Evidence review: Open Peptide Project (verified against primary PubMed, ClinicalTrials.gov & FDA records) · Last checked 2026-10-27. ← Back to Evidence Library
Trevogrumab (REGN1033): what the evidence says
At a glance
What it is: a fully human monoclonal antibody against myostatin (GDF-8) from Regeneron. It is an antibody, not a peptide. R1
What the evidence says: Unknown the phase 2 COURAGE trial (n = 1,005) tests it with semaglutide, with or without garetosmab, for weight loss while keeping lean mass. R1 We found no peer-reviewed results. Reviews discuss the approach. R2, R3 UNVERIFIED company-reported lean-mass results.
Biggest risks: unknown in peer-reviewed data; adding garetosmab reportedly raised adverse events. UNVERIFIED (see Garetosmab).
Rating
| Human Human evidence | Limited: phase 2 registered, results unpublished R1 |
| Animal Animal / lab evidence | Not reviewed |
| Regulatory | Investigational · not FDA-approved · not on FDA's 503A or 503B bulk-substance category lists and not on FDA's compounding safety-risk page R4, R5, R6 · banned by WADA S4.3 R7 |
| Established human dose | No |
Evidence verdict: Lean-mass preservation on semaglutide: Limited (phase 2 COURAGE unpublished)
This page reports what studies used. It is not dosing advice.
Legend: HUMAN data · ANIMAL / LAB data · UNKNOWN · UNVERIFIED: not yet confirmed against a primary source
About the evidence: the only cited PubMed papers are general reviews of lean-mass loss on weight-loss drugs, not trevogrumab trial reports. R2, R3
What is it?
Related pages: garetosmab, bimagrumab, semaglutide, apitegromab.
Does it work?
- Unknown COURAGE: primary completion Jun 2026; no peer-reviewed results. R1
Is it safe?
- Unknown No published safety data.
Pipeline status (investigational)
- Sponsor: Regeneron. R1
- Trial: NCT06299098 COURAGE, primary completion Jun 2026. R1
- Expected readouts: full publication UNVERIFIED timing.
Gray-market vials: extra risks
A gray-market vial has no quality control and no guarantee of identity, strength or sterility. We test retail vials blind under the Open Peptide Standard; see /tests/. A passing test covers one batch on one date and does not mean the compound is safe.
Is it legal?
- US: not FDA-approved; no Drugs@FDA application found (openFDA searched Oct 27, 2026).
- Compounding: not on FDA's 503A or 503B bulk-substance category lists and not on FDA's compounding safety-risk page. R4, R5, R6
- Sport: WADA 2026 S4.3 (agents preventing activin receptor IIB activation) bans myostatin inhibitors at all times R7.
Study details
Study details
These are amounts researchers used, not recommendations.
| Study | People / model | Route | Amount used | Follow-up | Reported | Citation |
|---|---|---|---|---|---|---|
| No published dosing study | — | — | — | — | COURAGE results not peer-reviewed | — |
Full reference list (PubMed, CT.gov, FDA and WADA checked Oct 27, 2026)
- R1 ClinicalTrials.gov NCT06299098, COURAGE phase 2, Regeneron, active not recruiting (CT.gov API v2, checked Oct 27, 2026). https://clinicaltrials.gov/study/NCT06299098
- R2 Aimelet V, et al. Diabetes Obes Metab. 2026. PMID 41178728
- R3 Stefanakis K, et al. Metabolism. 2024. PMID 39481534
- R4 FDA, 503A bulk drug substances categories list (updated May 14, 2026). https://www.fda.gov/media/94155/download
- R5 FDA, 503B bulk drug substances categories list (updated Mar 21, 2025). https://www.fda.gov/media/94164/download
- R6 FDA, Certain bulk drug substances for use in compounding that may present significant safety risks (content current Apr 22, 2026). https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
- R7 WADA. The 2026 Prohibited List, S4.3 Agents preventing activin receptor IIB activation. https://www.wada-ama.org/sites/default/files/2025-09/2026list_en_final_clean_september_2025.pdf
Disclaimer
This page is for education and harm reduction, not medical advice or a recommendation to use Trevogrumab (REGN1033). This is an investigational drug. It is available only inside registered clinical trials; products sold online under this name are unregulated. Report problems to FDA MedWatch (https://www.fda.gov/safety/medwatch).