HealthDay News — The use of alteplase between 4.5 and 9.0 hours after stroke onset results in a higher number of patients with no or minor neurological deficits, according to a study published in the May 9 issue of the New England Journal of Medicine.
Henry Ma, Ph.D., from the University of Melbourne in Australia, and colleagues conducted a multicenter randomized trial involving patients with ischemic stroke who had hypoperfused but salvageable regions of brain detected on automated perfusion imaging. Participants were randomly assigned to receive either intravenous alteplase (113 patients) or placebo (112 patients) between 4.5 and 9.0 hours after stroke onset or on awakening with stroke.
The trial was terminated after 225 of the planned 310 patients had been enrolled due to loss of equipoise following the publication of positive results from an earlier trial. The researchers found that the primary outcome (score of 0 or 1 on the modified Rankin scale) occurred in 35.4 and 29.5 percent of patients in the alteplase and placebo groups, respectively (adjusted risk ratio, 1.44). Symptomatic intracerebral hemorrhage occurred in 6.2 and 0.9 percent of patients in the alteplase and placebo groups, respectively (adjusted risk ratio, 7.22).
“Because of the limited power of our conclusions as a result of premature termination of the trial and the lack of a significant between-group difference in the secondary outcome of functional improvement, further trials of thrombolysis in this time window are required,” the authors write.
Several authors disclosed financial ties to the biopharmaceutical industry.