A Safety Trial of GEN1042 in Japanese Subjects With Malignant Solid Tumors

This study evaluating GEN1042 will include multiple parts. In this study, GEN1042 alone (phase 1a) or GEN1042 in combination with other anticancer drug(s) (phase 1b) will be evaluated in Japanese participants. The main purpose is to assess the safety and tolerability of GEN1042 monotherapy or GEN1042 in combination in Japanese study participants with cancer.

Key Inclusion Criteria: 1. Must have measurable disease according to RECIST v1.1. 2. Eastern Cooperative Oncology Group (ECOG) performance status score of 0-1. 3. Acceptable organ and bone marrow function. 4. Participant must have a life expectancy of at least 3 months. Key Exclusion Criteria: 1. Has clinically significant toxicities from previous anticancer therapies. 2. Has rapidly progressing disease. 3. Has a history of noninfectious pneumonitis/interstitial lung disease. 4. Has a history of liver disease. 5. Has had an allogeneic tissue/solid organ transplant or autologous or allogeneic bone marrow transplant, or stem cell rescue within 3 months prior to the first dose of GEN1042. 6. Has any history of intracerebral arteriovenous malformation, cerebral aneurysm, or progressive brain metastases or stroke. 7. Has had major surgery within 4 weeks before Screening. NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.