A multicenter prospective double-blind placebo-controlled study was carried out in 62 patients with hemisphere ischemic stroke of atherothrombotic or cardiothrombotic character. Thirty-two patients, a main group, received intramuscular injections of cortexin, a domestic drug, in dosage 20 mg daily during 10 days from the first 6 hours from the development of symptoms of stroke, and 30 patients, a control group, received basic treatment and intramuscular injections of placebo in dosage 20 mg daily during 10 days. Patient's state was assessed before treatment and on 3rd, 7th, 11th and 28th days using the NIHSS scale for assessment of disease severity, intensity of focal neurologic deficit and dynamics of clinical parameters and the modified Rankin scale and Barthel index as a functional outcome measures. The data obtained suggest an efficacy of cortexin in the treatment of patients with acute ischemic stroke as compared to placebo. Safety of the drug was confirmed in the study.