A First-in-Human Trial of Safety and Efficacy of GEN1078 in Participants With Solid Tumors

The purpose of this trial is to measure the following in participants with solid cancers who receive GEN1078. * The side effects seen with GEN1078 * What the body does with GEN1078 once it is administered * What GEN1078 does to the body once it is administered * How well GEN1078 works against advanced solid tumors Trial details include: * The estimated trial duration is 8 months for an individual participant (the trial duration may vary for each participant). * The treatment duration will be an estimated 3-month treatment period (the duration of treatment may vary for each participant). * The visit frequency will be daily or visits every few days for the first few months. All participants will receive active drug; no one will be given placebo.