Axsome shares rocket up on a surprise win for late-stage Alzheimer’s agitation study — but this is no easy layup

Shares of Axsome Therapeutics $AXSM shot up Monday morning on the surprise news that its lead drug scored statistically significant results for Alzheimer’s agitation, a relatively green field in drug R&D, in what’s billed as a pivotal Phase II/III trial. But the company will have plenty of high-risk work to do before it can expect an FDA approval.