This is a 2 part, phase 1b/2, maintenance study for patients who have achieved a partial response (PR) or complete response (CR) after completion of up to 4 cycles of a combination platinum-based chemotherapy plus CPI regimen.
Phase 1b is a 3+3 dose escalation design that will be used to determine the maximum tolerated dose (MTD) and/or the recommended phase 2 dose (RP2D) of navtemadlin in combination with pembrolizumab. A Safety Review Committee (SRC) will review the safety data during the dose escalation to decide on dose escalation and/or exploration of intermediate doses.
Phase 2 will evaluate the efficacy and safety of the RP2D of navtemadlin plus pembrolizumab compared to navtemadlin placebo plus pembrolizumab. Each Arm will have approximately 40 subjects enrolled for a total of approximately 80 subjects. Eligible subjects will be randomized 1:1. This part of the study has a randomized, controlled, double-blind design. A stratified, permuted-block randomization scheme will be used for treatment allocation.
