# FDA Approves First Factor XIa Blood Thinner to Prevent Repeat Strokes

> Bayer's Sunharbo, taken once a day with antiplatelet therapy, cut ischemic strokes by 26 percent in a trial of more than 12,000 adults.

- Publication: New England Anti-Aging (https://newenglandantiaging.com)
- Section: Primary Care
- Author: Nina Ferraro, Health and Science Editor
- Published: 2026-11-09
- Lead photograph: An older man and woman standing together outdoors, by Centre for Ageing Better on Unsplash (https://unsplash.com/@ageing_better)
- Canonical URL: https://newenglandantiaging.com/primary-care/fda-approves-sunharbo-stroke/

## The Short Version



The Food and Drug Administration on Monday approved Sunharbo, a once-daily pill from Bayer, to lower the risk of another stroke in adults who recently had a mild to moderate ischemic stroke or a high-risk transient ischemic attack, often called a mini-stroke. [According to the agency](https://www.fda.gov/news-events/press-announcements/fda-approves-first-factor-xla-inhibitor-help-prevent-stroke-certain-adults-high-risk), it is the first drug in a new class called factor XIa inhibitors to reach the U.S. market.

The drug, known generically as asundexian, is taken with standard antiplatelet therapy such as aspirin. It is approved only for strokes caused by a clot that did not start in the heart. It is not approved for people with atrial fibrillation, whose strokes are usually treated with other anticoagulants.

Approval was based on OCEANIC-STROKE, a trial of 12,327 adults enrolled within 72 hours of their stroke or TIA. Over a median of about 14 months, those taking Sunharbo had 26 percent fewer ischemic strokes than those taking a placebo.

Overall major bleeding was similar between the groups, but it rose in patients older than 75 and during the first 90 days of treatment. Gastrointestinal bleeding was more common with the drug. The FDA said Sunharbo should be paused at least 24 hours before planned surgery and is not recommended for people with moderate or severe liver disease.

Factor XIa inhibitors have drawn interest because they target a part of the clotting system thought to matter more for dangerous clots than for normal healing, which researchers hope could mean less bleeding than older blood thinners. Whether that holds up in wider use will become clearer as more patients take it.

For stroke survivors, the practical step is a conversation with the neurologist or primary care clinician who manages their prevention plan. Blood pressure control, cholesterol treatment and not smoking remain the foundation, as we explained in our look at the [2025 blood pressure guideline](/primary-care/blood-pressure-guideline-2025/).

## Notes and Sources

1. FDA Approves First Factor XIa Inhibitor to Help Prevent Stroke in Certain Adults at High Risk. U.S. Food and Drug Administration, 2026. https://www.fda.gov/news-events/press-announcements/fda-approves-first-factor-xla-inhibitor-help-prevent-stroke-certain-adults-high-risk

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Published by New England Anti-Aging, the health and longevity magazine of Align Wellness, 250 Centerville Rd, Building E, Warwick, RI 02886. General information only, not medical advice.