Bayer’s experimental blood thinner asundexian cut the relative likelihood of a repeat stroke by 26% without increasing the risk of internal bleeding, the company said Thursday, boosting hopes that the company might become a new option for “secondary treatment” of the disorder.
The news could also elevate the outlook for medicines like asundexian, which are called Factor XIa inhibitors and are being advanced by a handful of the world’s largest pharmaceutical companies.
Members of that drug class, including asundexian and a similar therapy from Bristol Myers Squibb and Johnson & Johnson, have previously suffered clinical setbacks in different types of cardiovascular illnesses. But asundexian’s success, first announced in November, lifted Bayer shares and indicated the drugs might be able to fulfill at least some of their commercial potential.
The German drugmaker released full data from its positive study, “Oceanic-Stroke,” at the International Stroke Conference in New Orleans on Thursday.
Physicians treating patients with blood-thinning agents to prevent dangerous clots must tread a fine line to protect them from internal bleeding. A generic drug called clopidogrel, as well as AstraZeneca’s Brilinta, already increase the chances of these bleeds. Additional therapies need to ensure they don’t raise that risk even higher.
Drug companies hope that medicines inhibiting Factor XIa — which has a bigger role in building clots than controlling bleeding — might be a lower-risk way of preventing further strokes and other cardiovascular events.
In the trial, Bayer enrolled more than 12,000 people who’d had a stroke or a high-risk, transient ischemic attack. Those participants were then randomized to take asundexian or a placebo on top of other anti-clotting therapies.
The 26% relative reduction in the risk of strokes in asundexian recipients was statistically significant. Meanwhile, 1.9% of enrollees who got asundexian experienced a bleeding incident versus 1.7% of those who got a placebo — a difference that wasn’t deemed consequential.
“For clinicians and researchers who have spent decades working to reduce the global burden of secondary stroke, the Oceanic-Stroke results represent the kind of scientific progress the field has long been striving to achieve,” said Mike Sharma, the study’s principal investigator and a McMaster University stroke specialist, in a statement provided by Bayer.
Prior to Bayer’s success, asundexian fell short in a stroke-prevention trial in people with atrial fibrillation. More recently, the Bristol Myers and J&J pill milvexian missed in acute coronary syndrome.
Since the Oceanic-Stroke findings were first announced, though, Wall Street analysts have become more optimistic about Factor XIa inhibitors, which also includes two biologic drugs from Regeneron.
