A Phase I/II Study of FG-M108 Plus FG-B901 in Advanced CLDN18.2-Positive Solid Tumors

Inclusion Criteria:

* Voluntarily sign the informed consent form, understand the study, are willing to comply with and have the ability to complete all trial procedures;
* Age 18-75 years (inclusive), any gender;
* Have histologically or cytologically confirmed locally advanced or metastatic solid tumors, and have failed standard therapy, or are intolerant to standard therapy, or for whom standard therapy is not available;
* CLDN18.2 positive (defined as ≥10% of tumor cells showing membrane staining ≥1+ by central laboratory IHC)
* ECOG 0-1
* Expected survival ≥3 months;
* Have at least one measurable tumor lesion according to RECIST 1.1 criteria;
* Adequate cardiac, bone marrow, liver, renal function;

Exclusion Criteria:

* Have received a live vaccine within 3 months prior to the first dose;
* Received radiotherapy within 4 weeks before the first dose
* Received Chinese herbal medicine with antitumor indications within 2 weeks before the first dose
* Previously received any therapy targeting CLDN18.2
* History of other malignancies within 3 years before the first dose
* Experienced Grade ≥3 immune-related adverse events (irAEs) from prior immunotherapy or discontinued immunotherapy due to irAEs, or have irAEs from prior immunotherapy that the investigator judges to still have clinical impact
* Toxicity from prior antitumor therapy has not recovered to NCI CTCAE v5.0 Grade 0-1
* History of severe allergic reactions, or hypersensitivity, or intolerance to any known component of the investigational products or other monoclonal antibodies
* Have brain or leptomeningeal metastases with symptoms
* Presence of clinically symptomatic body cavity effusions (pleural effusion, ascites, pericardial effusion, etc.) requiring local therapy or repeated drainage, or effusions that are poorly controlled per investigator judgment
* Uncontrolled or clinically significant cardiovascular and cerebrovascular diseases
* Clinically uncontrolled diseases such as diabetes, thyroid disorders (hormone replacement therapy does not affect enrollment), or other severe systemic diseases requiring systemic treatment
* Active or progressive infection requiring systemic treatment within 2 weeks before the first dose
* Known or suspected active autoimmune disease requiring systemic treatment
* Pregnant or breastfeeding female participants
* Known history of Hepatitis C or chronic active Hepatitis B