A Phase 1 Study of ZL-1218 in Subjects With Advanced Solid Tumors

Inclusion Criteria: * Adult men and women ≥ 18 years of age. If 18 years is not the age of majority, then adult men and women ≥ age of majority per local regulation. * Eastern Cooperative Oncology Group (ECOG) performance status of 0-1. * Life expectancy \> 12 weeks. * Subjects must have histologically confirmed and documented diagnosis of locally advanced unresectable or metastatic advanced solid tumor that is refractory to standard treatment, or intolerant to standard treatment, or for which no standard treatment exists.Subjects must have at least one target lesion as defined by RECIST v1.1 on CT, PET/CT, or MRI scan. * Subjects must have a site of disease which is not previously irradiated and is safe and amenable to biopsy per the treating institution's guidelines. Subjects must be willing to undergo a tumor biopsy at screening and on treatment, per the protocol guidelines. * Subjects must have a site of disease which is not previously irradiated and is safe and amenable to biopsy per the treating institution's guidelines. Subjects must be willing to undergo a tumor biopsy at screening and on treatment, per the protocol guidelines. Exclusion Criteria: * Symptomatic or uncontrolled brain metastasis requiring concurrent treatment, inclusive of but not limited to surgery, radiation, and/or corticosteroids. * Prior exposure to CCR8 inhibitor (anti-CCR8 antibody) or hypersensitivity to any ingredient of the study drug. * Out of range value within 10 days prior to the first dose of study treatment. * Subjects have received a live or live-attenuated vaccine within 30 days of planned start of study therapy. * Subjects with known history of, or any evidence of active, non-infectious pneumonitis. * Impaired cardiac function or clinically significant cardiac disease within the last 3 months before administration of the first dose of the study drug. * Treatment with any systemic anti-cancer treatment (including investigational products) within 4 weeks before first dose of study drug. * Non-palliative radiotherapy within 2 weeks prior to first dose of study drug or have had history of radiation pneumonitis. * Major surgery within 4 weeks of the first dose of study drug. * Infections requiring systemic antibiotic therapy. * Any medical conditions that would, in the investigator's judgement, prevent the subject's participation in the clinical study due to safety concerns, compliance with the study procedures, or interpretation of the study results.