Faster clot-busting drug works as well as traditional drug for stroke
Newly approved tenecteplase, administered in a single rapid dose, may have advantages over alteplase for treating acute ischemic strokes, UTSW-led study shows
DALLAS – March 12, 2025 – A clot-busting drug recently approved to treat acute ischemic strokes (AIS) that can be delivered quickly works as well as a decades-old medication used by most hospitals in the U.S. and could hold significant advantages for some patients, a study led by a UT Southwestern Medical Center researcher shows. The findings, published in JAMA Network Open, could encourage more hospitals to use the newer drug, tenecteplase.
“In treatment of acute ischemic stroke, there is the saying that ‘time is brain.’ The longer patients go without effective treatment, the more brain cells die, and the worse their outcome will be. Our study shows that tenecteplase is a safe and effective alternative to traditional treatment with alteplase, and in some cases, it could get patients on the road to recovery faster,” said study leader Justin Rousseau, M.D., M.M.Sc., Associate Professor of Neurology and in the Peter O’Donnell Jr. Brain Institute at UT Southwestern. He also serves as Deputy Chief Medical Informatics Officer for Neurosciences at UTSW.
Each year, nearly 800,000 people in the U.S. have a stroke, a condition characterized by inadequate blood flow to the brain that ultimately kills brain cells. In AIS, which makes up the vast majority of strokes, this poor blood flow is caused by a clot. In 1996, a drug called alteplase was approved by the Food and Drug Administration (FDA) to treat AIS, nearly a decade after it was approved to treat heart attacks. It works by attaching to a protein in clots and activating an enzyme that dissolves them.
Although alteplase has been widely used for decades, it has significant disadvantages, Dr. Rousseau explained. Administered intravenously, alteplase is delivered with a rapid initial dose, with the remaining dose infused over the next hour. This complicated process can lead to interruptions in delivery of the medication or delay endovascular thrombectomy, a procedure to remove the clot, potentially leading to worse outcomes than if patients were treated faster.
The FDA approved tenecteplase in early March as an alternative to alteplase for treating AIS. Prior to FDA approval, tenecteplase had been approved for treatment of acute myocardial infarction (heart attack) and had been used off-label for treatment of AIS. This was supported through emerging evidence of the safety and effectiveness of tenecteplase compared with alteplase from stroke centers publishing their experience through clinical trials and further endorsed by inclusion of the use of tenecteplase in stroke guidelines.
Unlike alteplase, tenecteplase is delivered with a single, seconds-long injection, considerably speeding treatment time. Dr. Rousseau said hospitals have been slow to adopt tenecteplase, with less than 20% currently using it on a regular basis. One reason for this is a lack of data from routine clinical practice, he added. Although clinical trials have shown that the drugs have comparable safety and effectiveness, these studies don’t reflect variations in patient populations, severity of stroke, hospital characteristics, or physician practices.
To address this, Dr. Rousseau and his colleagues used data from the American Heart Association’s Get With The Guidelines – Stroke registry, a tool in which hospitals across the U.S. record data from tens of thousands of stroke patients each year. Using data collected between July 2020 and June 2022, the researchers found that 70,085 patients at participating hospitals received alteplase for AIS, while 9,465 received tenecteplase.
The groups had nearly identical effectiveness outcomes at hospital discharge, including in measures of functional independence, freedom from disability, discharge to home (rather than to a rehab facility or hospice), and independent ambulation (ability to walk without help from another person, if they could do this before their stroke). The two drugs were also comparable in multiple safety measures.
Sometimes patients with AIS who are eligible for endovascular thrombectomy don’t end up undergoing this procedure for a variety of reasons, including significant improvement after receiving clot-busting medications, significant pre-stroke disability, patient or family refusal, or lack of a specialist to perform the procedure. In this population, tenecteplase seemed to perform better than alteplase, improving the chances that they would be discharged to home and decreasing rates of in-hospital deaths or discharge to hospice.
Together, Dr. Rousseau said, these findings suggest that tenecteplase is a reasonable alternative to alteplase, offering significantly faster and simpler delivery and similar outcomes for AIS patients. He suggested that future studies could evaluate whether tenecteplase could lead to better outcomes than alteplase in patients who require transfer to advanced stroke centers to receive endovascular thrombectomies.
Ying Xian, M.D., Ph.D., Associate Professor of Neurology at UTSW, also contributed to this study. Dr. Rousseau’s mentor was Steven J. Warach, M.D., Ph.D., Professor of Neurology at Dell Medical School at UT Austin.
This research was funded in part by the Get With The Guidelines – Stroke American Heart Association/American Stroke Association Early Career Investigator Database Research Seed Grant.
About UT Southwestern Medical Center
UT Southwestern, one of the nation’s premier academic medical centers, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty members have received six Nobel Prizes and include 25 members of the National Academy of Sciences, 23 members of the National Academy of Medicine, and 14 Howard Hughes Medical Institute Investigators. The full-time faculty of more than 3,200 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide care in more than 80 specialties to more than 120,000 hospitalized patients, more than 360,000 emergency room cases, and oversee nearly 5 million outpatient visits a year.