Bayer releases data that could make stroke prevention drug the next big thing
For those who have experienced a stroke, the likelihood of a second stroke is high. An experimental drug from Bayer reduced that risk by 26% in a pivotal trial, bolstering its case as a potential new treatment option for patients. For Bayer, the drug presents the opportunity to be first to market in a new class of drugs that address large indications with blockbuster potential.
Bayer announced in November that the drug, asundexian, met the primary goal of a Phase 3 trial for secondary stroke prevention, but did not disclose any details at the time. The company did say it would begin communicating with health authorities as it prepares to submit its application to regulators. Bayer also said the data will be presented at an upcoming medical meeting. The data was released Thursday during the International Stroke Conference in New Orleans.
After a stroke, antiplatelet drugs and blood thinners (including aspirin, which Bayer still makes), can be used to prevent a second stroke. But these drugs can increase the risk of bleeding, especially with long-term use. Asundexian is a small molecule designed to block factor XIa, a protein in the coagulation cascade that plays a key role in hemostasis and thrombosis. By blocking this target, Bayer hopes to reduce the risk of stroke without increasing the risk of bleeding.
Bayer evaluated aundexian in OCEANIC-STROKE, a global Phase 3 study enrolling 12,327 participants representing all common stroke subtypes. The study drug was tested along with antiplatelet therapy and compared with placebo and antiplatelet therapy. The primary efficacy endpoint was time to ischemic stroke; the primary safety endpoint was time to first major bleeding.
In addition to meeting the primary goal of reducing the risk of ischemic stroke, the results also showed that asundexian met the secondary goal of reducing the risk of any type of stroke by 26%. Safety analysis showed no increase in the rate of major bleeding in the study drug group compared with placebo. In the results released by Bayer, Dr. Ashkan Shoamanesh, a senior scientist at the Population Health Research Institute and co-principal investigator of the study, said the sustained reduction in events secondary to all types of stroke was “particularly striking.”
“Ocean Stroke is carefully designed to allow the findings to be generalized to the multiple manifestations of stroke in clinical practice,” he said. “These results suggest that, if approved, aundexian could become an important option for secondary stroke prevention in a broad range of stroke patients.”
Asundexian previously posted disappointing data in another indication, failing Phase 3 testing in atrial fibrillation in 2023. In a conference call last year to discuss 2024 financial results, pharmaceuticals unit chief Stefan Oelrich attributed the clinical trial failure to the investigational drug's comparison with the highly effective standard treatment of Eliquis, a blood thinner marketed by Bristol-Myers Squibb and Pfizer. In contrast, asundexian's comparator in stroke studies is a placebo, he said.
Bayer is in the midst of a multi-year transformation, streamlining operations and seeking new revenue growth drivers. Asundexian may be one of them. Bayer has not yet provided specific financial forecasts for the drug, but on the call, Oelrich said that if aundexian's data readout is positive, the drug could become the first and only product approved for secondary stroke prevention.
“I can definitely see huge potential in this indication alone,” he said.
Ausndexian may face similar competition. Milvexian, a factor XIa inhibitor developed by Bristol-Myers Squibb and Johnson & Johnson in partnership, has reached Phase 3 testing for secondary prevention of stroke and atrial fibrillation. But the drug has its own drawbacks. In November, Bristol-Myers Squibb and Johnson & Johnson halted development of Milvexian in patients who experienced an acute coronary syndrome event. The companies said a pre-planned interim analysis concluded that the Phase 3 trial was unlikely to meet its primary endpoint.
Leerink Partners analyst David Risinger said in a research note that given Bayer's drug's Phase 3 success in secondary stroke prevention, the company gives Bristol's twice-daily drug an 80% chance of success in that indication. Phase 3 data on milvexian in stroke prevention and atrial fibrillation are expected later this year. The field of factor XI inhibitor drug candidates also includes two antibodies from Regeneron Pharmaceuticals, both in mid-stage clinical development.
Illustration: Micro Discovery via Getty Images
