What is the difference between CJC-1295 with and without DAC?

CJC-1295 with DAC has the albumin-binding modification and a half-life of 6–8 days. "CJC-1295 without DAC" (also called Modified GRF 1-29) lacks this modification and behaves more like sermorelin — a short-acting GHRH analog. They are commonly confused, but are pharmacologically distinct compounds.

Is the ipamorelin + CJC-1295 combination studied in humans?

No. The combination is popular in biohacking protocols, but as of this writing there are no published human clinical trials testing the combination for any outcome. The pharmacological rationale is based on the complementary mechanisms of GHRH-receptor and GHSR stimulation shown in animal research.

How long does CJC-1295 keep GH elevated?

The Teichman 2006 human PK study showed GH and IGF-1 elevations for 6 to 9 days depending on dose. This extended activity is the defining feature of the compound and the rationale for once- or twice-weekly dosing protocols.

Human (observational)Research compound

CJC-1295

Also known as: CJC-1295 with DAC, Drug Affinity Complex-GHRH, DAC:GRF

A long-acting GHRH analog engineered for albumin conjugation — the first GH-secretagogue peptide demonstrated to sustain elevated GH and IGF-1 for over a week in a human pharmacokinetics study.

InjectableCAS 863288-34-0

Last updated June 21, 2026

The long-acting GHRH analog: one injection keeps GH and IGF-1 elevated for the better part of a week, and that much is shown in humans. What is not shown is whether it does anything you would actually want — there is a single human PK study and zero trials measuring body composition, strength, or long-term safety.

Mechanism

CJC-1295 starts from GHRH(1-29) — the same sequence behind sermorelin — then bolts on Drug Affinity Complex (DAC) technology that covalently latches the peptide onto circulating albumin. That albumin tether is the whole trick: where sermorelin clears in minutes, CJC-1295 with DAC keeps stimulating GH for six to eight days off a single injection. It activates pituitary GHRH receptors and drives pulsatile GH the physiological way. In practice that means dosing once or twice a week instead of daily — the feature that made it a biohacking favorite. One source of confusion worth flagging: a version without the DAC modification (CJC-1295 without DAC, also called "Modified GRF 1-29") is short-acting, much closer to sermorelin.

What the research shows

Strip away the forum talk and the human evidence for CJC-1295 comes down to one study. Teichman et al. (2006, JCEM) gave it to healthy adults and tracked the pharmacokinetics: a single subcutaneous dose produced dose-dependent rises in GH and IGF-1 lasting up to nine days. A real result — but a PK/PD study, not a randomized trial with clinical endpoints like body composition, strength, or safety over time. No published RCT has tested CJC-1295 against any therapeutic outcome in humans. The compound was first identified in rats by Jetté et al. (2005, Endocrinology). Everything past 'it reliably raises GH for about a week' is, at this point, unmeasured.

Evidence grade: Human (observational) — Human data from non-randomized studies: cohorts, case series, case reports.

Benefits studied

GH and IGF-1 stay elevated up to 9 days after a single dose in healthy adults (Teichman PK/PD study)
Dose-dependent GH secretion in healthy adults, with no immediate adverse events in that study
Confirmed activation of pituitary GHRH receptors in rats (the foundational mechanistic work)

Risks & unknowns

No RCTs with clinical endpoints — efficacy for body composition or any therapeutic use is unproven in humans
Long-acting GH stimulation means prolonged exposure if adverse effects occur
Fluid retention, joint pain, and other GH-related side effects possible
Sold exclusively as an unregulated research compound — quality is supplier-dependent
Long-term effects of chronically elevated IGF-1 (beyond the study window) are unknown
Banned in sport by WADA

Regulatory status

Research compound. Sold "for research use only" — not approved for human consumption.

Goals studied: GH / IGF-1 support, Body composition

FAQ

What is the difference between CJC-1295 with and without DAC?: CJC-1295 with DAC has the albumin-binding modification and a half-life of 6–8 days. "CJC-1295 without DAC" (also called Modified GRF 1-29) lacks this modification and behaves more like sermorelin — a short-acting GHRH analog. They are commonly confused, but are pharmacologically distinct compounds.
Is the ipamorelin + CJC-1295 combination studied in humans?: No. The combination is popular in biohacking protocols, but as of this writing there are no published human clinical trials testing the combination for any outcome. The pharmacological rationale is based on the complementary mechanisms of GHRH-receptor and GHSR stimulation shown in animal research.
How long does CJC-1295 keep GH elevated?: The Teichman 2006 human PK study showed GH and IGF-1 elevations for 6 to 9 days depending on dose. This extended activity is the defining feature of the compound and the rationale for once- or twice-weekly dosing protocols.

Sources

[1]
Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analog
Jetté L, Léger R, Thibaudeau K, Benquet C, Robitaille M, Pellerin I, Paradis V, van Wyk P, Pham K, Bridon DP · Endocrinology · 2005 · PMID 15817669 · model: animal
Identification and characterization of CJC-1295 in rats, demonstrating that albumin conjugation of GHRH(1-29) produces a long-acting GRF receptor agonist with sustained GH-stimulating activity.
[2]
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
Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA · The Journal of Clinical Endocrinology and Metabolism · 2006 · PMID 16352683 · model: human
Pharmacokinetic/pharmacodynamic study in healthy adults showing that a single CJC-1295 injection produced dose-dependent, sustained increases in GH and IGF-1 for up to nine days — the only published human data on this compound.