Analysis
Helsinn-developed selective growth-hormone secretagogue (GHRP-class) without the cortisol or prolactin elevation seen in GHRP-2 and GHRP-6. Phase 2 trial for postoperative ileus did not meet primary endpoints. The molecule is heavily marketed in research-channel protocols, often paired with CJC-1295.
Ipamorelin is a synthetic GHRP-class growth-hormone secretagogue developed by Helsinn (originally a Novo Nordisk discovery). Raun 1998 (Eur J Endocrinol) is the original characterisation paper. It defined the selective ghrelin-receptor agonism profile that differentiates ipamorelin from the older GHRP-2 and GHRP-6, both of which drove cortisol and prolactin elevations that limited clinical utility. Helsinn pursued ipamorelin for postoperative ileus through Phase 2. The key trial (Beck 2014) failed primary endpoints and the program was discontinued. Methodology v1.2 scores Ipamorelin 5.2, identical to CJC-1295. The molecule appears widely in research-channel protocols, typically paired with CJC-1295 to combine selective GH secretion (ipamorelin) with extended-half-life GHRH stimulation (CJC-1295). That dual-protocol pattern is mechanism-coherent on paper but has zero published Phase 2 efficacy data, and the research-channel material itself is among the most counterfeited compounds in the database. WADA prohibits ipamorelin under Class S2.
Top four on every dimension.
Higher is better. Numbers are tabular, the methodology is on the methodology page, and yes — vendor trust counts because counterfeit risk is real.
| # | COMPOUND | EVIDENCE | MECHANISM | HUMAN DATA | VENDOR TRUST | SAFETY | TOTAL |
|---|---|---|---|---|---|---|---|
| 6 | CJC-1295 GRF(1-29) analogue with DAC modification | 5.5 | 7.5 | 3.0 | 4.5 | 5.5 | 5.2 |
| 7 | Ipamorelin GHRP-class growth-hormone secretagogue | 5.5 | 7.0 | 3.0 | 4.5 | 6.0 | 5.2 |
| 8 | Tesamorelin synthetic GHRH analogue (Egrifta) | 8.0 | 8.0 | 7.5 | 7.5 | 7.5 | 7.7 |
| 9 | Sermorelin GHRH(1-29), formerly Geref | 5.5 | 7.0 | 5.0 | 6.0 | 6.5 | 6.0 |
Pros and cons
| WHAT WORKS | WHAT DOES NOT |
|---|---|
| Selectivity profile is genuinely cleaner than GHRP-2 and GHRP-6, selective ghrelin receptor agonism without the cortisol or prolactin spike. | The Helsinn Phase 2 program in postoperative ileus failed primary endpoints (2014); no advanced clinical development has followed. |
| Phase 1 and early-Phase 2 tolerability data is favourable across the published cohorts. | WADA-prohibited (S2); athletic-population sanctions risk. |
| Mechanism is well-characterised at the receptor level (GHSR-1a agonism). | Research-channel CJC-1295 / Ipamorelin pairing protocols have no Phase 2 efficacy evidence in any indication. |
| , | Counterfeit incidence is high; mass-spectrometry identity verification is the only reliable test. |
Alternatives we tested
Three compounds that came up in the same comparison set.
- #6 · ALSO REVIEWED5.2CJC-1295GRF(1-29) analogue with DAC modification
Long-acting GHRH analogue. Strong mechanism, defined PK profile, very limited published human evidence beyond Phase 1.
- #8 · RUNNER-UP7.7Tesamorelinsynthetic GHRH analogue (Egrifta)
FDA-approved GHRH analogue for HIV-associated lipodystrophy. The most-developed peptide in the GHRH/GHRP class with a regulated indication.
- #9 · ALSO REVIEWED6.0SermorelinGHRH(1-29), formerly Geref
29-amino-acid GHRH fragment; previously FDA-approved for paediatric GH deficiency (Geref, withdrawn 2008). Now a compounding-pharmacy product without a current FDA-approved label.
References
3 cited- Raun et al. 1998, Ipamorelin selective GH secretagogue, Eur J Endocrinol
- Beck et al. 2014, Ipamorelin postoperative ileus Phase 2, Ann Surg
- WADA Prohibited List 2026
Other reviews in this category
- #6 · ALSO REVIEWEDCJC-1295Long-acting GHRH analogue. Strong mechanism, defined PK profile, very limited published human evidence beyond Phase 1.5.2/10
- #8 · RUNNER-UPTesamorelinFDA-approved GHRH analogue for HIV-associated lipodystrophy. The most-developed peptide in the GHRH/GHRP class with a regulated indication.7.7/10
- #9 · ALSO REVIEWEDSermorelin29-amino-acid GHRH fragment; previously FDA-approved for paediatric GH deficiency (Geref, withdrawn 2008). Now a compounding-pharmacy product without a current FDA-approved label.6.0/10