Tabimorelin

also known as: NN703, NNC 26-0703

Novo Nordisk's discontinued oral GH secretagogue — evaluated in Phase 2 for adult GH deficiency in the late 1990s and early 2000s; discontinued for commercial/strategic reasons. Relevant today as a historical archetype alongside MK-677 and capromorelin.

An early small-molecule orally active ghrelin receptor (GHS-R1a) agonist developed by Novo Nordisk in the late 1990s and early 2000s as an oral GH secretagogue candidate for adult GH deficiency and elderly somatopause indications. Produced dose-dependent increases in GH and IGF-1 in Phase 2 but was discontinued for commercial/strategic reasons before advancing to Phase 3. Included for reference as a historical archetype of the oral-ghrelin-agonist class alongside MK-677 (ibutamoren), capromorelin, and anamorelin.

Mechanism of action

Agonism at the ghrelin receptor (GHS-R1a) in hypothalamus and pituitary, producing pulsatile GH release through the same pathway as MK-677 and the peptidic GHRPs. As with other GHS agonists, chronic administration produces moderate increases in IGF-1.

Primary uses

Historical: adult growth hormone deficiency (investigational)
Historical: elderly somatopause (investigational)

Typical dosing

Not established

Not available for any current use.

Regulatory status

Not approved. Novo Nordisk discontinued development in the early 2000s. No current active program.

References

[pubmed] Svensson J, et al. "Two-month treatment of obese subjects with the oral growth hormone (GH) secretagogue MK-677 increases GH secretion, fat-free mass, and energy expenditure." J Clin Endocrinol Metab, 1998;83:362-369 (citing tabimorelin among early orally active GHS candidates).
[manufacturer] Novo Nordisk NN703 clinical program; development discontinued. Referenced in industry pharmacology reviews of oral GH secretagogues.

Related peptides

MK-677

An orally active non-peptide ghrelin receptor agonist — included here by convention because it is universally marketed alongside peptide GH secretagogues. FDA warns of heart failure risk.

Anamorelin

Ono Pharmaceutical's oral ghrelin receptor agonist (Adlumiz) — approved in Japan in 2021 for cancer cachexia in non-small-cell lung, gastric, pancreatic, and colorectal cancers; FDA issued a Complete Response Letter in 2020 and anamorelin remains unapproved in the US.

Capromorelin

⚠ Veterinary use only — not approved for humans. Elanco's oral ghrelin agonist (Entyce for dogs 2016, Elura for cats 2020) — FDA-approved only for veterinary appetite stimulation. Included for completeness because it is a genuine approved ghrelin receptor agonist with significant online search volume.

Macimorelin

An orally active ghrelin receptor agonist FDA-approved in 2017 as a diagnostic test for adult growth hormone deficiency — the only oral alternative to the insulin tolerance test.

Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.