Study of REGN5668 Administered in Combination With Cemiplimab or REGN4018 in Adult Women With Recurrent Ovarian Cancer

The primary objectives of the study are: In the Dose Escalation Phase: To assess the safety, tolerability, and pharmacokinetics (PK) of REGN5668 alone and in separate combinations with cemiplimab or REGN4018, in order to determine a maximally tolerated dose(s) (MTD) or recommended phase 2 dose(s) (RP2D) of these combinations In the Dose Expansion Phase: To assess the preliminary efficacy of REGN5668 in combination with cemiplimab or REGN4018, (separately by cohort and combination) as determined by the objective response rate (ORR) by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 The secondary objectives of the study are: In the Dose Escalation Phase: To assess the preliminary efficacy of REGN5668 in combination with cemiplimab or REGN4018 (separately by cohort and combination) as determined by ORR by RECIST 1.1 In the Dose Expansion Phase: To characterize the safety profile in each expansion cohort To characterize the PK of REGN5668 in combination with cemiplimab or REGN4018 (separately by cohort and combination) In both the Dose Escalation and Dose Expansion Phases: To assess preliminary efficacy of REGN5668 in combination with cemiplimab or REGN4018 (separately by cohort and combination) as measured by ORR based on immune based therapy RECIST (iRECIST), best overall response (BOR), duration of response (DOR), disease control rate (DCR), and progression-free survival (PFS) based on RECIST 1.1 and iRECIST To assess changes in CA-125 levels from baseline after treatment with REGN5668 in combinations with cemiplimab or REGN4018 (separately by cohort and combination) Immunogenicity of REGN5668, alone and in combinations with cemiplimab or REGN4018