MK-677 vs Sermorelin
Research & educational use only. This content is not medical advice. Consult a qualified healthcare professional before using any peptide compound.
MK-677 and Sermorelin are both growth hormone peptides that come up together constantly. This is a side-by-side comparison on the data that actually matters — evidence tier, FDA status, human trials, and how to source each safely — not hype. It is for research and educational purposes only.
MK-677 vs Sermorelin: side-by-side
| MK-677 | Sermorelin | |
|---|---|---|
| Evidence tier | Tier 2 | Tier 2 |
| FDA status | Investigational | Not FDA Approved |
| Human RCTs | 5 | 2 |
| Subjects enrolled | 600 | 150 |
| Animal studies | 20 | 20 |
| Category | growth hormone | growth hormone |
| Half-life | Long half-life supporting once-daily oral dosing. | Short plasma half-life (minutes). |
| Community logs | 1 | 0 |
Key differences
Both MK-677 and Sermorelin sit at the same evidence tier (Tier 2), so neither has a clear edge in how strong its human data is. Neither is FDA approved for human use — both are investigational / not fda approved and treated as research compounds in the US.
MK-677 has 5 human trials on record (600 subjects) versus Sermorelin's 2 (150 subjects). Evidence tiers are a shorthand for how strong that human data is — see our guide to understanding peptide evidence tiers for how to weigh them.
What is MK-677?
MK-677 (ibutamoren) is an orally active, non-peptide growth hormone secretagogue that mimics ghrelin at the GHS-R1a receptor to raise growth hormone and IGF-1. Despite extensive clinical investigation it has never received FDA approval, and recognized effects include increased appetite and reduced insulin sensitivity.… Full MK-677 breakdown →
What is Sermorelin?
Sermorelin is a synthetic peptide corresponding to the first 29 amino acids of growth hormone-releasing hormone (GHRH 1-29). It was previously marketed in the United States (as Geref) for diagnostic and pediatric growth indications and is no longer sold as an approved product, though it remains available through… Full Sermorelin breakdown →
Where to buy MK-677 or Sermorelin safely
Both are sold by research-chemical suppliers, not pharmacies, so the source matters as much as the compound. Before buying either, vet sellers on third-party lab testing and enforcement history in the ranked directory of trusted peptide sellers — or jump straight to vetted sources for MK-677 or Sermorelin. PeptidesHub does not sell either compound.
Frequently asked questions
MK-677 and Sermorelin are both growth hormone peptides. Both MK-677 and Sermorelin sit at the same evidence tier (Tier 2), so neither has a clear edge in how strong its human data is. Neither is FDA approved for human use — both are investigational / not fda approved and treated as research compounds in the US. See each compound's full evidence breakdown for the underlying studies.