If this is just a straight up commercial decision by NVS not to develop a "second" MEK, then this could be a great opportunity for ARRY. They will have full rights to a drug with financial support through 3 P3s and numerous expansion P2s. They can either keep the entire drug or re-partner on better terms (likely a decent chunk of cash up front along with US 50% profit split and 15+% royalty ex US).
On the other hand, one always must assume a decision to return a drug is at least partly based on data we do not see.
I think I need to both buy more and sell at the same time :-)