Memantine in the treatment of mild to moderate dementia syndrome. A double-blind placebo-controlled study

Abstract

The efficacy and the tolerability of memantine (1-amino-3,5-dimethyladamantane hydrochloride, Akatinol Memantine, CAS 41100-52-1) were investigated in patients with mild to moderate dementia syndrome in a randomized two-centre placebo-controlled clinical study. The test substance was administered at a dose of 10 mg/d from day 1 to day 3 and then at a dose of 2 x 10 mg/d from day 4 to the end of treatment after 42 days. Altogether, 88 patients were recruited to the study; their average age was 71.5 years. The efficacy of memantine was judged on the basis of the baseline/6 week differences in the total sum scores of the Clinical Assessment Geriatric Scale (SCAG), the Gottfries-Bräne-Steen Scale (GBS), the SCAG and GBS subscales and the global assessment of the change in the patient's condition. The effects of memantine on performance were studied with the aid of psychomotor tests and a behaviour investigation relating to activities of daily living (ADL). The tolerability of memantine was assessed on the basis of the doctor's global assessment and of entries on structured documentation forms (DOTES/TWIS). Further safety parameters--in the form of clinicochemical tests and measurements of blood pressure and heart rate--were also monitored during the study. On both the psychopathological measurement level (SCAG, global assessment of the change in the patient's condition) and the behavioural level (GBS), confirmatory statistical analysis brought to light significant differences between memantine and placebo (p less than or equal to 0.05), these differences showing a superiority of memantine. The tolerability of memantine was good in the main. The observed adverse reactions were not serious and, except in 3 patients, were rated as causing little or no impairment. The present clinical study demonstrates the efficacy of memantine in patients suffering from mostly moderate dementia syndrome. Clinical and statistically relevant improvements in the dementia-induced disturbances were found on the both the psychopathological level (SCAG, CGI) and the behavioural level (GBS). On the performance level also, the ADL behaviour investigation detected a highly significant improvement in the quality of performance of instrumented activities of daily living under memantine. Also the time taken to carry out these tasks was significantly reduced in comparison with placebo.