MK-677 (25mg) x 30 Tablets

Overview

MK-677, also known as Ibutamoren mesylate, is a potent, orally available small-molecule compound that acts as a ghrelin receptor (GHS-R1a) agonist and a selective growth hormone secretagogue. Unlike peptide-based secretagogues, MK-677 is a non-peptide spiro-aminoamide derivative, making it highly stable, bioavailable, and effective when administered orally.

In research settings, MK-677 has been studied extensively for its ability to stimulate the body’s natural growth hormone (GH) release and increase circulating levels of insulin-like growth factor-1 (IGF-1) while maintaining physiological rhythm. Its unique pharmacokinetics provide sustained activity for more than 24 hours per dose, which has positioned it as a valuable compound for exploring endocrine regulation, metabolism, body composition, and recovery processes.

Chemical Structure

1. Class: Non-peptide GH secretagogue
2. Core Scaffold: Spiro-aminoamide backbone
3. Molecular Formula: C₂₇H₃₆N₄O₅S
4. Molecular Weight: ~528.7 Da
5. PubChem IDs: 9939050 (free base) and 178024 (mesylate salt)
6. Synonyms: MK-677, MK-0677, Ibutamoren, Oratrope, L-163,191

Research Applications & Findings

1. Growth Hormone & IGF-1 Axis
   Preclinical and human studies demonstrate that MK-677 stimulates the secretion of growth hormone, resulting in elevated IGF-1 levels that remain sustained for over 24 hours, validating its long-lasting impact on the GH axis.
2. Body Composition Studies
   In models involving calorie restriction, MK-677 has been shown to improve nitrogen retention and increase lean body mass without altering cortisol production. These properties make it a strong candidate for studying nutrient partitioning and muscle maintenance under stress conditions.
3. Bone & Skeletal Research
   Investigations reveal MK-677’s ability to increase bone turnover markers and support bone mineral density, indicating its utility in studies of skeletal health and bone remodeling.
4. Sleep & Neurological Effects
   Laboratory trials have documented improvements in sleep architecture, particularly through increases in REM sleep and slow-wave sleep, providing insights into its neuromodulatory effects.
5. Metabolic and Recovery Pathways
   MK-677 is frequently employed in metabolic research to evaluate muscle recovery, adaptive responses to training, and pathways associated with energy regulation and repair.

Research Status

MK-677 remains a key compound in experimental endocrinology and metabolic studies. Its oral bioavailability, long half-life, and ability to act as a ghrelin mimetic make it a reliable tool for investigating GH-IGF-1 physiology and related metabolic outcomes.

Citations

1. PubChem Compound Summary for Ibutamoren (MK‑677 free base, CID 9939050): chemical formula C₂₇H₃₆N₄O₅S; MW 528.7 Da. Overview of MK‑677 Tablet Composition & Use
2. PubChem Compound Summary for Ibutamoren mesylate (CID 178024): mesylate salt, synonyms MK‑677, MK‑0677, Oratrope, L‑163,191. Overview of MK‑677 Tablet Composition & Use
3. Nass R, et al. “The ghrelin mimetic MK‑677 increases growth hormone and insulin-like growth factor‑I in healthy adults.” J Clin Endocrinol Metab. 2000;85(8):3202–3206. Overview of MK‑677 Tablet Composition & Use
4. Murphy MG, et al. “Oral administration of the GH secretagogue MK‑677 reverses diet-induced nitrogen wasting.” J Clin Endocrinol Metab. 1998;83(2):320–326. Overview of MK‑677 Tablet Composition & Use
5. Chapman IM, et al. “The GH secretagogue MK‑677 increases markers of bone turnover in healthy older adults.” J Bone Miner Res. 1999;14(7):1187–1194. Overview of MK‑677 Tablet Composition & Use
6. Teckman SL, et al. “Single-night dosing of MK‑677 improves REM and slow-wave sleep in humans.” Neuroendocrinology. 1997;66(4):285–292. Overview of MK‑677 Tablet Composition & Use