Thrombolysis with alteplase 3 to 4.5 hours after acute ischemic stroke

N Engl J Med. 2008 Sep 25;359(13):1317-29. doi: 10.1056/NEJMoa0804656.

Abstract

Background: Intravenous thrombolysis with alteplase is the only approved treatment for acute ischemic stroke, but its efficacy and safety when administered more than 3 hours after the onset of symptoms have not been established. We tested the efficacy and safety of alteplase administered between 3 and 4.5 hours after the onset of a stroke.

Methods: After exclusion of patients with a brain hemorrhage or major infarction, as detected on a computed tomographic scan, we randomly assigned patients with acute ischemic stroke in a 1:1 double-blind fashion to receive treatment with intravenous alteplase (0.9 mg per kilogram of body weight) or placebo. The primary end point was disability at 90 days, dichotomized as a favorable outcome (a score of 0 or 1 on the modified Rankin scale, which has a range of 0 to 6, with 0 indicating no symptoms at all and 6 indicating death) or an unfavorable outcome (a score of 2 to 6 on the modified Rankin scale). The secondary end point was a global outcome analysis of four neurologic and disability scores combined. Safety end points included death, symptomatic intracranial hemorrhage, and other serious adverse events.

Results: We enrolled a total of 821 patients in the study and randomly assigned 418 to the alteplase group and 403 to the placebo group. The median time for the administration of alteplase was 3 hours 59 minutes. More patients had a favorable outcome with alteplase than with placebo (52.4% vs. 45.2%; odds ratio, 1.34; 95% confidence interval [CI], 1.02 to 1.76; P=0.04). In the global analysis, the outcome was also improved with alteplase as compared with placebo (odds ratio, 1.28; 95% CI, 1.00 to 1.65; P<0.05). The incidence of intracranial hemorrhage was higher with alteplase than with placebo (for any intracranial hemorrhage, 27.0% vs. 17.6%; P=0.001; for symptomatic intracranial hemorrhage, 2.4% vs. 0.2%; P=0.008). Mortality did not differ significantly between the alteplase and placebo groups (7.7% and 8.4%, respectively; P=0.68). There was no significant difference in the rate of other serious adverse events.

Conclusions: As compared with placebo, intravenous alteplase administered between 3 and 4.5 hours after the onset of symptoms significantly improved clinical outcomes in patients with acute ischemic stroke; alteplase was more frequently associated with symptomatic intracranial hemorrhage. (ClinicalTrials.gov number, NCT00153036.)

Publication types

  • Clinical Trial, Phase III
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Adult
  • Aged
  • Brain Ischemia / drug therapy
  • Double-Blind Method
  • Drug Administration Schedule
  • Female
  • Fibrinolytic Agents / administration & dosage*
  • Fibrinolytic Agents / adverse effects
  • Humans
  • Infusions, Intravenous
  • Intracranial Hemorrhages / chemically induced
  • Logistic Models
  • Male
  • Middle Aged
  • Odds Ratio
  • Stroke / complications
  • Stroke / drug therapy*
  • Stroke / mortality
  • Time Factors
  • Tissue Plasminogen Activator / administration & dosage*
  • Tissue Plasminogen Activator / adverse effects
  • Treatment Outcome

Substances

  • Fibrinolytic Agents
  • Tissue Plasminogen Activator

Associated data

  • ClinicalTrials.gov/NCT00153036