Overview
CJC-1295 is a synthetic analog of growth hormone-releasing hormone (GHRH) designed with a Drug Affinity Complex (DAC) technology that enables covalent albumin binding after injection. This dramatically extends its plasma half-life from minutes (natural GHRH) to approximately 6–8 days, enabling less-frequent dosing in research protocols. Two variants exist in the research literature: CJC-1295 with DAC and CJC-1295 without DAC (sometimes called Modified GRF 1-29 or Mod GRF). The DAC version produces sustained GH release over days; the non-DAC version produces a more physiological pulsatile release. Both are studied for their effects on GH and IGF-1 levels in animal models.
Mechanism
CJC-1295 binds to and activates the GHRH receptor (GHRHR) on anterior pituitary somatotrophs, stimulating the synthesis and secretion of growth hormone. Its DAC modification involves a maleimide group that forms a stable amide bond with free lysine residues on serum albumin, creating an albumin-bound depot that slowly releases active peptide. This results in sustained, elevated GH and downstream IGF-1 levels throughout a research period.
Research Areas
Side Effects (Preclinical)
- – Water retention in human pharmacokinetic studies
- – Injection-site erythema and pain
- – Transient tingling or flushing (particularly non-DAC version)
- – Hypoglycemia risk with supraphysiological GH levels
Cautions
- – For research use only — not approved for human therapeutic use
- – GH axis stimulation carries theoretical risk in subjects with insulin resistance, active malignancy, or diabetic retinopathy
- – Human phase II data exists but no approved therapeutic indication
What the research shows
CJC-1295 is one of the most-studied GHRH analogs, with published human pharmacokinetic data from Phase I and II trials. The Teichman et al. (2006) study demonstrated dose-dependent increases in mean 24-hour GH concentrations of 2–10-fold and IGF-1 increases of 1.5–3-fold above baseline, sustained over multiple weeks with weekly dosing.
CJC-1295 is often researched in combination with ipamorelin, a selective ghrelin mimetic, due to their complementary mechanisms — GHRH analog + GHRP producing synergistic GH release.
References
- Long-acting growth hormone-releasing factor (CJC-1295) stimulates GH and IGF-I secretion in healthy adults — Teichman SL et al. (2006)
- Growth hormone-releasing factor analogues — Alba M et al. (2007)