How Big of a Deal Is Axsome Therapeutics' New Depression Drug?

Major single-day swings are a common occurrence in the biotech sector, as strong late-stage clinical results can send a stock surging. That's exactly what happened on Dec. 16 when Axsome Therapeutics (NASDAQ: AXSM), a $2.8 billion clinical-stage biotech stock, rose by 70.6% over the course of the day in response to new results for its late-stage depression drug.