LLYs drug inhibited gamma secretase. I guess Merck are after beta secretase, thought to be more specific. [ This amyloid is split off (for some reason) from the middle of a larger precursor protein (APP), and there are two enzymes that make the cuts to release it: gamma-secretase and beta-secretase. Shutting down one or both of those has long been seen as the most direct route to keeping amyloid from accumulating, and compounds that do this have been sought for at least twenty years now.] http://pipeline.corante.com/archives/2010/08/18/lillys_gamma_secretase_inhibitor_for_alzheimers_worse_than_nothing.php
I dont think they would even use the word secretase after LLYs spectacular crash and burn with gamma. Not an expert on these drugs so correct me if I am wrong please.