NCT05125016

A Trial to Find Out if REGN4336 is Safe and How Well it Works Alone and in Combination With Cemiplimab or REGN5678 for Adult Participants With Advanced Prostate Cancer

Phase 1/2 Study of REGN4336 (a PSMAxCD3 Bispecific Antibody) Administered Alone or in Combination With Cemiplimab or REGN5678 (a PSMAxCD28 Bispecific Antibody) in Patients With Metastatic Castration-Resistant Prostate Cancer

• Status: Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 370 (estimated)
• Sponsor: Regeneron Pharmaceuticals · Industry
• Sex: Male
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study is researching an investigational drug called REGN4336. Some participants may receive additional investigational drugs in combination with REGN4336. These additional drugs include REGN5678, cemiplimab and sarilumab. The main purpose of this study is to determine the safety, tolerability (how the body reacts to the drug) and effectiveness of REGN4336 alone, in combination with cemiplimab, or in combination with REGN5678. REGN4336, cemiplimab and REGN5678 are a type of treatment for cancer called immunotherapy,and are intended to activate T-cells to attack cancer cells. This study has 2 parts. The purpose of Part 1 is to determine a safe dose of REGN4336 when given alone or when given in combination with cemiplimab or REGN5678. The purpose of Part 2 is to use the REGN4336 dose(s) determined in Part 1 to further test how well REGN4336 works to shrink tumors either when given alone or in combination with cemiplimab or REGN5678. This study is looking at several other research questions, including: * What side effects may happen from taking REGN4336 alone, in combination with cemiplimab, or in combination with REGN5678? * How much REGN4336 is in the blood at different times when it is given alone, in combination with cemiplimab, or in combination with REGN5678? * Does the body make antibodies against the study drugs (REGN4336, cemiplimab, or REGN5678)?

Conditions

• Metastatic Castration-resistant Prostate Cancer

Interventions

Type	Name	Description
DRUG	REGN4336	Administered once weekly (QW) by subcutaneous (SC) injection, or intravenous (IV) infusion
DRUG	Cemiplimab	Administered concomitantly every 3 weeks (Q3W) by IV infusion
DRUG	REGN5678	Administered concomitantly QW by IV infusion
DRUG	Sarilumab	Administered once by IV infusion as prophylaxis prior to REGN4336 IV

Timeline

• Start date: 2021-11-30
• Primary completion: 2027-01-14
• Completion: 2027-01-14
• First posted: 2021-11-18
• Last updated: 2026-02-27

Locations

14 sites across 1 country: United States

Regulatory

• FDA-regulated drug study