Memantine in moderate-to-severe Alzheimer’s Disease
This study published in the New England Journal of Medicine reports on the efficacy of memantine in patients suffering from moderate to severe Alzheimer dementia.
Memantine proved to be significantly superior to placebo on three independent levels:
- Acitivities of daily living
- Cognitive performance
- Clinical global impression
In addition, memantine reduces caregiver time by 52 hours a month.
Response rates were two to three times higher in the memantine group compared to placebo and the side effects rates were comparable in both groups.
Methods
The US study conducted by Reisberg et al. is a 6-month, double-blind randomized 2-arm multi-center study with an optional open-label extension. 252 out-patients diagnosed with Alzheimer’s disease took part in this study. The inclusion criteria required the patients to be over the age of 50 and their MMSE had to be between 3 and 14. The average MMSE was 7.9 and the average age was 76 years. The patients were randomized to receive either 20 mg memantine daily or placebo double blind for 28 weeks.
Results
 Figure 1: Significant Benefit on Cognition |
 Figure 2: Significant Benefit of Memantine in Activities of Daily Living |
 Figure 3: Significant Benefit of Memantine in Clinical Global Impression |
The memantine-treated patients showed significantly less decline in cognitive performance, measured by the Severe Impairment Battery (SIB), than the placebo group (Figure 1). Activities of daily living, measured by ADCS-ADLsev, were also substantially less impaired in the memantine group than in the placebo group (Figure 2). In addition, researchers observed less deterioration of clinical global impression, measured by the CIBICplus again significantly favoring memantine (Figure 3). Patients receiving memantine also required considerably less caregiver time – 52 hours per month – than subjects receiving placebo, as assessed by the Resource Utilization in Dementia (RUD) scale (Wimo et al. 2003).
The superior treatment results were achieved regardless of severity staging. Both subgroups of Alzheimer patients with moderate dementia and severe dementia showed an advantage regarding all outcome measures.
Often reported adverse events were barely more frequent in the memantine group than in the placebo group. Medication was discontinued, due to adverse effects, almost twice as often (22 patients vs.13) in the placebo group as in the memantine group. In general, the authors concluded that “the tolerability of memantine in this study was found to be excellent.”
