By: Ed Susman

VANCOUVER, BRITISH COLUMBIA, CANADA – A higher dose of the rivastigmine-containing patch appears to slow the progression of mild to moderate Alzheimer’s disease better than treatment with the standard-dose patch, researchers said at the 2012 Alzheimer’s Association International Conference.

“We observed that fewer patients discontinued the higher dose 13.3 mg/24 hour patch and those on the 9.5 mg/24-hour patch, suggesting better efficacy without increasing adverse events,” said Sandra Black, MD, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario.

In several measurements of effect, the higher dose patch was consistently exhibited superior effectiveness than the standard dose patch, which is currently approved for treatment of mild to moderate Alzheimer’s disease.

For example, the least square mean analysis showed that the reduction in the Alzheimer’s Disease Cooperative Study-Activities of Daily Living score was 4 points with the 13.3-mg patch but was 6 points with the 9.5-mg patch (P =.028 at 48 months). The difference in effect was seen across all analyses, according to Dr. Black. Significant differences were also observed at week 16, week 24, and week 32.

Although adverse events occurred more frequently in the higher dose patch — 210 events among 280 patients on the high-dose patch compared with193 events in 283 patients on the low-dose patch — she noted that discontinuations caused by adverse events occurred in 9.6% of the high-dose group versus 12.7% of the low-dose group.

“This suggests that the higher dose would enable more patients to achieve therapeutic doses and therefore achieve optimal therapeutic outcomes,” said Dr. Black.

Patients in the study had been diagnosed with Alzheimer’s disease for about 4 years when they were enrolled in the study.

Dr. Black explained that in the clinical trials that were conducted to approve rivastigmine as a transdermal patch, the higher dose patches were shelved because they tended to produce higher adverse events.

Funding for this study was provided by Novartis Pharma AG.

- MFP Wire Services
- 07-26-2012