The study was conducted in 3 Russian centers (Moscow, St. Petersburg and Nizhniy Novgorod). The total sample included 110 patients whose mental state met the definition of <<mild cognitive impairment>> (MCI). Patient's status was assessed with widely used scales (MMSE, GDS, CDR etc) and a battery of neuropsychological tests. Genotyping for the APOE polymorphism was performed as well. Patients were stratified into 2 comparable groups in compliance with the specifics of therapy: 55 patients were treated with cerebrolysin and 55 - with cavinton. The superiority of cerebrolysin over cavinton in slowing down of the cognitive deficit progression and delaying the time or transition of patients to the diagnostic category of Alzheimer's disease was demonstrated. Cerebrolysin was particularly effective in MCI patients with the ApoE(+) genotype, i.e. in those with higher risk for Alzheimer's disease. Adverse effects during the treatment were rare in both groups.