Memantine and Alzheimer's disease

Memantine, a drug approved for the treatment of Alzheimer disease, appears safe and effective in patients with moderate to severe cases of the condition, according to a study in the January issue of Archives of Neurology.

Millions of people worldwide have Alzheimer disease (AD), a progressive neurodegenerative disorder, according to background information in the article. Various chemical and other processes in the brain may contribute to the development of the condition. Memantine appears to act on one of those pathways, which involves the neurotransmitter glutamate, the authors report. The drug was approved in the United States in 2003 and also is available in the European Union and Australia.

Barry Reisberg, M.D., from the New York University School of Medicine, and colleagues conducted a 24-week open-label extension trial. In this type of trial, participants who had previously been part of a double-blind study--where some were taking an active drug and some were taking a placebo--were all given the same amount of the active drug. For this study, 175 patients with moderate to severe AD who completed the previous 28-week study received 20 mg of memantine daily for an additional 24 weeks.

The authors report that during the study, cognitive tests, reports from caregivers and observations by clinicians all indicated that memantine was beneficial to AD patients. "The benefits of memantine seen in the double-blind phase were again observed when patients treated with placebo were switched to memantine treatment in the open extension," they write. "For the patients who were randomized to memantine treatment during the double-blind phase, these clinically relevant benefits also appeared to be maintained in sum." The completion rate for the extension phase was high (78 percent) and the adverse event profile for memantine was similar to that observed in the double-blind study.