Aktuelle Neurologie 2009; 36 - P622
DOI: 10.1055/s-0029-1238715

SWAP: the safety and tolerability of switching from donepezil tablets to rivastigmine transdermal patch in Alzheimer's disease

G Alva 1, M Farlow 1, C Sadowsky 1, S Brennan 1
  • 1Costa Mesa, Indianapolis, Fort Lauderdale, East Hanover, USA

Introduction: Switching medications is common for many reasons, particularly safety/tolerability issues. The SWAP study (SWitch from Aricept to Patch) evaluates the safety/tolerability of two drug switching paradigms in AD: switching from donepezil to rivastigmine patch immediately versus after a 7-day wash-out. This study also evaluates the safety/tolerability of rivastigmine patch-memantine therapy.

Hypothesis: Switching from donepezil to rivastigmine patch is safe and tolerable with no statistical differences in adverse event rates between immediate switch and a 7-day wash-out.

Methods: A 5-week, open-label study with a 20-week extension. Patients were randomized to an immediate switch from donepezil (5–10mg/day) to 5cm2 patch, or a switch following 7-day withdrawal of donepezil. Patients entering the study on concomitant memantine continued treatment. Primary evaluations included safety and tolerability.

Results: 262 AD patients were enrolled/243 completed. Primary reason for discontinuation was AE and withdrawal of consent (both 2.7%). Mean age was 78 years, with 58% female and 87% Caucasian. All received stable donepezil for ≥6 months, with 50% on stable memantine combination treatment. In patients randomized to immediate switch the total AEs were 34 (26%) compared to delayed switch with 42 (33%). Most common AEs in the immediate switch group were nausea (5 patients 3.8%), decreased appetite (4 patients 2.3%) and fatigue (3 patients 2.3%). For those in the delayed switch group; constipation (5 patients 3.9%), agitation (4 patients 3.1%) and confused state (3 patients 2.4%). All other AEs in both groups were random and transient (occurred in <1.6% of patients).

Conclusion: The results suggest that when switching from donepezil or donepezil-memantine combination therapy to rivastigmine patch there is little difference in an immediate switch or delayed switch with both regimens appearing very well tolerated.