The study will include an initial Phase 1 portion to determine the maximum tolerated dose (MTD) and/or recommended Phase 2 dose (RP2D) of BLU-945 as monotherapy (initially in a QD regimen with the option to evaluate BID dosing, if supported by emerging PK and safety data), as well as an additional dose-escalation portion to determine the RP2D of BLU-945 in combination with osimertinib. The BLU-945 monotherapy Phase 2 expansion groups will consist of patients with tumors harboring specific mutation profiles (EGFR T790M and C797S mutation [Group 1]; EGFR T790M but not C797S [Group 2]; or EGFR C797S but not T790M [Group 3]). The BLU-945 with osimertinib Phase 2 expansion (Group 4) will include approximately 24 evaluable patients, with at least 12 slots reserved for patients with EGFR T790M and C797S mutation.
This is a Phase 1/2, open-label, first-in-human (FIH) study designed to evaluate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and anticancer activity of BLU-945, a selective EGFR inhibitor, as monotherapy or in combination with osimertinib.