Giving alteplase, a clot-busting drug, directly into a blocked brain artery after removing a blood clot may improve recovery rates for stroke patients, according to new findings presented at the American Stroke Association's International Stroke Conference 2026 in New Orleans. The conference brings together researchers and clinicians focused on stroke and brain health.
Large-artery ischemic strokes, which account for about one in four ischemic strokes, can lead to death or long-term disability due to blockage of major arteries supplying blood to the brain. Ángel Chamorro, M.D., Ph.D., professor of neurology at the University of Barcelona and head of the Comprehensive Stroke Center Hospital Clinic in Barcelona, explained that these strokes have significant impacts because they affect large portions of the brain.
The current standard treatment for these types of strokes is thrombectomy—removing clots from blocked arteries. According to Dr. Chamorro, "Mechanical thrombectomy alone is often not enough to fully restore blood flow to the injured brain, even when the blocked artery appears successfully reopened. Standard imaging can miss persistent blockages in the brain's smallest blood vessels. Intra-arterial alteplase given after successful thrombectomy significantly increased the chances of an excellent recovery."
The CHOICE2 trial included more than 400 adults with large-artery ischemic stroke treated at centers in Spain within 4.5 to 24 hours after their first symptoms. Patients were randomized into two groups: one received only clot removal (219 people), while the other group received both clot removal and an infusion of alteplase directly into the artery (214 people). At 90 days post-treatment, those who received alteplase in addition to thrombectomy showed improved outcomes.
Previous research supports these findings. The earlier CHOICE study published in 2022 found better outcomes among stroke survivors treated with both procedures; however, that study was limited by its small sample size and early termination during the COVID-19 pandemic. Other trials such as ANGEL-TNK (using tenecteplase) and PEARL (using alteplase) have reported similar results.
One limitation noted was that follow-up involved non-contrast CT scans—a common clinical practice—which might not provide detailed information about tissue injury or recovery.
While this study took place only in Spain, participants represented 20 countries across three continents, suggesting broad applicability.
Chamorro stated: "These results are practice-informing but not yet practice-changing on their own," adding that further studies are needed before this approach becomes widely adopted. He emphasized that intra-arterial alteplase may be most beneficial for patients whose microcirculation remains compromised despite reopening large vessels: "Importantly, this approach should not be viewed as a 'one-size-fits-all' treatment. It is most likely to benefit patients who, despite large-vessel reopening, have evidence of inadequate blood flow in their microcirculation. However, if future studies and meta-analyses confirm the safety of this strategy, it may eventually reduce the need to rely on advanced imaging techniques to identify patients with persistent perfusion abnormalities appropriate for this treatment."
Future research will also explore how best to address problems with microcirculation following major strokes.
