MK-677 (Ibutamoren)
The oral compound that reliably raises GH and IGF-1 to youthful levels, delivers measurable gains in lean mass and sleep architecture, yet consistently failed to translate those biomarker wins into functional outcomes across 30 years of clinical trials.
MK-677 (Ibutamoren) is a non-peptide, orally active growth hormone secretagogue that selectively agonises the ghrelin receptor (GHS-R1a). It increases 24-hour GH secretion by up to 97% and IGF-1 by 60-79%, producing verified gains in fat-free mass and sleep quality. However, the lean mass does not translate to strength, the bone turnover does not translate to density, and insulin resistance is a consistent pharmacological cost.
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