ONCE:
Today seemed like a good day to go short (my first ever who knows maybe my last ever too :-)). Just a small short position and I bought a few (very small) # of puts yesterday (spread is too big to get a decent amount).
There can be a few good things (from ONCE's perspective) from their Hemophilia A program (Higher factor levels, more consistent individual and within cohort #'s) but with the appreciation in stock price, I think a good part of that seems to be priced in. Probably if BMRN has a serious setback would be a bigger plus for their A program.
On Hemophilia B (which they only have a share of with PFE collaboration) they now seem to be lacking an advantage over Uniqure (time wise and potentially efficacy wise as well). Anyway, I don't intend to hold my short position that long. I see playing QURE vs ONCE Hemophilia B as an argument much further down the road.
The earlier stage pipeline is actually what I find most intriguing from a long investment standpoint (Pompe, CLN2 and Huntington's) and why I would considering going long at much, much lower prices since they are very early still.