RESUMO
In order to confirm the efficacy and safety of posatirelin (L-pyro-2-aminoadipyl-L-leucyl-L-prolinamide), a synthetic peptide having cholinergic, catecholaminergic and neurotrophic activities, a multicentre, double-blind, controlled study versus placebo was planned in elderly patients suffering from Alzheimer's disease and vascular dementia, according to National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) and National Institute of Neurological Disorders and Stroke/Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) criteria, respectively. The trial consisted of a 2-week run-in phase with placebo administered once a day orally, followed by a double-blind period of 3 months, with posatirelin or placebo administered once a day intramuscularly. Efficacy was assessed using the Gottfries-Bråne-Steen (GBS) Rating Scale (primary variable) and the Rey Memory Test (secondary variable). Laboratory tests, vital signs and adverse events were monitored. A total of 360 patients were randomized, the intent-to-treat sample (ITT) being made up of 357 patients and the per protocol sample (PP) of 260 patients. Both pragmatic and explanatory analyses showed significant differences between treatment groups in the GBS Rating Scale and the Rey Memory Test, with no difference in the two types of dementia. No difference between treatments was observed in safety variables, the incidence of adverse events in the posatirelin group being 7.3%. The study confirms previous results showing that treatment with posatirelin can improve cognitive and functional abilities of patients suffering from degenerative or vascular dementia.