PeptideTreatments
Reviewed by Peptide Treatments Medical Advisory Board (Medical Advisory Board)

MK-677: Research & Evidence

Established Evidence

Published research, clinical trial data, and evidence grading for MK-677 across studied indications.

Back to MK-677 overview

Research Summary

MK-677 has over 30 human studies and 10+ RCTs demonstrating consistent GH/IGF-1 elevation. It reliably increases growth hormone levels but whether this translates to meaningful clinical outcomes remains debated. A large Phase 2 Alzheimer's trial (600+ patients) showed no cognitive benefit. Development has largely stalled with no Phase 3 trials active.

Evidence by Indication (3 indications)

Indication Tier Trials Summary
Growth hormone secretion Tier B 6 Consistently raises GH and IGF-1 levels to youthful ranges in clinical trials
Muscle wasting / sarcopenia Tier C 3 Improved lean mass in elderly subjects but mixed functional outcomes
Sleep quality Tier C 2 Increased REM and stage IV sleep duration in healthy volunteers

Graded using our evidence tier methodology.

Citations (10 sources)

  1. 1. MK-677 Phase 1: Increased GH and IGF-1. Clinical Trial

    (1995), Journal of Clinical Endocrinology & Metabolism

  2. 2. MK-677 in GH deficient adults. Clinical Trial

    (1997), Journal of Clinical Endocrinology & Metabolism

  3. 3. MK-677 in elderly: Increased GH, lean mass. Clinical Trial

    (2001), Annals of Internal Medicine

  4. 4. MK-677 in cachexia: Increased appetite and weight. Clinical Trial

    (2008), Journal of Clinical Endocrinology & Metabolism

  5. 5. Design, Biological Characterization, and Discovery of Capromorelin Derivatives as Oral Growth Hormone Secretagogue Receptor Type 1a Agonist for the Treatment of Growth Hormone Deficiency. Study

    (2025), Journal of medicinal chemistry

  6. 6. Investigating the P53-dependent anti-cancer effect of ibutamoren in human cancer cell lines. Study

    (2025), Basic & clinical pharmacology & toxicology

  7. 7. Structural basis of human ghrelin receptor signaling by ghrelin and the synthetic agonist ibutamoren. Study

    (2021), Nature communications

  8. 8. LGD-4033 and MK-677 use impacts body composition, circulating biomarkers, and skeletal muscle androgenic hormone and receptor content: A case report. Case Study

    (2022), Experimental physiology

  9. 9. Beyond the androgen receptor: the role of growth hormone secretagogues in the modern management of body composition in hypogonadal males. Study

    (2020), Translational andrology and urology

  10. 10. Reversible Gynecomastia and Hypogonadism Due to Usage of Commercial Performance-Enhancing Supplement Use. Study

    (2024), JCEM case reports