A Phase I, First in Human Study of CBA-1535, T Cell Engager(5T4/CD3/5T4) in Patients With Advanced Solid Tumors.

To evaluate safety and efficacy of CBA-1535 in the following two parts in a stepwise manner:

Part 1

• In Part 1, the primary objective is to evaluate the safety and tolerability of CBA-1535 in patients with solid tumors where no standard treatment is available, or who are intolerant to or non-responders to standard treatments.

Additionally, the PK, biomarker profiles, and preliminary efficacy will be evaluated. The initial dose for Part 2 will also be determined.

Part 2

• In Part 2, The primary objective is to evaluate the safety and tolerability of CBA-1535 in combination with pembrolizumab in patients with solid tumor where no standard treatment is available, or who are intolerable or non-responder to the standard treatment. Additionally, the PK, biomarker profiles, preliminary efficacy will be evaluated. The recommended Phase 2 dose (R2PD) will also be determined.

Inclusion criteria

• Patients who provide voluntary written informed consent to participate in the study
• ECOG performance status: <= 1
• Patients with 3 months or longer life expectancy
• Patients with solid tumors for whom no standard therapy is available or who are refractory to or intolerant of standard therapy

Exclusion criteria

• Patients who received other investigational drug or antibody drugs, including immune checkpoint inhibitor within 28 days prior to enrollment
• Patients who received anti-cancer drug within 14 days prior to enrollment
• Patients with previous or suspected hypersensitivity to protein preparations such as therapeutic antibodies (Chinese hamster ovary cell-derived drugs) or any component of the study drug