First in Human Study of M6223

Participants will receive an intravenous (IV) infusion of M6223 at escalated doses every 2 weeks (Q2W) or every 3 weeks (Q3W) on Day 1 of each Cycle (Each cycle is of 14 days) according to the recommendation of the SMC(Safety Monitoring Committee) until the maximum tolerated dose(MTD) has been reached or confirmed disease progression.

Participants will receive an IV infusion of bintrafusp alfa Q2W on Day 1 of each Cycle (Cycle is 14 days) until confirmed disease progression.

Participants will receive an IV infusion of M6223 at escalated doses Q2W on Day 1 of each Cycle (Each cycle is of 21 days) according to the recommendation of the SMC until the MTD has been reached or confirmed disease progression.