Safety and tolerability of the rivastigmine patch: results of a 28-week open-label extension

The primary objective of the open-label extension was to evaluate the long-term safety and tolerability of a transdermal rivastigmine patch up to 1 year, as a novel approach to treatment in Alzheimer disease. This was a 28-week extension to a 24-week, double-blind, double-dummy, placebo-controlled, and active-controlled study evaluating rivastigmine patches [9.5 mg/24 h (10 cm2) and 17.4 mg/24 h (20 cm2)] and oral capsules (3 to 6 mg twice-daily). Patients entering the extension were switched directly to 9.5 mg/ 24 h rivastigmine patch and increased to 17.4 mg/24 h patch, irrespective of their double-blind study treatment. Primary measures included safety and tolerability assessments, including adverse events and serious adverse events. Of 1195 patients randomized to treatment, 870 (72.8%) completed the double-blind study and entered the open-label extension. During weeks 1 to 4 of the extension, 9.5 mg/24 h rivastigmine patch was well tolerated overall by patients formerly randomized to rivastigmine capsule or patch groups: < or =2.5% reported nausea and < or =1.9% reported vomiting. No unexpected safety issues arose, and skin tolerability was good; similar to the double-blind study. During the 28-week, open-label extension phase, the patch seemed to be well tolerated with a favorable safety profile.