A Study of OR2805, a Monoclonal Antibody Targeting CD163, Alone and in Combination With Anticancer Agents

This Phase 1-2 study is designed to determine the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary anti-tumor activity of OR2805, a fully human IgG1 antibody that binds specifically to CD163, in subjects with advanced solid tumors. The study consists of three parts: * Part A: a dose-escalation phase to determine the maximum-tolerated dose (MTD), maximum achievable dose, or recommended phase 2 dose (RP2D) of OR2805 given alone or in combination with cemiplimab or docetaxel in a maximum of approximately 54 subjects. * Part B: an expansion phase in subjects with melanoma or non-small cell lung cancer (NSCLC) treated with OR2805 as monotherapy at the RP2D or OR2805 in combination with cemiplimab or docetaxel. Up to approximately 20 subjects will be treated in each arm of the 3 Part B cohorts to further characterize safety and determine the preliminary anti-tumor activity. * Part C: a biology cohort of up to approximately 40 subjects at the RP2D to determine the mechanism of action and potential predictors of response and pharmacodynamic markers in subjects with liposarcoma, leiomyocarcoma, or squamous cell carcinoma of the head and neck (SCCHN) or are not otherwise eligible for Part B. All subjects in Part C will undergo biopsies.