This is an open-label, Phase 1b, 3 Part (Part 1a, Part 1b, and Part 2), multi-center study.~Part 1a utilizes a 3+3 design to evaluate pembrolizumab and INCB combinations in advanced solid tumors. Group A will evaluate a JAK inhibitor with JAK1 selectivity itacitinib (INCB039110) in combination with pembrolizumab (MK-3475) and Group B will evaluate a PI3K-delta inhibitor (INCB050465) in combination with pembrolizumab to determine the maximum tolerated dose (MTD) or PAD and recommend a dose for the Part 1b safety expansion with each combination.~Once the recommended dose has been identified in Part 1a, subjects with endometrial cancer, gastric cancer, melanoma, microsatellite unstable (MSI) colorectal cancer or other MMR-deficient tumors, non-small cell lung cancer, renal cell carcinoma, head and neck squamous cell carcinoma, triple negative breast cancer, pancreatic ductal carcinoma, or transitional cell carcinoma of the genitourinary tract will be enrolled into safety expansion cohorts based upon prior treatment history with a PD-1 pathway-targeted agent (Part 1b) for each combination.~Part 2 utilizes a Simon 2-Stage design to evaluate INCB050465 in combination with pembrolizumab in patients with small cell lung cancer (SCLC) and a 1 stage design to evaluate the combination in patients with non-small cell lung cancer (NSCLC) and urothelial cancer (UC).
This is an open-label, multicenter, Phase 1b platform study in subjects with advanced or metastatic solid tumors (Part 1a) and subjects with selected solid tumors (Part 1b and Part 2). Two treatment groups (Group A and Group B) will be evaluated~Part 1a utilizes a 3+3 design to evaluate pembrolizumab and INCB combinations in advanced solid tumors. Group A will evaluate a JAK inhibitor with JAK1 selectivity itacitinib (INCB039110) in combination with pembrolizumab (MK-3475) and Group B will evaluate a PI3K-delta inhibitor (INCB050465) in combination with pembrolizumab to determine the maximum tolerated dose (MTD) or PAD and recommend a dose for the Part 1b safety expansion with each combination.~Once the recommended dose has been identified in Part 1a, subjects with select solid tumor types will be enrolled into safety expansion cohorts based upon prior treatment history with a PD-1 pathway-targeted agent (Part 1b) for each combination.~Part 2 utilizes a Simon 2-Stage design to evaluate INCB050465 in combination with pembrolizumab in patients with small cell lung cancer (SCLC) and a 1 stage design to evaluate the combination in patients with non-small cell lung cancer (NSCLC) and urothelial cancer (UC).