Ummm. He made a fortune because he got the news of the victory before anybody else. The later Rothschild is also quoted when asked how he made his money "By buying too late and selling too soon."
This share price for AVXL is a great deal if, and only if, one of the drug trials succeeds.
Having said that, I do expect a small rally after the end of the year because I do think this is mostly tax selling and that selling pressure will be over. There are other investors that will see that and then buy in when it is safer.