The US Food and Drug Administration has approved a new blood thinner, asundexian (brand name Sunharbo), developed by Bayer, to prevent secondary strokes in people who have recently suffered a stroke or transient ischemic attack. It is the first approved treatment that blocks the clotting protein Factor XIa, offering a novel approach to reducing the risk of repeat episodes.
The decision follows positive results from a global Phase 3 clinical trial. Asundexian, taken orally once daily, inhibits Factor XIa, which is believed to contribute to pathological thrombus growth and vessel blockage, or clotting. Existing blood thinners target a different protein, Factor Xa.
The chance of a stroke survivor experiencing a second stroke within five years is estimated to be around one in five, and such events can be more dangerous and debilitating than the first. “For those who survive a stroke, the risk of another potentially devastating event is highest in the days and weeks after the initial event, and that risk persists over time,” said Ashkan Shoamanesh, senior scientist at the Population Health Research Institute, a joint institute of Hamilton Health Sciences and McMaster University, Ontario. “I believe asundexian introduces an important new addition to post-stroke care that can be used to help patients reduce the risk of a secondary stroke.”
Bayer said in a news release that asundexian “reduces the risk of secondary stroke” in combination with antiplatelet therapy and is “the first approved drug in a new class of Factor XIa inhibitors worldwide.”
Nearly 800,000 Americans are estimated to suffer a stroke each year, and stroke remains one of the leading causes of death globally.
Analysis
Why This Matters
- Offers a new prevention option for the roughly one in five stroke survivors who face a repeat event within five years, reducing the potential for more severe disability or death.
- Targets a different clotting protein than existing drugs, potentially opening a new class of treatments for cardiovascular conditions.
- Could influence clinical practice for post-stroke care if real-world outcomes match trial results.
Background
Stroke is a leading cause of death and disability worldwide. Secondary strokes are often more dangerous than the first, making effective prevention critical. Existing blood thinners inhibit Factor Xa, whereas asundexian blocks Factor XIa, a mechanism that had not been targeted by approved drugs. Bayer's approval follows a global Phase 3 study, though detailed results have not been released in the available material.
Key Perspectives
Bayer: says asundexian, taken once daily, reduces the risk of secondary stroke when used with antiplatelet therapy, and is the first approved drug in a new class of Factor XIa inhibitors.
Ashkan Shoamanesh (Population Health Research Institute): says the risk of another stroke is highest in the days and weeks after the initial event and persists over time, and believes asundexian adds an important new option to post-stroke care.
What to Watch
- Publication of the full Phase 3 trial data, which will clarify efficacy and safety details.
- Uptake in clinical practice and any coverage decisions by insurers and national health systems.
- Whether the drug is studied for other clotting-related conditions beyond stroke prevention.
Checked
12 claims in this story checked against 1 source: 12 supported.
Show each claim
- SupportedBayer won FDA approval for a first-in-class blood thinner to prevent repeat strokes.New Atlas: Technology-Innovation-Outdoor News: “A first-in-class blood thinner has been approved by the US Food and Drug Administration to prevent repeat strokes”
- SupportedThe FDA approved asundexian, developed by Bayer, to prevent secondary strokes in people recently affected by a stroke or transient ischemic attack.New Atlas: Technology-Innovation-Outdoor News: “The drug, asundexian (brand name Sunharbo) developed by Bayer has become the first treatment approved in the US designed to prevent blood clots by blocking a specific protein”
- SupportedAsundexian is the first approved treatment that blocks Factor XIa, a protein not targeted by medications currently on the market.New Atlas: Technology-Innovation-Outdoor News: “has become the first treatment approved in the US designed to prevent blood clots by blocking a specific protein that hasn't been targeted by medications currently on the market.”
- SupportedAshkan Shoamanesh said the risk of another potentially devastating event is highest in the days and weeks after a stroke and persists over time.New Atlas: Technology-Innovation-Outdoor News: ““For those who survive a stroke, the risk of another potentially devastating event is highest in the days and weeks after the initial event, and that risk persists over time,” says Ashkan Shoamanesh, M.D.”
- SupportedShoamanesh said asundexian could be an important addition to post-stroke care to help reduce secondary-stroke risk.New Atlas: Technology-Innovation-Outdoor News: ““I believe asundexian introduces an important new addition to post-stroke care that can be used to help patients reduce the risk of a secondary stroke.””
- SupportedBayer said asundexian reduces secondary-stroke risk when used with antiplatelet therapy.New Atlas: Technology-Innovation-Outdoor News: ““Asundexian, an oral, once-daily Factor XIa inhibitor, reduces the risk of secondary stroke, in combination with antiplatelet therapy”
- SupportedBayer described asundexian as the first approved drug in a new class of Factor XIa inhibitors worldwide.New Atlas: Technology-Innovation-Outdoor News: “is the first approved drug in a new class of Factor XIa inhibitors worldwide,” Bayer notes in its official news release.”
- SupportedThe approval followed positive results from a global Phase 3 clinical trial.New Atlas: Technology-Innovation-Outdoor News: “The approval was granted following positive results from a global Phase 3 study.”
- SupportedAsundexian is taken orally once daily and inhibits Factor XIa.New Atlas: Technology-Innovation-Outdoor News: “Asundexian, an oral, once-daily Factor XIa inhibitor”
- SupportedExisting blood thinners target Factor Xa rather than Factor XIa.New Atlas: Technology-Innovation-Outdoor News: “Sunharbo stops the clotting protein Factor XIa (FXIa), as opposed to existing medications that take aim at a different protein known as Factor Xa.”
- SupportedThe estimated chance of a stroke patient having a secondary episode within five years is one in five.New Atlas: Technology-Innovation-Outdoor News: “The chances of stroke patients experiencing a secondary episode within five years is estimated to be one in five”
- SupportedNearly 800,000 Americans are estimated to suffer a stroke each year.New Atlas: Technology-Innovation-Outdoor News: “It's estimated nearly 800,000 Americans suffer a stroke each year”