FDA Approves Asundexian, First FXIa Inhibitor for Stroke Prevention

The FDA has approved asundexian (Sunharbo), a once-daily factor XIa (FXIa) inhibitor added with antiplatelet therapy for adults with a recent ischemic stroke or high-risk transient ischemic attack (TIA). According to trial findings, once-daily asundexian combined with antiplatelet therapy cut the risk of ischemic stroke by 26% compared with placebo, according to an FDA release.¹

“For those who survive a stroke, the risk of another potentially devastating event is highest in the days and weeks after the initial event, and that risk persists over time,” said Ashkan Shoamanesh, MD, co-principal investigator of the OCEANIC-STROKE clinical study and senior scientist at Population Health Research Institute, according to a Bayer release.² “I believe asundexian introduces an important new addition to post-stroke care that can be used to help patients reduce the risk of a secondary stroke.”

Hylton V. Joffe, MD, MMSc, director of the Office of Cardiology, Hematology, Endocrinology, and Nephrology in the FDA Center for Drug Evaluation and Research (CDER), emphasizes that stroke remains a leading cause of disability and death in the US, leaving survivors at constant risk of recurrence. The urgency of this approval is underscored by national health data showing that nearly 795,000 individuals suffer a stroke in the US each year, with approximately one in 10 survivors experiencing a recurrent event within 1 year and one in 5 within 5 years.^1,2

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By selectively inhibiting FXIa, asundexian uncouples hemostasis from pathological thrombosis, allowing for reduced blood clot formation while maintaining a major bleeding rate similar with placebo.²

Clinical Considerations and Safety Protocols for Pharmacy Practice

Despite asundexian offering clear clinical efficacy, community pharmacists must remain vigilant regarding its specific safety profile and drug interactions.¹

Clinical trial findings indicate that the overall rate of major bleeding remained comparable with placebo, yet major bleeding risk increased among patients older than 75 and during the initial 90 days of treatment. Gastrointestinal bleeding occurred more frequently with asundexian, and diarrhea emerged as the most common adverse reaction, affecting 3% or more of treated patients.

Furthermore, pharmacists must evaluate drug interaction profiles, as concomitant administration with combined P-glycoprotein and strong CYP3A4 inducers, such as carbamazepine, is not recommended due to potential efficacy reduction.¹

Community pharmacists should also advise patients that asundexian must be withheld at least 24 hours prior to elective surgeries or invasive procedures, as well as 24 hours following thrombolytic therapy, and note that it is not approved for patients with atrial fibrillation or moderate-to-severe hepatic impairment.

The Critical Role of Community Pharmacists in Post-Stroke Transition Care

The arrival of asundexian highlights the vital leadership role community pharmacists maintain in secondary stroke prevention and care transitions. Because community pharmacists are among the most accessible providers, they are uniquely positioned to educate ambulatory stroke survivors on medication therapy management, modifiable risk factors, and lifestyle adjustments.³

Comprehensive systematic reviews demonstrate that pharmacist-led interventions focusing on blood pressure management, cholesterol control, and lifestyle counseling can help prevent up to 80% of recurrent strokes. Pharmacist-led initiatives have been shown to increase appropriate antithrombotic therapy optimization by 34%, while also supporting patients through dietary counseling on the Mediterranean diet and encouraging weekly physical activity goals.^3,4

Seamless collaboration between hospital pharmacists and community retail pharmacists is essential during post-discharge transitions to prevent therapy interruptions. Recent research on bidirectional pharmacist communication tools reveal that structured information sharing resolved 75% of post-discharge medication discrepancies, lowering unresolved discrepancies from 16 to 4 drugs and raising community pharmacist intervention rates to 100%.⁵

Community pharmacists actively safeguard medication continuity through services such as one-dose packaging, checking remaining pill counts, conducting adherence follow-ups, and offering at-home visits. As asundexian enters retail pharmacy channels, community pharmacists will serve as the essential front line, verifying prescribing appropriateness, monitoring safety parameters, and empowering patients to achieve lasting stroke prevention.^3,5

“Stroke is a leading cause of disability and death in the US, and survivors are at risk of having another stroke,” concluded Joffe, according to the current release.¹ “Today’s approval represents a meaningful advance for patients and health care providers seeking a new option for secondary stroke prevention.”

READ MORE: Cardiology Resource Center

REFERENCES

1. FDA approves first factor XIa inhibitor to help prevent stroke in certain adults at high risk. FDA. News Release. November 9, 2026. Accessed November 11, 2026. https://www.fda.gov/news-events/press-announcements/fda-approves-first-factor-xla-inhibitor-help-prevent-stroke-certain-adults-high-risk

2. Bayer’s asundexian first FXIa inhibitor approved by U.S. Food and Drug Administration for secondary stroke risk reduction. Bayer. News Release. November 10, 2026. Accessed November 11, 2026. https://www.bayer.com/media/en-us/bayers-asundexian-first-fxia-inhibitor-approved-by-us-food-and-drug-administration-for-secondary-stroke-risk-reduction/

3. Viviandhari D, Andayani TM, Paryono, et al. Pharmacist-led patient education in secondary stroke prevention: a systematic review. Malays J Med Sci. 2025;32(2):7-22. doi:10.21315/mjms-01-2025-043

4. Gershman J. Pharmacists play vital role in stroke prevention. Pharmacy Times. February 20, 2025. Accessed November 11, 2026. https://www.pharmacytimes.com/view/pharmacists-play-vital-role-in-stroke-prevention

5. Fukuda Y, Ito R, Kakihana M, et al. Effects of hospital pharmacist-community pharmacist collaboration on solving pharmacotherapy problems in stroke patients with post-discharge transitions: non-randomized comparative study. BMC Neurol. 2025;25(1):459. 2025 Nov 7. doi:10.1186/s12883-025-04474-0