Study of REGN4018 (Ubamatamab) Administered Alone or in Combination With Cemiplimab in Adult Patients With Recurrent Ovarian Cancer or Other Recurrent Mucin-16 Expressing (MUC16+) Cancers

Prior treatment

• Prior treatment with anti-Programmed Cell Death (PD-1)/PD-L1 therapy, as described in the protocol
• Ovarian Cancer Expansion cohorts only: More than 4 prior lines of cytotoxic chemotherapy (does not apply to low-grade serous ovarian cancer cohort)
• Prior treatment with a MUC16 - targeted therapy

Other illness

• History and/or current cardiovascular disease, as defined in the protocol
• Severe and/or uncontrolled hypertension at screening. Patients taking anti-hypertensive medication must be on a stable anti-hypertensive regimen
  • Note: Other protocol-defined Inclusion/Exclusion Criteria apply

Other

• Untreated or active primary brain tumor, central nervous system (CNS) metastases, or spinal cord compression, as described in the protocol

• Ovarian Cancer Cohorts Only: Patients with histologically or cytologically confirmed diagnosis of advanced, epithelial ovarian cancer (except carcinosarcoma), primary peritoneal, or fallopian tube cancer who have all of the following:
  • serum CA-125 level ≥2 x upper limit of normal (ULN) (in screening, not required for low-grade serous carcinoma)
  • has received at least 1 line of platinum-containing therapy or must be platinum-intolerant (applicable for dose escalation and non-randomized dose expansion cohorts)
  • documented relapse or progression on or after the most recent line of therapy
  • no standard therapy options likely to convey clinical benefit
• Adequate organ and bone marrow function as defined in the protocol
• Life expectancy of at least 3 months
• Randomized phase 2 expansion cohort (Ovarian Cancer only): Platinum-resistant ovarian cancer patients who have had 2 to 4 lines of platinum-based therapy as defined in the protocol.
• Endometrial Cancer Cohorts Only: histologically confirmed endometrial cancer that has progressed or recurrent after prior anti-Programmed Cell Death Ligand 1 (PD-1) therapy and platinum-based chemotherapy:
  • MUC16 positivity of tumor cells ≥25% by immunohistochemistry (IHC), as defined in the protocol
  • 1-4 prior lines of systemic therapy, as described in the protocol