What it is
Ipamorelin is a synthetic pentapeptide, Aib-His-D-2-Nal-D-Phe-Lys-NH2, developed at Novo Nordisk from the growth hormone releasing peptide series. It acts at the ghrelin receptor and was described as the first growth hormone secretagogue selective for growth hormone release. It has been researched in endocrinology and, later, in gastrointestinal motility.
How it works
It is an agonist at the growth hormone secretagogue receptor GHS-R1a on pituitary cells and on enteric neurons. Pharmacological profiling with GHRP and GHRH antagonists showed it releases growth hormone through the GHRP-like receptor rather than the GHRH receptor.
Regulatory status
- Cosmetic ingredient
- Research compound
- In clinical trials
- Approved medicine
Not approved as a medicine by the FDA or the EMA. Some are registered in individual countries. Supplied for laboratory research only.
What published research is studying
- Selectivity of growth hormone release relative to ACTH, cortisol, prolactin, LH, FSH and TSH
- Pharmacokinetics and the shape of the growth hormone response in healthy volunteers
- Recovery of gut motility after bowel resection (phase 2 postoperative ileus trial)
- Longitudinal bone growth and bone mineral content in rodent models
Key findings
In conscious swine, ipamorelin released growth hormone with potency similar to GHRP-6. It did not raise ACTH or cortisol above the levels seen after GHRH, even far above its ED50.
Raun K et al., Eur J Endocrinol 1998In healthy male volunteers studied at five escalating 15-minute infusion rates, kinetics were dose-proportional and the terminal half-life was about 2 hours. Growth hormone peaked once, at roughly 0.67 hours.
Gobburu JV et al., Pharm Res 1999In a double-blind phase 2 trial in 114 adults after bowel resection, median time to a first tolerated solid meal was 25.3 hours versus 32.6 hours on placebo. The difference was not statistically significant (p = 0.15).
Beck DE, Sweeney WB, McCarter MD, Int J Colorectal Dis 2014In adult female rats dosed for 15 days, longitudinal tibial growth rate rose dose-dependently from 42 to 52 micrometres per day. Total IGF-I and bone turnover markers were unchanged.
Johansen PB et al., Growth Horm IGF Res 1999
What the studies measured
Study durations
- Phase 2 postoperative ileus trial: dosing from postoperative day 1 to day 7 or hospital discharge (NCT00672074).
- Rat longitudinal bone growth study: 15 days of dosing with tetracycline labelling on days 0, 6 and 13 (Johansen 1999).
- Rat bone mineral content study: 12 weeks of continuous subcutaneous infusion in 13-week-old females (Svensson 2000).
Endpoints
- Peak plasma growth hormone, ED50 and Emax
- Plasma ACTH, cortisol, prolactin, LH, FSH and TSH as selectivity measures
- Terminal half-life, clearance and volume of distribution
- Time from first dose to tolerance of a standardised solid meal
- Longitudinal bone growth rate and bone mineral content by DXA
How strong is the evidence?
Human data amount to one pharmacokinetic study in healthy volunteers and one phase 2 trial that missed its efficacy endpoint. The rest is animal work.
Common questions
Is Ipamorelin an approved medicine?
Research compound. Not approved as a medicine by the FDA or the EMA. Some are registered in individual countries. Supplied for laboratory research only.
How much human research is there on Ipamorelin?
Human data amount to one pharmacokinetic study in healthy volunteers and one phase 2 trial that missed its efficacy endpoint. The rest is animal work.
Does UU supply Ipamorelin?
Yes, as premium-grade research material for laboratory use. Every batch is tested by an independent lab and the certificate of analysis is published.