Boston Scientific resumes Farapulse pulsed field ablation study in first-line afib

Late last month, Boston Scientific announced it was pausing a study examining pulsed field ablation as a first-line therapy. Now, it has resumed its work to see whether its Farapulse platform can deliver results for patients with atrial fibrillation before they take any anti-arrhythmic medications.

The study, dubbed AVANT GUARD, had reported “a few unanticipated observations” as it approached its full enrollment goal, according to CEO Mike Mahoney on the company’s third-quarter earnings call in late October.

In addition, Boston Scientific’s global chief medical officer, Kenneth Stein, M.D., said at the time that the findings were not life-threatening but that the company was unable to provide additional details on the ongoing, blinded trial.

AVANT GUARD was launched in late December 2023 with the goal of recruiting at least 500 patients with persistent afib that lasts longer than a week; its first participant was signed up at the Cleveland Clinic.

Last week, in a filing with the Securities and Exchange Commission, the company said it had assessed the data and that the decision to continue was made in conjunction with the trial’s data monitoring committee.

In an interview with Fierce Medtech following the study’s pause, Stein characterized the trial as a big bet on the potential of pulsed field ablation technology.

“No one has previously done a large, randomized trial looking at any ablation modality in persistent atrial fibrillation patients as a first-line therapy,” he said during the TCT conference in Washington, D.C., in October.

“So what we're doing in AVANT GUARD is we’re looking at patients with their new diagnosis of persistent atrial fibrillation, who haven't even been given a drug therapy yet, and randomizing them to drug therapy versus immediately proceeding to ablation … What gives us some of the confidence, where we say this is worth studying, is that it has been studied for paroxysmal atrial fibrillation and the data really did support moving to early ablation,” he said.

“[W]e disclosed that we paused the trial because we want to understand some unexplained observations that we saw in the trial … the frustrating thing about that is we can't go into a lot of details about what we saw in the trial because we need to preserve blinding and make sure we can get the trial done successfully,” Stein said.

Alongside the pause announcement on the company’s third-quarter earnings call, Boston Scientific also reported that sales in its electrophysiology division were up 177% year over year following the launch of Farapulse this past spring.