Source comparison
MK-677 and Ibutamoren: Practical Comparison
Chemical Structure C₂₇H₃₆N₄O₅S (peptidomimetic GH secretagogue) C₂₇H₃₆N₄O₅S (identical molecule) No structural difference. MK-677 is the research code, ibutamoren is the INN. Both refer to the same compound. Receptor Target GHSR-1a (ghrelin receptor) in hypoth
This comparison does not assign a generated winner or score.
- Chemical Structure
- C₂₇H₃₆N₄O₅S (peptidomimetic GH secretagogue)
- C₂₇H₃₆N₄O₅S (identical molecule)
- No structural difference. MK-677 is the research code, ibutamoren is the INN. Both refer to the same compound.
- Receptor Target
- GHSR-1a (ghrelin receptor) in hypothalamus
- Same mechanism. Selective agonism at the growth hormone secretagogue receptor triggers endogenous GH pulses without external peptide.
- Half-Life
- 4–6 hours (oral administration)
- Identical pharmacokinetics. Single daily dosing maintains stable receptor activation across a 24-hour cycle.
- Bioavailability
- ~60% oral bioavailability (survives first-pass metabolism)
- Same absorption profile. Peptidomimetic structure allows oral dosing, unlike GHRP peptides requiring injection.
- IGF-1 Elevation
- 60–90% increase at 25mg daily (observed in Phase 2 trials)
- Same efficacy. Both names describe the compound that elevates circulating IGF-1 via pituitary GH stimulation.
- Regulatory Status
- Research-grade only (not FDA-approved for human therapeutic use)
- Both names carry the same regulatory classification. Available through licensed research suppliers like Real Peptides for investigational purposes only.