Dimebon and Medivation (MDVN): A competitor indeed. Dimebon may be a "nonselective" antihistamine, but that nonselectivity includes NMDA and CA channel modulation as well as apparent beta-amyloid blocking effects, it would blow aricept out of the water, if medivation plays it's cards right.
Instead of working from scratch to find a CALHM-1 modulator, Medivation may already have one ready for a P3.
That said, a swing of 6 ADAS points may be stat sig, but means little in the real world and is only 2 points more than the ADAS differences for Aricept if memory serves.