On the news of favorable recommendation from FDA Advisory Committee for once-a-day Breo which both THRX and GSK expects to succeed GSK's off patent twice-a-day Advair with $8 billion sales last yr, THRX is up 34%. That is an increase in market cap of about $850M. FDA's decision for approval or not is schedule for 5/12 in a few weeks. GSK already owns 27% of THRX and it is widely speculated that GSK with buy THRX upon approval. On the other hand, the news of VRTX's positive Phase II data on VRTX's yet to be named CB drug VX-661, VRTX popped 61% in a day. That is an increase of $7.1 billion in market cap. The drug still have to go through Phase III and if successful the FDA, both of which are a few years out Analysts estimated 30,000 US patients and 70,000 WW. I m feeling investors who bid up VRTX maybe overly optimistic. I m long THRX and short VRTX.