There's at least one ethical puzzle here:

Assuming you're a 'scientist' (in this instance simply meaning someone conversant with the science who can read / understand studies) who sees a biotech company that's based its main product on what you see as 'questionable' work...

1... is it ethical to 'short’ stocks of that company, and

2... once you've purchased the short (and so can gain on that company's stock price collapse) is it ethical to 'go public'?

Personally, I'm fine with #1 (see an opportunity...) but find #2 troublesome.

Oh, and, yeah, it's becoming more and more clear that amyloid doesn't have a causative effect for elder onset AD. However, it most probably does have a causative effect for early onset as the known associated SNPs are both involved with amyloid production.

I see there’s an early onset AD trial completed at clinicaltrials.gov testing both Gantenerumab and Solanezumab (amyloid monoclonal antibodies). Unfortunately results seem to be mixed, which suggests that even early onset, which is associated with amyloid-related SNPs, has more complex causation than ‘too much amyloid’. It’s biology where nothing is simple. Sigh.