I'm not so sure it's a great time at all. Most alzheimer's drugs have failed dramatically. vTv Therapeutics is the most recent I think. They had a Phase 3 drug trial end early due to futility, and their stock tanked hard. In one day I think it lost 70% of its value.
Alzheimer's drugs have not been successful, but in general it is the best time ever to start a biotech company. Returns in biotech VC the last 5 years are better than tech, more IPO and big M&A (three $8-12B startup acq in last 4-6 months) even with 1/5 the funding of software, tons of great science out there, massive amounts of capital ($4B venture funding to startups in Q1)
As far as I'm aware the majority of failing biotech companies have very broadly targeted Amyloid beta (apparently because they thought it was a good risk tradeoff). A narrow focus on APOE4 could be a wiser strategy. I could even see gene therapy playing a role.
