What the OCEANIC-STROKE Data Suggest About Stroke Prevention: Mike Sharma, MD

The lack of a statistically significant difference at 90 days for the oral Factor XIa (FXIa) inhibitor asundexian (Sunharbo; Bayer) in noncardioembolic ischemic stroke prevention should be interpreted in the context of the trial’s statistical power, as only about 40% of the outcome events needed to detect the planned difference occurred, a shortfall that may explain the result, especially since, as an antithrombotic, asundexian is expected to act quickly. Mike Sharma, MD, MSc, professor of medicine at McMaster University, made the case in part 2 of an interview on the phase 3 OCEANIC-STROKE (NCT05686070) trial, which evaluated asundexian for secondary stroke prevention and was presented at the American Heart Association (AHA) Scientific Session.

Sharma points to the study’s outcome curves, which began separating early and continued to diverge over a median follow-up of 19 months. He describes this pattern as consistent with an ongoing treatment effect, while acknowledging that projections beyond the observed follow-up are based on the evidence. He recommends continuing therapy while stroke risk remains, noting that risk does not disappear with time and may rise as people age.

The interview also emphasizes the human impact of recurrent stroke. Sharma says survivors can experience anxiety, depression, and post-traumatic stress, and many strongly wish to avoid another stroke. He adds that in the trial, strokes that occurred were less severe and less likely to cause disability, a potential benefit beyond reducing the number of events.

A central lesson, Sharma says, is that antithrombotic treatments should be developed for the disease being treated. Atrial fibrillation, acute coronary syndrome, and ischemic stroke are distinct conditions, and a dose that worked in non-cardioembolic stroke was not successful in atrial fibrillation. Earlier drug development often tested antithrombotics in heart conditions before stroke, but Sharma argues that approach could miss the dose or regimen needed for stroke patients. The interview therefore underscores the importance of condition-specific research, attention to stroke prevention, and measuring disability outcomes alongside event rates.