KIT and gastrointestinal stromal tumor: Preclinical models have shown that expression of ETV1, a member of the ETS family of transcription factors, is necessary for GIST tumor growth, and KIT activation promotes expression and stability of ETV1.101,102 Combined inhibition of KIT and ETV1 with imatinib and binimetinib (MEK-162), respectively, showed synergistic effect in in vitro and in vivo models.103 Phase I and II (NCT01991379) testing found this combination to be safe and well-tolerated in treatment-naïve patients.104,105 The ORR was 69%, and median PFS was 30 months.105