INCMGA00012 in Combination With Chemoradiation in Participants With Stage III Non-Small Cell Lung Cancer (POD1UM-301)

INCMGA00012 administered intravenously every 3 weeks on Day 1 of each 21-day cycle for 4 cycles, followed by a consolidation part of INCMGA00012 administered intravenously on Day 1 of each 28-day cycle for up to12 cycles.

Placebo administered intravenously every 3 weeks on Day 1 of each 21-day cycle for 4 cycles, followed by a consolidation part of placebo administered intravenously on Day 1 of each 28-day cycle for up to 12 cycles.

Pemetrexed administered intravenously every 3 weeks on Day 1 of each cycle with either carboplatin or cisplatin (nonsquamous NSCLC only) for 2 cycles (if radiation therapy is started on Cycle 1 Day 1) or 3 cycles (if radiation therapy is started after Cycle 1).

Cisplatin administered intravenously every 3 weeks on Day 1 of each cycle with either etoposide or pemetrexed (nonsquamous NSCLC only) for 2 cycles (if radiation therapy is started on Cycle 1 Day 1) or 3 cycles (if radiation therapy is started after Cycle 1).

Carboplatin administered intravenously every 3 weeks on Day 1 of each cycle with either pemetrexed (nonsquamous NSCLC only) or paclitaxel for 2 cycles (if radiation therapy is started on Cycle 1 Day 1) or 3 cycles (if radiation therapy is started after Cycle 1).

Paclitaxel administered intravenously every 3 weeks on Days 1, 8, and 15 of each cycle with carboplatin for 2 cycles (if radiation therapy is started on Cycle 1 Day 1) or 3 cycles (if radiation therapy is started after Cycle 1).

Etoposide administered intravenously every 3 weeks on Days 1-3 of each cycle with cisplatin for 2 cycles (if radiation therapy is started on Cycle 1 Day 1) or 3 cycles (if radiation therapy is started after Cycle 1).

Total dose of 60 Gy ± 10% (54 to 66 Gy) in 2 Gy daily fractions.