Asundexian Reduces Risk of Future Ischemic Stroke as Secondary Prevention

In the phase 3 OCEANIC-STROKE study (NCT05686070), asundexian (Bayer), an investigational, once-daily, oral factor XIa (FXIa) inhibitor, reduced the risk of ischemic stroke compared with placebo in combination with antiplatelet therapy. The effects were seen in a cohort of patients who previously experienced a non-cardioembolic ischemic stroke or a high-risk transient ischemic attack.^1,2

Critically, there was no increase in the risk of major bleeding as defined by the International Society on Thrombosis and Haemostasis in patients treated with asundexian compared with placebo. The results were announced in a news release from Bayer, with future data expected to be presented at an upcoming scientific meeting, according to the authors.¹

The Burden of Stroke

“As clinicians, we see every day how devastating a recurrent stroke can be for patients and their families. Even with currently available therapies, the risk of another stroke remains high, and each recurrence can have profound consequences,” Mike Sharma, MD, a principal investigator of the OCEANIC-STROKE study and director of the stroke program at Hamilton Health Services, said in the news release.¹

Stroke constitutes a major burden globally; it’s the second leading cause of death across the world, and each year, 12 million individuals experience a stroke. After a stroke, the resulting disability is often significant. Patients could face paralysis on one side of their body, difficulties speaking or finding which words to say, memory loss, and vision problems, among others. Beyond the physical impacts after a stroke, many patients ultimately experience a recurrent stroke. There is a concerning increase in stroke incidence among young and middle-aged individuals, necessitating new treatment capabilities.^1,3,4

“The topline results from OCEANIC-STROKE indicate that asundexian may become a new treatment option to reduce this risk—representing a potential major step forward in secondary stroke prevention,” Sharma continued.¹

Asundexian's Background, Safety, and Tolerability

OCEANIC-STROKE has enrolled over 12,000 patients since its initiation. Results from the multicenter, international, randomized, placebo-controlled, double-blind, parallel-group, event-driven study could further bolster asundexian’s regulatory status. In 2022, the FDA granted the agent fast track designation based on positive results from a phase 2 (NCT04304508) study. Future clinical trial research could mean further regulatory movement for asundexian based on FDA decisions.^1,5

Asundexian is a small molecule that binds and inhibits the activity of FXIa. The agent selectively inhibits the intrinsic coagulation pathway, thereby preventing thrombosis without hindering clotting responses that initiate after an injury. Although FXIa only has a small role in the formation of a seal at the site of a vessel injury, it is thought to contribute to the formation of pathological thrombus growth and vessel blockage. Asundexian achieves reductions in thrombus formation without major increases in rates of significant bleeding.^1,5

In phase 1 studies, asundexian appeared to be well-tolerated. Common treatment-emergent adverse events included headache and nasopharyngitis, but all events were considered mild. Furthermore, all events were considered mild, with no clinically significant examinations or procedures observed in any patients. The current phase 3 results did not fully reveal safety indications, but the lack of increase in risk of major bleeding was a major demonstration of tolerability across the population.^1,5

REFERENCES

1. Bayer. Bayer’s asundexian met primary efficacy and safety end points in landmark phase III OCEANIC-STROKE study in secondary stroke prevention. News release. Bayer. Published November 23, 2025. Accessed December 4, 2025. https://www.bayer.com/en/us/news-stories/oceanic-stroke

2. A study to test asundexian for preventing a stroke caused by a clot in participants afteran acute ischemic stroke or after a high-risk transient ischemic attack, a so-called mini stroke (OCEANIC-STROKE). ClinicalTrials.gov Identifier: NCT05686070. Last Updated November 12, 2025. Accessed December 4, 2025. https://www.clinicaltrials.gov/study/NCT05686070

3. Feigin VL, Owolabi MO, et al. Pragmatic solutions to reduce the global burden of stroke: a World Stroke Organization–Lancet Neurology Commission. Lancet Neurol. 2023;22(12):1160-1206. doi:10.1016/S1474-4422(23)00277-6

4. Effects of stroke. American Heart Association. Accessed December 4, 2025. https://www.stroke.org/en/about-stroke/effects-of-stroke

5. Rhoads AT. Clinical overview: Asundexian for secondary prevention in patients with non-cardioembolic ischemic stroke. Pharmacy Times. Published May 16, 2022. Accessed December 4, 2025. https://www.pharmacytimes.com/view/clinical-overview-asundexian-for-secondary-prevention-in-patients-with-non-cardioembolic-ischemic-stroke