Hypothesis
Adding endovascular therapy after intravenous t-PA would increase functional independence at 90 days in moderate-to-severe acute ischemic stroke, compared with t-PA alone.
What failed
The trial was stopped early for futility after 656 patients. Functional independence (modified Rankin 0–2) at 90 days was 40.8% vs 38.7% (adjusted difference 1.5 points, 95% CI −6.1 to 9.1), with similar mortality and hemorrhage.
Broken assumption
Adding endovascular clot removal after intravenous t-PA improves functional independence in this patient population.
- Stopped early for
- futility
Why
No significant benefit of the combined approach over t-PA alone in this trial, in either predefined stroke-severity subgroup; safety was similar.
From the published paper: Broderick JP, Palesch YY, Demchuk AM, et al. (IMS III). N Engl J Med, 2013. NCT00359424 ↗