I think the Lilly/Elan secretase inhibitors are destined to be interesting failures. They are first generation compounds with too big a side effect profile and they are targeting mild/moderate disease at which point the amyloid cascade is too far advanced for upstream intervention to make a difference.
I'm under the belief that Elan's stock price at this point has nothing to do with its drugs but the price reflects the concern people have with its balance sheet.
If they were in any other business they would have been shot and buried a long time ago. It IS the strength of their drugs that gives them a $5 price and until the worlds financing gets in line they'll be hurting.