regardless of the company's performance, look at the general market. Things are really ugly right now. If I were you, I would either short something or get my money out. This is definitely not bull time.
We all need to do the "DD" as noted. One other point not brought up is that many will sell on positive news, we may be seeing the resulting dip. I have found this stock will come back nicely. Remember, GSK has a huge number of shares invested in this company too...the last I saw.