Research Highlights:

  • Patients who suffered a “warning stroke” were less likely to have another stroke or die within 30 days if treated with a combination of aspirin and a newer blood thinner, ticagrelor.
  • Researchers say that for patients with minor stroke treated within 24 hours of symptom onset, clinicians should consider the combination of ticagrelor plus aspirin to prevent a subsequent stroke.

Embargoed until 7:22 p.m. CT/8:22 p.m. ET, Monday, Nov. 16, 2020

DALLAS, Nov. 16, 2020 — Patients with plaque build-up in their arteries, who suffered a transient ischemic attack (TIA) or a minor ischemic stroke, also called a warning stroke, and were treated with the newer blood thinner ticagrelor plus aspirin were 27% less likely to have another stroke within 30 days, according to late-breaking research presented today at the American Heart Association’s Scientific Sessions 2020. The virtual meeting is Friday, November 13-Tuesday, November 17, 2020, and is a premier global exchange of the latest scientific advancements, research and evidence-based clinical practice updates in cardiovascular science for health care worldwide. The manuscript of this study is simultaneously published today in Stroke, a journal of the American Heart Association.

In this sub-analysis of the THALES trial, The Acute Stroke or Transient IscHemic Attack Treated with Ticagrelor and Aspirin for PrEvention of Stroke and Death trial, ticagrelor benefitted patients with plaque build-up in their arteries (atherosclerosis) more than patients whose stroke had another cause. These findings, coupled with previous research, show a combination of both ticagrelor and aspirin is more effective than either medication alone.

“In our opinion, health care professionals should now consider both ticagrelor and aspirin to prevent another stroke in patients who experience a warning stroke. Our research shows treating patients within 24 hours of their first symptoms using this newer regimen is effective, especially when the cause of the stroke is due to plaque build-up in the arteries,” said the study’s lead author Pierre Amarenco, M.D., professor of neurology at Paris University and chair of the department of Neurology and Stroke Center and the SOS-TIA clinic at Bichat hospital in Paris, France.

Of the more than 11,000 participants originally enrolled in the multinational THALES trial (conducted in 2018 and 2019), about one in five (2,351) had plaque build-up in their arteries. Researchers randomized those patients into two groups - aspirin plus ticagrelor or aspirin alone - to identify whether the combination of medications was a more effective treatment than either medication on its own.

After an initial dose of 180 mg, researchers added 90 mg twice a day of ticagrelor to 75-100 mg of daily aspirin for one month, and the risk of another stroke or death was reduced by 27% among these patients.

The THALES trial is a randomized, placebo-controlled, double-blind, international, multi-site study. It is currently in Phase III and began in January of 2018.

Co-authors are Hans Denison, M.D., Ph.D.; Scott. R. Evans, Ph.D.; Anders Himmelmann, M.D., Ph.D.; Stegan James, M.D., Ph.D.; Mikael Knuttson, Ph.D.; Per Ladenvall, M.D., Ph.D.; Carlos Molina, M.D., Ph.D.; Yongjun Wang, M.D.; Claiborne Johnston, M.D., Ph.D. Author disclosures are in the abstract. The study was funded by AstraZeneca.

Note: Session: LBS.07 - Randomized Trials – Brain, Kidney, and Heart

Additional Resources:

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