Memantine, NMDA-R antagonist, is approved for the treatment of moderate-to-severe Alzheimer's disease (MMSE< 20) (AD). The purpose of this study was to evaluate the efficacy and safety of memantine when used in routine clinical practice.

The 6-months, observational, open-label, multicentre study in 202 specialist centers in Greece evaluated the efficacy of memantine using the MMSE and Instrumental Activities of Daily Living (IADL) scale at baseline, 3 and 6 months. Safety was evaluated by spontaneously reported adverse events (AEs). Statistical efficacy analyses were performed in the Intent-To-Treat (ITT) (at least one post-baseline evaluation) and Per Protocol (PP) datasets (evaluations at both 3 and 6 months).

The study included 2570 AD patients (age: 74.8±6.8, 54.6% women, baseline MMSE score: 18.0±5.0). 34.2% had received previous treatment with acetylocholinesterase inhibitors (AChEIs), while for 65.8% memantine was the first treatment option. At baseline 91.5% were prescribed memantine as monotherapy, the remainder also received AChEIs. During the 6 months of the study, 80.9% continued memantine monotherapy. MMSE score was significantly improved from baseline at 3 (17.9±5.1 vs 19.2±5.0, p< 0.001, repeated measures analysis of variance Hotelling's test, ITT) and 6 months (17.9±5.1 vs 19.7±5.1). At 6 months, 67% of the ITT population had improved their MMSE score and 18.6% had no change. 19 patients (0.7%) terminated the therapy prematurely due to AEs. AEs were reported in 182 (7.1%) patients: the most common was dizziness (1.45%). 8 (0.3%) of the AEs were severe.

These results in naturalistic settings support the excellent efficacy and tolerability profile of memantine.