# 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 Metasta

Source: https://onco.cc/trials/nct03972657/  
OnCo record `nct03972657` (Trial). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

A phase 1/2 trial of Cemiplimab in prostate cancer and renal cell carcinoma, run by Regeneron Pharmaceuticals, now recruiting.

## Summary

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 is a phase 1/2 interventional study registered as NCT03972657 by Regeneron Pharmaceuticals, with 345 participants planned, started 2019-08-12 and due to reach its primary completion in 2027-11-15. Interventions recorded: REGN5678, Cemiplimab. Conditions listed: Metastatic Castration-Resistant Prostate Cancer (mCRPC), Clear Cell Renal Cell Carcinoma (ccRCC). No results are recorded here; the registry entry is the source.

## Fields

- Kind: Trial
- Status: recruiting
- Last checked: 2026-09-16
- Tags: ctgov-ingest
- Registry id: NCT03972657
- Phase: 1/2
- Setting: A Phase 1/2 Study of REGN5678 (Anti-PSMAxCD28) With or Without Cemiplimab (Anti-PD-1) in Patients With Metastatic Castration-Resistant Prostate Cancer and Other Tumors Associated With PSMA Expression
- Sponsor: Regeneron Pharmaceuticals
- Enrolled: 345

## Sources

- ClinicalTrials.gov NCT03972657: https://clinicaltrials.gov/study/NCT03972657

## Connected records

- cancers: [Prostate cancer](https://onco.cc/cancers/prostate/), [Renal cell carcinoma](https://onco.cc/cancers/rcc/)
- drugs: [Cemiplimab](https://onco.cc/drugs/cemiplimab/)
- companies: [Regeneron](https://onco.cc/companies/regeneron/)

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JSON: https://onco.cc/api/v1/entities/nct03972657.json