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NCT03972657 · ClinicalTrials.gov registry record · Phase 1

A Trial to Find Out if REGN5678 (Nezastomig) is Safe and How Well it Works Alone or in Combination With Cemiplimab for Adult Participants With Metastatic Castration-Resistant Prostate Cancer and Other Tumors

A Phase 1 study of Metastatic Castration-Resistant Prostate Cancer (mCRPC) and Clear Cell Renal Cell Carcinoma (ccRCC), sponsored by Regeneron Pharmaceuticals.

Recruiting
Registry status
Phase 1
Development phase
345
Enrollment target
20
Study locations

NCT03972657: Recruiting Phase 1 study of Metastatic Castration-Resistant Prostate Cancer (mCRPC) and Clear Cell Renal Cell Carcinoma (ccRCC), sponsored by Regeneron Pharmaceuticals.

NCT03972657 is a Phase 1 study of Metastatic Castration-Resistant Prostate Cancer (mCRPC) and Clear Cell Renal Cell Carcinoma (ccRCC) that is actively recruiting participants, run by Regeneron Pharmaceuticals. The registered enrollment target is 345 participants, below the 390-participant average among 15 other Metastatic Castration-Resistant Prostate Cancer (mCRPC) trials with a reported enrollment target (12% lower). The trial reports 20 study locations across 12 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT03972657, a Phase 1 study of Metastatic Castration-Resistant Prostate Cancer (mCRPC) and Clear Cell Renal Cell Carcinoma (ccRCC), is actively recruiting participants, sponsored by Regeneron Pharmaceuticals.

RECRUITING
Registry status
Phase 1
Development phase
345 participants
Enrollment target
20
Study locations

Study Summary

The main purpose of this study is to determine the safety, tolerability (how the body reacts to the drug\[s\]) and effectiveness (ability to treat the cancer) of REGN5678 (Nezastomig) alone, or in combination with cemiplimab. The study has 2 parts. The goal of Part 1 (dose escalation) is to determine a safe dose(s) of REGN5678 when it is given alone or in combination with cemiplimab. The goal of Part 2 (dose expansion) is to use the REGN5678 drug dose(s) found in Part 1 to see how well REGN5678 alone or in combination with cemiplimab works to shrink tumors. This study is looking at several other research questions, including: 1. Side effects that may be experienced by taking REGN5678 alone or in combination with cemiplimab 2. How REGN5678 alone or in combination with cemiplimab works in the body 3. How much REGN5678 and/or cemiplimab are present in the blood 4. To see if REGN5678 alone or in combination with cemiplimab works to reduce the size of the tumor by helping the immune system destroy the tumor

Primary Outcome

Dose Escalation Phase

Interventions

  • DRUG Cemiplimab
  • DRUG REGN5678

Study Locations (20)

New York

  • NYU Langone Health Perlmutter Cancer Center - New York
  • Icahn School of Medicine at Mount Sinai - New York
  • Columbia University - The Trustees of Columbia University in the City of New York - New York
  • Montefiore Medical Center - New York
  • University of Rochester Medical Center (URMC) - Wilmot Cancer Institute (WCI) (James P. Wilmot Cancer Center) - Rochester - Rochester

Arizona

  • Banner MD Anderson Cancer Center - Gilbert
  • Mayo Clinic - Phoenix
  • University of Arizona - Tucson

Florida

  • Mayo Clinic Jacksonville - Jacksonville
  • Moffitt Cancer Center - McKinley Drive - Tampa

Oregon

  • Providence Portland Medical Center - Portland
  • Oregon Health & Science University (3485 S. Bond) - Portland

California

  • John Wayne Cancer Institute (JWCI) - Santa Monica

Colorado

  • Sarah Cannon Research Institute (SCRI) - Denver

Connecticut

  • Yale University Hospital - New Haven

Massachusetts

  • Massachusetts General Hospital - Boston

Trial Details

FieldValue
Enrollment Target 345 participants
Start Date 2019-08-12
Est. Completion 2027-11-15
Phase Phase 1
Regeneron Pharmaceuticals

280 total trials

What NCT03972657 shows while recruiting

NCT03972657 is an interventional study that assigns participants to a tested intervention. The registered 345 participants enrollment target is mid-sized for trials with a published cap, below the 390-participant average among 15 other Metastatic Castration-Resistant Prostate Cancer (mCRPC) trials with a reported enrollment target (12% lower).

The record links to 2 conditions, with Metastatic Castration-Resistant Prostate Cancer (mCRPC) appearing as the primary indexed condition, and to 2 interventions - of which Cemiplimab is the first listed.

NCT03972657 names 20 study sites across 12 states, led by New York, Arizona, Florida.

Frequently Asked Questions

What is clinical trial NCT03972657 about?

NCT03972657 is a clinical study titled "A Trial to Find Out if REGN5678 (Nezastomig) is Safe and How Well it Works Alone or in Combination With Cemiplimab for Adult Participants With Metastatic Castration-Resistant Prostate Cancer and Other Tumors". The main purpose of this study is to determine the safety, tolerability (how the body reacts to the drug\[s\]) and effectiveness (ability to treat the cancer) of REGN5678 (Nezastomig) alone, or in combination with cemiplimab. The study has 2 parts. The goal of Part 1 (dose escalation) is to determi...

What is the current status of trial NCT03972657?

This trial is currently recruiting. It is a Phase 1 study. The enrollment target is 345 participants. The study started on 2019-08-12. Estimated completion is 2027-11-15.

What conditions does trial NCT03972657 study?

This clinical trial studies the following conditions: Metastatic Castration-Resistant Prostate Cancer (mCRPC), Clear Cell Renal Cell Carcinoma (ccRCC).

What interventions are being tested in trial NCT03972657?

The interventions under investigation include: Cemiplimab (DRUG), REGN5678 (DRUG).

Who is sponsoring clinical trial NCT03972657?

This trial is sponsored by Regeneron Pharmaceuticals, which has 280 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT03972657 being conducted?

This trial has 20 study locations across Arizona, California, Colorado, Connecticut, Florida. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for Metastatic Castration-Resistant Prostate Cancer (mCRPC)

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT03972657's enrollment target sits among peer trials

345 8th of 15 higher than 7 of 15 other Metastatic Castration-Resistant Prostate Cancer (mCRPC) trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Metastatic Castration-Resistant Prostate Cancer (mCRPC) trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT03972657, the US trial registry maintained by the National Library of Medicine. NCT03972657 (mid enrollment · wide site footprint · recruiting) retrieved and formatted by PlainTrial, see methodology.