Growth hormone axis

CJC-1295 (With & Without DAC)

Reviewed 22 October 2026 · How we research

Also known as: CJC 1295, CJC-1295 DAC, Mod GRF 1-29, CJC no DAC

What is CJC-1295?

CJC-1295 is a lab-made version of the first 29 amino acids of growth-hormone-releasing hormone (GHRH), with four substitutions that make it resist breakdown. It comes in two very different forms, and confusing them is the most common mistake people make:

• CJC-1295 with DAC — carries a “Drug Affinity Complex” that binds albumin in the blood, stretching its half-life to around a week.
• CJC-1295 without DAC (also sold as Mod GRF 1-29) — lasts around 30 minutes and produces a short growth-hormone pulse.

The no-DAC form is the one usually paired with ipamorelin in “CJC/Ipa” blends.

How CJC-1295 works

Both forms bind GHRH receptors on the pituitary and increase growth hormone release, which raises IGF-1 from the liver. The short no-DAC form mimics a natural GHRH pulse; the DAC form produces sustained elevation of baseline growth hormone. Combining a GHRH analogue with a ghrelin mimetic like ipamorelin produces a larger GH release than either alone, because the two act on different receptors.

What the research shows

• In healthy adults a single injection of CJC-1295 with DAC raised mean growth hormone 2–10-fold for six days or more, and IGF-1 1.5–3-fold for 9–11 days.
• Growth hormone stayed pulsatile even with continuous stimulation from the DAC form.
• Clinical development stopped in 2006 after a death in a phase 2 trial in HIV lipodystrophy; the company stated it was unrelated, but the programme did not resume.

Compare: CJC-1295 vs Ipamorelin

CJC-1295 side effects

In the human DAC studies the most common effects were injection-site reactions, flushing, headache and transient water retention. Raised growth hormone and IGF-1 can affect blood glucose. Long-term safety has never been studied.

UK legal status

CJC-1295 is not licensed in any country and has no UK medical use. It is sold only as a research peptide and is prohibited in sport by WADA (growth-hormone-releasing factors, S2).

More detail, including current UK research-vial prices: CJC-1295 UK guide. For the doses used in published studies and the reconstitution maths: CJC-1295 dosing in the literature.

References

1. Teichman SL, et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91:799–805.
2. Ionescu M, Frohman LA. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. J Clin Endocrinol Metab. 2006;91:4792–4797.