Cerebrolysin for Acute Stroke: Large Trial Shows No Overall Benefit but a Signal in Severe Cases

Double-blind, placebo-controlled randomized clinical trial across Asian centers. Patients with acute ischemic hemispheric stroke were randomized within 12 hours of symptom onset to receive either Cerebrolysin 30 mL daily or saline placebo as IV infusion for 10 days, plus aspirin 100 mg daily. Follow-up was 90 days. Primary endpoint was a combined global test of modified Rankin Scale, Barthel Index, and NIHSS.

Acute ischemic stroke remains devastating, and effective neuroprotective treatments beyond clot removal are limited. While Cerebrolysin didn't help the overall stroke population in this trial, the signal in severely affected patients — particularly the halved mortality rate — suggests the peptide mixture may have a role specifically in the most serious strokes, where brain damage is extensive and neuroprotection matters most.

The search for effective neuroprotectants after stroke has been called the 'graveyard of clinical trials' — dozens of promising agents have failed in large studies. Cerebrolysin's overall neutral result fits this pattern, but the mortality signal in severe strokes is one of the more compelling subgroup findings in the field. It led to subsequent trials specifically targeting severe stroke patients, keeping Cerebrolysin in the neuroprotection conversation when most competitors had been abandoned.

The primary endpoint was negative — Cerebrolysin did not outperform placebo in the overall population. The favorable findings in severe stroke patients came from a post hoc subgroup analysis, which is hypothesis-generating, not confirmatory. Treatment was given within 12 hours of onset, which may miss the earliest therapeutic window. The study was conducted only in Asian populations.