NCT04590326

A Study to Find Out How Safe REGN5668 is and How Well it Works In Adult Women When Given With Either Cemiplimab, or Cemiplimab + Fianlimab, or Ubamatamab

A Phase 1/2 Study of REGN5668 (MUC16xCD28, a Costimulatory Bispecific Antibody) Administered in Combination With Other Agents in MUC16 + Malignancies

• Status: Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 612 (estimated)
• Sponsor: Regeneron Pharmaceuticals · Industry
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study is researching an investigational drug called REGN5668 : * alone or, * combined with cemiplimab (also known as REGN2810) or, * combined with both cemiplimab and fianlimab (also known as REGN3767), or * combined with ubamatamab (also known as REGN4018), with or without sarilumab. The main purposes of this study are to: * Learn about the safety and profile of any side effects from the study drugs and to determine the highest, safe dose that can be given to participants with ovarian cancer or cancer of the uterus * Look for signs that the study drugs can treat ovarian cancer or cancer of the uterus This study has 2 parts. The purpose of Part 1 (Escalation) is to find the highest, safe dose of the study drug(s). The purpose of Part 2 (Expansion) is to use the doses chosen in Part 1. Participants with cancer of the uterus will only participate in Part 2. The study is looking at several other research questions, including: * Side effects that may be experienced by participants taking REGN5668 alone and/or in combination with cemiplimab, cemiplimab and fianlimab, or ubamatamab * How REGN5668 works in the body either alone and/or in combination with cemiplimab, cemiplimab and fianlimab, or ubamatamab * How much of the study drugs (REGN5668, cemiplimab, fianlimab, ubamatamab) are in the blood * To see if REGN5668 in combination with cemiplimab, cemiplimab and fianlimab, or ubamatamab works to treat cancer

Conditions

• Ovarian Cancer
• Fallopian Tube Cancer
• Primary Peritoneal Cancer
• Endometrial Cancer

Interventions

Type	Name	Description
DRUG	REGN5668	Administer per the protocol
DRUG	Cemiplimab	Administer per the protocol
DRUG	Ubamatamab	Administer per the protocol
DRUG	Sarilumab	Administer per the protocol
DRUG	Cemiplimab + Fianlimab [Fixed Dose Combination (FDC)]	Administer per the protocol

Timeline

• Start date: 2020-12-08
• Primary completion: 2027-03-25
• Completion: 2027-11-30
• First posted: 2020-10-19
• Last updated: 2025-11-21

Locations

24 sites across 4 countries: United States, Belgium, France, Spain

Regulatory

• FDA-regulated drug study