I wouldn't discount a complementary role for a partner -- I mentioned this with a possible AVXL / SAVA merger earlier, but CRTX may make more sense. It'll take a while though because while both drugs are safe on their own, a trial would be needed to study the safety and efficacy when taken together.
My concern is that the FDA won't want to approve more than 2 Alzheimer's drugs within a year. Aducanumab is a placeholder until something better comes along, so it's a race to see who gets to replace it. Anavex is probably on a slower track for Alzheimer's, which is why I like that Dr. Missling is also focusing on Rett and Parkinson's. If/when it gets approved for Alzheimer's, it'll boil down to the data and which drug is more effective between AVXL, CRTX and SAVA