This study is enrolling participants with advanced solid tumors. The purpose of the study is to see how safe the study drug UCB6114 is and how the body processes the drug when given alone or in combination with selected standard of care (SOC) regimens. Participants will receive UCB6114 via intravenous (IV; injected into a vein) infusion (drip) every 2 weeks, on Days 1 and Day 15 of each treatment cycle. If they continue to additional cycles, the infusions will continue to take place every 2 weeks according to the same schedule. Participants will be in this trial for a planned period of at least 2 cycles of study treatment (around 8 weeks) but should the Study Doctor decide that he/she is benefiting from treatment, he/she can remain in the study for additional cycles of treatment until he/she decide to withdraw from the study, he/she experiences any unacceptable side effects due to the treatment or if the disease worsens.