The Food and Drug Administration on Monday, Nov. 9, approved a new kind of blood thinner for people who have just had a stroke. Bayer's Sunharbo (asundexian) is the first factor XIa inhibitor cleared in the United States, and it is meant to lower the chance of a second stroke.

It is a once-daily 50 mg tablet. Patients take it along with the antiplatelet medicine they would usually get after a stroke. The approval covers adults who recently had a mild-to-moderate ischemic stroke that was not caused by a clot from the heart, or a high-risk transient ischemic attack, the brief blockage often called a mini-stroke. People with atrial fibrillation, a common heart rhythm problem, are not covered.

China approved the drug first, on Oct. 26, according to Bayer, which called it the first factor XIa inhibitor approved anywhere. About 1 in 10 survivors of this type of stroke have another one within a year, even with current treatment, the company says.

What the study found

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FDA Building 31 at the agency's White Oak campus in Silver Spring, Md.U.S. Food and Drug Administration / Wikimedia Commons.jpg) / Public domain

The FDA based its decision on a trial of 12,327 adults who started the drug or a placebo within 72 hours of their symptoms, with everyone also taking antiplatelet therapy. Over a median of about 14 months, the drug cut the risk of another ischemic stroke by 26% compared with placebo.

Bleeding results were mixed. Overall rates of major bleeding were similar in the two groups, with two exceptions the FDA flagged. Major bleeding was more common with Sunharbo in patients older than 75 and during the first 90 days of treatment, and stomach and intestinal bleeding was more common with the drug overall. The most common side effect was diarrhea.

What patients should know

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Image: Edit USA

The FDA advises against taking Sunharbo with certain drugs, such as the seizure medicine carbamazepine, that can make it less effective. It is not recommended for moderate or severe liver impairment. Patients are told to stop it at least 24 hours before planned surgery or other invasive procedures and to wait at least 24 hours after clot-busting treatment for a stroke before taking it.

Neither the FDA nor Bayer's earlier release says what the drug will cost in the United States or when pharmacies will stock it.

People who have had a stroke or mini-stroke should ask a neurologist or primary care doctor whether it fits their situation.