INCMGA00012 Plus Chemotherapy in Participants With Advanced Solid Tumors (POD1UM-105)

Inclusion Criteria: * Advanced and/or metastatic solid tumors including the following: histologically or cytologically confirmed diagnosis of Stage IIIB not amenable to curative treatment or Stage IV non-small cell lung cancer (pemetrexed-platinum treatment groups must have nonsquamous histology type); and histologically or cytologically confirmed diagnosis of advanced/metastatic unresectable malignant pleural mesothelioma. * No prior systemic treatment with the following exceptions: participants with a known sensitizing mutation (eg, BRAF, EGFR, ALK, or ROS1) should have had disease progression on or following an approved targeted tyrosine kinase inhibitor; and participants who received adjuvant or neoadjuvant chemotherapy are eligible if the adjuvant/neoadjuvant therapy was completed at least 6 months before the date of enrollment. * Measurable or nonmeasurable tumor lesions per RECIST v1.1. * Eastern Cooperative Oncology Group performance status 0 to 1. Exclusion Criteria: * Received prior treatment with checkpoint inhibitor agents (such as anti-PD-1, anti-PD-L1, anti-PD-L2, or anti-CTLA-4). * Had major surgery within 3 weeks before the first dose of study treatment. * Received radiation therapy to the lung(s) that is \> 30 Gy within 6 months of the first dose of study treatment. * Received palliative radiotherapy within 7 days before the first dose of study treatment. * Has ≥ Grade 2 residual toxicities from the most recent prior therapy (except alopecia). * Organ func…