A six‐month double‐blind, randomized, placebo‐controlled study of a transdermal patch in Alzheimer's disease–– rivastigmine patch versus capsule

Abstract

Objectives: To compare the efficacy, safety and tolerability of a novel rivastigmine transdermal patch with conventional rivastigmine capsules and placebo in patients with Alzheimer's disease (AD). Methods: In this 24‐week, multicenter, double‐blind, double‐dummy, placebo‐ and active‐controlled trial, patients with probable AD were randomized to one of four treatment groups: 12 mg/day rivastigmine capsules; 10 cm 2 (9.5 mg/24 h) rivastigmine patch; 20 cm 2 (17.4 mg/24 h) rivastigmine patch; or placebo. Primary efficacy measures were the Alzheimer's Disease Assessment Scale—Cognitive subscale (ADAS‐Cog) and Alzheimer's Disease Cooperative Study––Clinical Global Impression of Change (ADCS‐CGIC). Results: One thousand one hundred and ninety five AD patients from 21 countries participated in the study. Treatment differences (vs placebo) on the ADAS‐Cog at Week 24 in 10 cm 2 patch, 20 cm 2 patch and capsule groups were 1.6 (p = 0.005), 2.6 (p < 0.001) and 1.6 (p = 0.003). Treatment differences on the ADCS‐CGIC were 0.3 (p = 0.01), 0.2 (p = 0.054) and 0.3 (p = 0.009). Comparison between the 10 cm 2 patch and the capsule revealed non‐inferiority. Rates of nausea in the 10 cm 2 patch and capsule groups were 7.2% and 23.1%, respectively; rates of vomiting were 6.2% and 17.0%, respectively. Moderate or severe skin irritation occurred in ≤10% patients across the four patch sizes (5, 10, 15 and 20 cm 2). Conclusions: The target dose of 10 cm 2 rivastigmine patch provides efficacy similar to the highest doses of capsules with a superior tolerability profile. The transdermal patch with rivastigmine may offer convenience important to many caregivers and patients. Copyright © 2007 John Wiley & Sons, Ltd.