|Biological half-life||4–6 hours (in beagles); IGF-1 levels remain elevated in humans with a single oral dose for up to 24 hours|
159752-10-0 (mesylate salt)
|Chemical and physical data|
|Molar mass||528.662 g/mol|
|3D model (Jmol)||Interactive image|
Ibutamoren (INN) (developmental code names MK-677, MK-0677, L-163,191) is a non-peptidic, potent, long-acting, orally-active, and selective agonist of the ghrelin receptor and a growth hormone secretagogue, mimicking the growth hormone (GH)-stimulating action of the endogenous hormone ghrelin. It has been demonstrated to increase the release of, and produces sustained increases in plasma levels of several hormones including GH and insulin-like growth factor 1 (IGF-1), but without affecting cortisol levels. MK677 has shown to sustain activation of GH-IGF-1 Axis and increase in lean body mass but no change in total fat mass or visceral fat. It is currently under development as a potential treatment for reduced levels of these hormones, such as in children or elderly adults with growth hormone deficiency, and human studies have shown it to increase both muscle mass and bone mineral density, making it a promising therapy for the treatment of frailty in the elderly.
- Examorelin (hexarelin)
- GHRP-6 (SKF-110679)
- Pralmorelin (GHRP-2)
- Roy G. Smith; Michael O. Thorner (28 January 2000). Human Growth Hormone: Research and Clinical Practice. Springer Science & Business Media. pp. 45–. ISBN 978-1-59259-015-5.
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- Chapman IM, Pescovitz OH, Murphy G, Treep T, Cerchio KA, Krupa D, Gertz B, Polvino WJ, Skiles EH, Pezzoli SS, Thorner MO. Oral administration of growth hormone (GH) releasing peptide-mimetic MK-677 stimulates the GH/insulin-like growth factor-I axis in selected GH-deficient adults. Journal of Clinical Endocrinology and Metabolism. 1997 Oct;82(10):3455-63. PMID 9329386
- Murphy MG, Bach MA, Plotkin D, Bolognese J, Ng J, Krupa D, Cerchio K, Gertz BJ. Oral administration of the growth hormone secretagogue MK-677 increases markers of bone turnover in healthy and functionally impaired elderly adults. The MK-677 Study Group. Journal of Bone and Mineral Research. 1999 Jul;14(7):1182-8. PMID 10404019
- Murphy MG, Weiss S, McClung M, Schnitzer T, Cerchio K, Connor J, Krupa D, Gertz BJ; MK-677/Alendronate Study Group. Effect of alendronate and MK-677 (a growth hormone secretagogue), individually and in combination, on markers of bone turnover and bone mineral density in postmenopausal osteoporotic women. Journal of Clinical Endocrinology and Metabolism. 2001 Mar;86(3):1116–25. PMID 11238495
- Smith RG, Sun Y, Jiang H, Albarran-Zeckler R, Timchenko N. Ghrelin receptor (GHS-R1A) agonists show potential as interventive agents during aging. Annals of the New York Academy of Sciences. 2007 Nov;1119:147-64. PMID 18056963
- An Anti-frailty Pill For Seniors? New Drug Increases Muscle Mass In Arms And Legs Of Older Adults. ScienceDaily November 5th, 2008