Amuvatinib shows in vitro inhibitory activity against multiple human tyrosine kinases including mutant KIT and PDGFRα and in vivo activity in human xenograft models in mice. Amuvatinib is also active as a DNA repair protein Rad51 inhibitor following chemotherapy. In this study, the amuvatinib DPC formulation was well tolerated up to 1,500 mg/day. While exposures were low and variable, a transient response in a refractory GIST patient warrants further investigation into single-agent amuvatinib in refractory GIST.