A subanalysis of the THALES trial (NCT03354429) was presented at the American Heart Association's Scientific Sessions 2020 virtual meeting and published in Stroke. This subanalysis showed ticagralor plus aspirin treatment reduced the 1-month secondary stroke risk after transient ischemic attack (TIA) or acute stroke by 27% in those with atherosclerosis. For participants without atherosclerosis, the risk of secondary stroke or death was reduced by 11%, although this did not reach statistical significance. The number needed to treat (NNT) was 34 (95% CI, 19–171). Risk of severe bleeding was increased significantly for those without atherosclerosis.
These findings, coupled with previous research, supported an expanded indication for secondary stroke prevention recently granted for ticagrelor plus aspirin by the Food and Drug Administration (FDA).
In the THALES trial, 11,016 participants who had experienced acute stroke or TIA were randomly assigned to receive 75 to 100 mg of aspirin plus placebo or ticagrelor 180/mg day in 2 divided doses. Treatment began within 24 hours. Ipsilateral atherosclerosis was present in 21.4% (n=2,351). Among those with ipsilateral sclerosis, recurrent stroke or death within 30 days occurred in 8.1% (92/1,136) of those receiving aspirin plus ticagrelor and in 10.9% (132/1,215) of those receiving aspirin plus placebo (hazard ratio [HR], 0.73; 95% CI, 0.56-0.96; P=.023). Of those without ipsilateral sclerosis (n=8,665) treated with aspirin plus ticagrelor (n=4,287), 4.8% had a secondary stroke or died within 30 days vs 5.4% of those treated with aspirin alone (n=4,278) (HR, 0.89; 95% CI, 0.74-1.08; P=0.23)
“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, MD, 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.
Severe bleeding occurred in 4 (0.4%) and 3 (0.2%) individuals with ipsilateral atherosclerotic stenosis on ticagrelor plus aspirin and aspirin alone, respectively (P, not significant). In those without ipsilateral atherosclerosis, 24 (0.5%) treated with ticagrelor plus aspirin had severe bleeding vs 4 (0.1%) who were treated with aspirin alone (HR,5.87; 95% CI, 2.04-16.9; P=.001).
Ajay Sood, MD, PhD, and David Bennett, MD
Nupur Ghoshal, MD, PhD
Carlos E.V. Sollero, MD; Hsin-Pin Lin, MD; Miguel Chuquilin, MD; James Wymer, MD; and Aaron M. Carlson, MD