ARIA’s drug (in collaboration with MRK) received a negative vote from its Ad Comm panel with 13-1 voting against its approval. It will therefore be receiving a CRL in June. I exited my position last week – after the briefing documents were released. This is not a best practice.
In general I think the best way to trade the Ad Comm meetings is to look for an entry point about 4 weeks out and exit the position when a reasonable gain has been made (or a maximum loss) or when there are three days left to the meeting. The briefing documents can produce rapid moves in the price and I think it is best not to be exposed to them.
ARIA was a bit different from most of the smaller biotechs I look at in that this Ad Comm meeting was not make-or-break for the company. Its future value is really driven by its other developmental drug, Ponatinib. in fact, in the after-hours its stock is barely taking any hit from the adverse vote.
I have written some thoughts on trading Ad Comm meetings over at Seeking Alpha.