The purpose of this first-in-human (FiH) study is to assess the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary efficacy of CKD-512 given alone and in combination with pembrolizumab in subjects with advanced or metastatic solid tumors who have failed all standard available therapy.

Inclusion Criteria:

• Histologically confirmed advanced or metastatic solid tumors.
• Progressive disease after or intolerance to standard therapy and no other effective therapeutic options available.
• Measurable disease as defined in Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1).
• Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1.
• Suitable venous access for the study-required blood sampling, including PK and PD sampling.
• Adequate clinical laboratory values and other measures

Exclusion Criteria:

• Active disease involvement of the central nervous system.
• Any serious or life-threatening medical condition unrelated to cancer, psychiatric illness, drug or alcohol abuse, that could, in the Investigator's opinion, potentially interfere with the completion of treatment according to this protocol.
• Systemic anticancer treatment within the protocol-specified period prior to the first dose.
• History of any immune-related toxicity that lead to permanent discontinuation of prior anticancer therapy
• Radiation therapy on a limited area is allowed until 4 weeks prior to the first dose of study drug, provided that the radiated lesion is clinically stable.
• Prior treatment with investigational agents ≤21 days before the first dose of study drug(s).