Study of CHS-388 (Formerly Known as SRF388) in Patients With Advanced Solid Tumors

This is a Phase 1/1b, open-label, first-in-human (FIH), dose-escalation and expansion study of CHS-388, a monoclonal antibody targeting IL-27, as a monotherapy and in combination in patients with solid tumors that will be conducted in 4 parts: * Part A: CHS-388 monotherapy dose-escalation portion of the study will evaluate the safety, tolerability, PK, pharmacodynamics, and preliminary efficacy of CHS-388 as monotherapy in patients with advanced solid tumors. * Part B: CHS-388 monotherapy expansion cohorts will evaluate the safety, efficacy, tolerability, PK, and pharmacodynamics of CHS-388 monotherapy in patients with advanced or metastatic ccRCC, advanced or metastatic HCC, and advanced or metastatic NSCLC in indication specific cohorts. * Part C will evaluate the safety, preliminary efficacy, tolerability, and PK of CHS-388 in combination with pembrolizumab in patients with advanced RCC,HCC, or NSCLC. * Part D will evaluate the safety, preliminary efficacy, tolerability, and PK of CHS-388 in combination with toripalimab in patients with advanced NSCLC.