A Study of Budigalimab (ABBV-181) in Participants With Advanced Solid Tumors

Inclusion Criteria: * Participant must have an advanced solid tumor and must not be a candidate for surgical resection or other approved therapeutic regimen known to provide clinical benefit. For dose escalation, the participant may have been previously treated with a programmed cell death 1 (PD-I) targeting agent. For dose expansion, the participant must be PD-I/PD-L1 targeting agent naïve. For Part 2 budigalimab in combination with rovalpituzumab tesirine, the participant must have SCLC with progressive disease and have failed platinum containing therapy and be PD-1/PD-L1 targeting agent naïve. For Part 3 budigalimab in combination with venetoclax, the participant must have locally advanced or metastatic NSCLC and received 1 to 4 prior lines of therapy in the advanced or metastatic setting including 1 regimen that included a PD-1 or PD-L1 targeting agent which was discontinued following disease progression. Participants who are naïve to treatment with a PD-1/PD-L1 targeting agent OR who have received more than 1 regimen containing a PD-1/PD-L1 targeting agent are NOT eligible for Part 3. * Participant has an Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 to 2 for the monotherapy cohort and an ECOG 0 to 1 for budigalimab in combination with rovalpituzumab tesirine cohort (Part 2) and budigalimab in combination with venetoclax (Part 3). * Participants have adequate bone marrow, renal, hepatic and coagulation function. * Participants must have measurable or…