Third International Stroke Trial "IST-3"


Phase 3 Results

Trial Description

To determine whether administration of recombinant tissue plasminogen activator (r-tPA) within 6 hours of ischemic stroke increases the proportion of independent survivors at 6 months.


Trial Design

International, multicenter, prospective, randomized, open, blinded endpoint (PROBE) design controlled trial.

Patient Involvement

All patients will be given a pre-randomization CT to assess eligibility and rule out hemorrhage. MRI is permissible, but strongly discouraged. Eligible patients will be randomized to receive either IV rt-PA (0.9mg/kg; max 90 mg), 10% of which would be infused over 1 minute, and the remainder over 60 min, or placebo, to be delivered in the same manner. Any patients who develop symptoms of hemorrhage are to receive urgent CT imaging, bloodwork, and emergency care. All patients will receive a CT at 24 hours to exclude complications. Antithrombotics are disallowed during the first 24 hours. After 24 hrs, all patients will be considered for long-term aspirin or other antiplatelet therapy. Follow-up will take place at 7 days, discharge, or transfer, whichever is first; and again at 6 and 18 months.


Type Measure Time Frame Safety Issue
Primary Independence, based on modified Rankin Scale (MRS) score, and mortality at 6 months
Secondary Incidences of mortality, intracranial hemorrhage, extracranial hemorrhage, and recurrent ischemic stroke at 7 days; all deaths, vascular deaths, MRS and EuroQol scores, and places of residence at 6 and 18 months.


UK Medical Research Council, the Health Foundation, the Stroke Association (UK), the Norwegian Research Council, the Government of Poland, AFA insurances (Sweden), and the Australian Heart Foundation.