BLU-285 is a dual inhibitor of KIT receptor and platelet-derived growth factor receptor α (PDGFRα) tyrosine kinases with activating loop mutations (IC
50s = 0.27 and 0.24 nM for KIT
D816V and PDGFRα
D842V, respectively).
1 It is >150-fold selective for KIT
D816V and PDGFRα
D842V over a kinase panel at a concentration of 3 μM. BLU-285 also has activity against a panel of KIT and PDGFRα loop mutants identified in patients with gastrointestinal stromal tumors (GISTs; IC
50s = <100 nM). It inhibits growth of cancer cell lines containing wild-type and mutant KIT and PDGFRα, demonstrating increased potency in cell lines expressing KIT and PDGFRα with activating loop mutations. BLU-285 (0.3-30 mg/kg) reduces tumor volume in a P815 KIT
D814Y mastocytoma allograft mouse model and a GIST patient-derived mouse xenograft model in a dose-dependent manner. Formulations containing BLU-285 have been used to treat KIT- and PDGFRα-driven malignancies.