CJC-1295 vs Ipamorelin: two receptors, one pituitary axis
Updated: October 8, 2026
Both stimulate growth hormone release from the pituitary, but through different receptors. That is why they are studied separately and in combination in pituitary signalling models.
What they are
- CJC-1295: a synthetic 29-amino-acid analogue of GHRH. The “no DAC” version (Mod GRF 1-29) lacks the albumin-binding affinity complex.
- Ipamorelin: a synthetic pentapeptide, an agonist of the GHS-R1a receptor (the ghrelin receptor).
Mechanism
CJC-1295 acts on the GHRH receptor and ipamorelin on the secretagogue receptor. In the classic literature, combining a GHRH analogue with a secretagogue produces a larger GH release than either alone.
Selectivity and half-life
- Ipamorelin was described as more selective than other secretagogues, with little effect on ACTH and cortisol in the initial studies.
- CJC-1295 without DAC has a short half-life of tens of minutes; the DAC version is much longer.
State of the evidence
Neither is an approved medicine. Human studies mostly concern the DAC variant, and those for ipamorelin are preclinical and early phase. The material on this site is for research use only.