Effect of the apolipoprotein E epsilon4 allele on the efficacy and tolerability of galantamine in the treatment of Alzheimer's disease.

Objective: To investigate the effect of the apolipoprotein E (ApoE) epsilon4 allele on the efficacy and tolerability of galantamine treatment.

Methods: A total of 202 patients with mild to moderate Alzheimer's disease participated in a 16-week, prospective, multi-center, randomized, double-blind galantamine trial in a Korean population. Patients were assessed at baseline and after 4, 8 and 16 weeks of randomized treatment using the 11-item cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog/11), the Clinician's Interview-Based Impression of Change plus Caregiver Input (CIBIC-plus), the Disability Assessment for Dementia Scale (DAD), the Behavioural Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD) and adverse events. ApoE genotypes were determined for all subjects.

Results: Of the 202 subjects, 115 carried at least one ApoE epsilon4 allele and 87 did not. In both ApoE epsilon4 carriers and ApoE epsilon4 noncarriers, significant improvements were detected relative to baseline on ADAS-cog/11, CIBIC-plus, DAD and BEHAVE-AD. ApoE epsilon4 noncarriers showed better improvement in mean total BEHAVE-AD score and mean psychosis (delusions and hallucinations) subscale score than ApoE epsilon4 carriers. The incidence of weight loss was significantly higher in ApoE epsilon4 carriers (n = 11; 9.6%) than in ApoE epsilon4 noncarriers (n = 1; 1.2%) during this 16-week study, even though 92% of patients who complained of weight loss completed this 16-week trial successfully.

Conclusion: ApoE epsilon4 genotype does not affect galantamine-related improvements in cognition, global rating, function and behavior. Longer prospective studies with larger patient populations are required to confirm these new findings.