and we think this data supports share gains from existing ablation modalities,” they wrote in a note to investors. ADVENT data should support approval by the second half of 2024, they added.