Nuwellis (NUWE) shares were more than 160% higher pre-bell Tuesday following a 3.2% loss in the previous session.
BiomX (PHGE) stock was up 60% after Monday's gain.
Namib Minerals (NAMM) shares were 16% higher, extending Monday's rally.
General Motors (GM) stock was up 5% after the company reported Q4 adjusted earnings that topped analysts' estimates.