Focus On Exelon For Alzheimer's Disease

Earlier this month, Novartis' second-generation acetylcholinsteraseinhibitor was approved in its first market, Switzerland, for the treatment of mild-to-moderate Alzheimer's disease (Marketletter August 11).

The drug will reach the market later this year as the second drug in this new generation of ACHEIs, after Pfizer/Eisai's Aricept (donepezil). Both drugs offer significant efficacy and tolerability advantages over the only other approved ACHEI for this indication, Warner-Lambert's Cognex (tacrine), which will now no longer be actively promoted.

As the first two drugs to reach the market in a sector which had previously been largely barren of drug treatments, both Aricept and Exelon are near-guaranteed to make significant sales, with analysts' estimates for both drugs in the $500 million to $1 billion-plus range. But is there anything to choose between them? Novartis claims that Exelon is the only Alzheimer's drug to have been shown to improve activities of daily living (while placebo patients experienced a decline), and that it is also the only drug which has generated efficacy data from European trials.