Summary
This study consists of 6 experimental cohorts, 2 of which are safety-run in cohorts.
In the Safety Run in Cohort for Sacituzumab Govitecan-hziy (SG) + pembrolizumab + carboplatin, participants will receive SG (de-escalating dose levels: 10.0mg/kg, 7.5mg/kg, or 5.0mg/kg) on Days 1 and 8 of a 21-day cycle + pembrolizumab (200mg) on Day 1 of a 21-day cycle + carboplatin area under the concentration versus time curve (AUC)5 on Day 1 of a 21-day cycle.
In the Safety Run in Cohort for SG + pembrolizumab + cisplatin, participants will receive SG (either 10mg/kg or 7.5mg/kg) on Days 1 and 8 of a 21-day cycle + pembrolizumab (200mg) on Day 1 of a 21-day cycle + cisplatin (75mg/m^2) on Day 1 of a 21-day cycle.
In the Experimental Cohort A, participants assigned to Cohort A according to tumour proportion score (TPS) status will receive SG (10mg/kg) on Days 1 and 8 of a 21-day cycle + pembrolizumab (200mg) on Day 1 of a 21-day cycle.
In the Experimental Cohort B according to TPS status, participants will receive SG (10mg/kg) on Days 1 and 8 of a 21-day cycle + pembrolizumab (200mg) on Day 1 of a 21-day cycle.
In Experimental Cohort C, participants assigned according to disease status will receive SG RP2D as determined during the safety run-in cohorts on Days 1 and 8 of a 21-day cycle + pembrolizumab (200mg) on Day 1 of a 21-day cycle + carboplatin AUC5 or cisplatin (75mg/m^2) as determined during the safety run-in cohorts on Day 1 of a 21-day cycle.
In Experimental Cohort D, participants assigned according to disease status will receive SG RP2D as determined during the safety run-in cohorts on Days 1 and 8 of a 21-day cycle + pembrolizumab (200mg) on Day 1 of a 21-day cycle + carboplatin (75mg/m^2) as determined during the safety run-in cohorts on Day 1 of a 21-day cycle. All treatments will be administered intravenously.