Zimberelimab Plus Metformin for Recurrent Ovarian Clear Cell Carcinoma

Inclusion Criteria: Age ≥ 18 years to ≤ 75 years Pathologic confirmed ovarian clear cell carcinoma Patients with recurrent or persistent ovarian clear cell carcinoma must have at least one-line pretreated platinum-containing chemotherapy According to the definition of RECIST1.1, the patient must have measurable lesions PD-L1 Combined Positive Score ≥ 1 ECOG performance status of 0 to 2 Adequate bone marrow, liver, and renal function to receive combined immunotherapy Written informed consent Exclusion Criteria: Histological evidence of non-ovarian clear cell carcinoma Lack of tumor samples (archived and/or recently obtained) Previous administration of immunotherapy Patients have been vaccinated with the live vaccine or received anti-tumor treatment within 4 weeks before the first administration An active autoimmune disease that requires systemic treatment (such as the use of disease-relieving drugs, glucocorticoids, or immunosuppressive agents) within 2 years before the first administration Synchronous or metachronous (within 5 years) malignancy other than carcinoma in situ or breast cancer (without any signs of relapse or activity) Symptomatic or uncontrolled visceral metastases that require simultaneous treatment Patients are known to be allergic to the active ingredients or excipients of zimberelimab or metformin Known human immunodeficiency virus (HIV) infection history (HIV 1/2 antibody positive). Untreated active hepatitis B (defined as HBsAg positive and the number of copies of HBV-DNA detected at the same time is greater than the upper limit of the normal value of the laboratory department of the research center) Contraindications to metformin: kidney dysfunction or abnormal creatinine from any cause; acute or metabolic acidosis