From what I hear anecdotally, MRK is seeing improvement in Alzheimer pts in the MK-8931 trial (there is no placebo effect like in depression or anxiety conditions in AD trials, so if pts are improving it implies drug efficacy). This is consistent with MRK management placing a top priority on the MK-8931 program as reflected in the 10/1//13 announcement regarding redesign of MRK corporate operating model:
"Refocused and Prioritized Research and Development
Merck has prioritized its R&D efforts to focus on candidates capable of providing unambiguous, promotable advantages to patients and payers.
This focus will include programs such as the company’s anti-PD-1 immunotherapy program in oncology, BACE for Alzheimer’s disease (MK-8931), its next generation HCV program and V503, the company’s 9-valent HPV vaccine. "
The MK-8931 royalty stream has not yet been incorporated into the LGND financial model, but with accumulating evidence of 8931 efficacy/safety, the financial impact of this mega-blockbuster drug will become part of the LGND picture sooner than later IMO.