FDA approves Bayer's asundexian (Sunharbo) to cut repeat stroke risk in some adults

Approval and who it covers

The US Food and Drug Administration has approved Sunharbo, the brand name for asundexian, to reduce the risk of another stroke in certain adults. Bayer announced the decision on 10 November. The drug is taken orally once a day together with antiplatelet therapy. It covers adults with a recent mild or moderate ischemic stroke caused by a clot that did not come from the heart, as well as adults with a high-risk transient ischemic attack. Bayer described it as the first drug approved anywhere in the world from this new class of factor XIa inhibitors. It is not approved to prevent strokes in patients with atrial fibrillation.

Trial results and safety

The approval rests on OCEANIC-STROKE, a phase 3 trial of 12,327 adults. Participants received either asundexian or placebo within the first 72 hours after symptoms began, and both groups also took antiplatelet drugs. The 50 mg daily dose reduced the risk of ischemic stroke by 26% compared with placebo over a median treatment period of 14.2 months. Overall rates of serious bleeding were similar, but they rose with asundexian in people over 75 and during the first 90 days of treatment. Gastrointestinal bleeding also increased. Bayer's research chief, Christian Rommel, said the approval marked significant progress in stroke aftercare and aimed to close gaps in care.

Market, pricing and Bayer's bet

Sebastian Guth, Bayer's US head, told Reuters that about 800,000 strokes occur in the US each year and that recurrence rates have stayed high for 20 years. Bayer sells the drug itself in the US, with a list price of $748.50 per month. The drug is aimed at about 40% of all stroke patients. Asundexian is meant to fill the gap left as patent protection ends for Xarelto, a blood thinner that was a bestseller. Guth said Bayer has largely moved past that patent cliff. The company considers the drug to have blockbuster potential, meaning peak annual sales above one billion euros. On 10 November Bayer shares rose about 2% at times to a year high of 57.78 euros, and early Frankfurt trading showed a gain of 1.4%. Deutsche Bank raised its price target to 65 euros from 60. Jefferies analysts called the approval an important step in reducing risk in Bayer's pipeline.

Previous target60

New target65

Previous target

60 EUR

New target

65 EUR

Data from the article text

Developed in Wuppertal, launched elsewhere first

The drug was discovered and developed at Bayer's site in Wuppertal, but it reaches patients first in China and the United States. China has already approved it, with one report placing that approval in October. Germany and Europe still have to wait. Bill Anderson, Bayer's chief executive, praised the Wuppertal team at the company's results presentation in early November, crediting artificial intelligence and a new organisational model with shortening the timeline by a year.

“They invented this molecule and worked on it for more than a decade.”

Bayer is not alone. Drugs often launch first in the US, where higher prices and lower regulatory hurdles are the main reasons cited. Boehringer Ingelheim's lung cancer drug Hernexos is approved in the US but remains far from Europe, where authorities reportedly demand considerably more extensive studies. The trade group Verband Forschender Arzneimittelhersteller says roughly a third of drugs approved in the US between 2016 and 2025 never received European approval.