Update on Alzheimer drugs (donepezil)

Several clinical trials have been conducted over a period of many years reporting the benefits of donepezil for Alzheimer disease (AD) patients.

Randomized, double-blind, placebo-controlled stud-ies of 3-6 months' duration have demonstrated significant benefits for 5mg/D and 10 mg/D of donepezil compared with placebo. The results include benefits for cognition, activities of daily living, and abnormal behaviors associated with AD. The benefits are independently detectable by clinicians based upon direct patient assessment with input from a caregiver. Populations studied include mild-to-moderate AD patients, moderate-to-severe AD patients, nursing home patients, and outpatients. Open label studies that took place after the double-blind phase and 1-year double-blind, placebo-controlled trials demonstrated that benefits persist for more than a year. Adverse event (AE) profiles, generated in studies that used a 1-week forced dose titration, show a low incidence of primarily cholinegic AEs such as nausea and diarrhea. There are no significant laboratory AEs or drug interactions. Recent studies have assessed the benefits of donepezil inpatients with ischemic vascular dementia, mild cognitive impairment, and other cognitive disorders.

Donepezil benefits AD patients by improving, stabilizing, or retarding decline of the cognitive, functional, and possibly behavioral features of the disease. The duration of benefits is not known but extends beyond 1 year. The drug is safe and well tolerated.