Ipamorelin
Also searched as: NNC 26-0161
Ipamorelin is a synthetic pentapeptide that binds the ghrelin receptor and stimulates the pituitary to release growth hormone. It is described as selective because, in the studies conducted, it produced comparatively little effect on cortisol and prolactin relative to earlier secretagogues. It was investigated pharmaceutically and discontinued.
What the research has looked at
- Growth hormone release in animal and early human studies
- Post-operative ileus, in a clinical programme later discontinued
- Selectivity relative to cortisol and prolactin release
This is a description of what has been studied, not a claim about what it does. Evidence level: early human data.
Legal position in the UK
Not a licensed medicine in the UKNot licensed as a medicine in the UK. Prohibited in sport at all times under WADA class S2 as a growth hormone secretagogue.
Handling and storage
Lyophilised powder. Often supplied in smaller vial sizes than repair peptides, which means the mixing arithmetic matters more: a small vial in too much water produces a dose that lands between clicks.
Vial sizes: Commonly 2mg or 5mg per vial. Where a manufacturer supplies handling instructions, those take precedence over anything general.
Questions
- Why was Ipamorelin never approved?
- Its clinical programme, aimed at post-operative ileus, was discontinued. Discontinuation is usually about trial results or commercial priorities rather than a specific safety finding, but the practical outcome is the same: it did not complete approval.
- What does 'selective' mean here?
- That in the studies conducted it raised growth hormone with relatively little effect on cortisol and prolactin, compared with older secretagogues that affected several hormones at once.