Small-cap pharmaceuticals to watch: Tyvaso, Axsome, and Exelixis.

Small-cap pharmaceutical stocks are gaining attention as companies approach key clinical trial readouts and regulatory decisions. Terry Smith from Emerald Advisers highlights three companies: United Therapeutics, Axsome, and PTC Therapeutics. United Therapeutics' Tyvaso could double sales with a new drug targeting lung disease, while Axsome's depression treatment has shown promising results in late-stage trials. PTC Therapeutics is working on a treatment for spinal muscular atrophy, which could expand its revenue opportunities.