Background and purpose: High-dose human albumin (ALB) is robustly neuroprotective in rodent stroke models. A phase I dose-escalation study was conducted to assess the safety of ALB therapy in ischemic stroke. We analyzed the data for preliminary evidence of treatment efficacy.
Methods: Eighty-two subjects with acute ischemic stroke (NIH Stroke Scale [NIHSS] of 6 or above) received 25% ALB beginning within 16 hours of stroke onset. Six successive ALB dose tiers were assessed (range, 0.34 to 2.05 g/kg). Forty-two patients also received standard-of-care intravenous tissue plasminogen activator (tPA). Efficacy outcomes were determined at 3 months. We compared the highest three, putatively therapeutic ALB dose tiers (1.37 to 2.05 g/kg) with the lowest three, presumed subtherapeutic doses (0.34 to 1.03 g/kg) and with historical cohort data derived from the NINDS rt-PA Stroke Study.
Results: After adjusting for the tPA effect, the probability of good outcome (defined as modified Rankin Scale 0 to 1 or NIH Stroke Scale 0 to 1 at 3 months) at the highest three ALB doses was 81% greater than in the lower dose-tiers (relative risk [RR], 1.81; 95% confidence interval [CI], 1.11 to 2.94) and was 95% greater than in the comparable NINDS rt-PA Stroke Study cohort (RR, 1.95; 95% CI, 1.47 to 2.57). The tPA-treated subjects who received higher-dose ALB were three times more likely to achieve a good outcome than subjects receiving lower-dose ALB, suggesting a positive synergistic effect between ALB and tPA.
Conclusions: Our data suggest that high-dose ALB therapy may be neuroprotective after ischemic stroke. These results have led to a multicenter, randomized, placebo-controlled efficacy trial of ALB in acute ischemic stroke-the ALIAS Phase III Trial.