Efficacy and Safety of Donepezil 23 mg versus Donepezil 10 mg for Moderate-to-Severe Alzheimer’s Disease: A Subgroup Analysis in Patients Already Taking or Not Taking Concomitant Memantine
Dementia and Geriatric Cognitive Disorders, 05/15/2012
Clinical Article
Doody RS et al. – In this population, concomitant memantine use did not alter the response profile of donepezil 23 vs. 10 mg/day. Donepezil 23 mg was generally safe and well tolerated among patients receiving donepezil alone and among patients receiving a combination of donepezil and memantine therapy.
Methods- Prespecified analysis of data from a 24-week, randomized, double-blind trial.
- Patients were randomized to donepezil doses (23 vs. 10 mg/day) and stratified by concomitant memantine use (yes or no).
- Efficacy and safety were assessed for each donepezil dose in subgroups taking or not taking concomitant memantine.
- At week 24, donepezil 23 mg/day provided significant cognitive benefits over 10 mg/day (p < 0.01) on the Severe Impairment Battery, with or without concomitant memantine (ANCOVA adjusted for baseline score, country and treatment).
- The higher dose showed no benefit on the global function, Mini-Mental State Examination or activities of daily living measures in either memantine subgroup.
- Rates of treatment-emergent adverse events (AEs) were higher for donepezil 23 mg/day with memantine (80.7%) than 23 mg/day without memantine (69.7%) or 10 mg/day with/without memantine (66.7/62.0%); across all treatment groups, most events were mild/moderate in severity.
- Individual rates of serious AEs were low (<1.0%), regardless of concomitant memantine use.



