# CJC-1295: The Long-Acting GHRH Analog, Read From the Record > CJC-1295 is a synthetic GHRH analog whose DAC variant binds serum albumin to elevate growth hormone and IGF-1 for days. A cited digest of the published research, with the DAC-versus-no-DAC distinction kept straight. A layered, plain-read digest of the published record: what the early human pharmacokinetic studies actually measured, why the DAC and no-DAC forms behave so differently, and where the human data simply stop. ## What the CJC-1295 record establishes CJC-1295 is a synthetic long-acting analog of growth-hormone-releasing hormone (GHRH), built on the hGRF(1-29) fragment with four protease-resistant amino-acid substitutions. The Drug Affinity Complex (DAC) variant adds a maleimide linker that covalently binds the peptide to circulating serum albumin, extending its plasma half-life toward that of albumin itself. In healthy adults, single subcutaneous doses of 30 or 60 µg/kg produced dose-dependent 2- to 10-fold increases in mean plasma growth hormone for six days or more, and 1.5- to 3-fold increases in IGF-1 for nine to eleven days; after multiple doses, IGF-1 stayed above baseline up to 28 days, and the estimated CJC-1295 half-life was 5.8 to 8.1 days [1]. That single-dose, multi-day signature is the whole reason CJC-1295 exists. Native GHRH is cleaved within minutes by dipeptidylpeptidase-IV (DPP-IV); the four substitutions block that cleavage, and albumin conjugation does the rest. The lead bioconjugate showed a 4-fold increase in growth-hormone area-under-the-curve over two hours versus unconjugated hGRF(1-29) in rats, with peptide detectable in plasma beyond 72 hours [2]. This site reads that record straight. Every figure on these pages maps to a published study, the long-acting DAC evidence is kept separate from the short-acting no-DAC form the forums routinely conflate with it, and the gaps — no validated human dose, no large efficacy or long-term safety trial, no regulatory approval — are marked rather than smoothed over. Start with the [CJC-1295 DAC vs no-DAC](/dac-vs-no-dac) distinction, or go straight to the [GH/IGF-1 research](/research). ## CJC-1295 as a GHRH-Analog Peptide CJC-1295 is a peptide, not a steroid and not a hormone in itself. As a CJC-1295 peptide it is a tetrasubstituted analog of hGRF(1-29) — the first 29 amino acids of human growth-hormone-releasing factor, the minimal sequence that retains full GH-releasing activity. The four substitutions (D-Ala at position 2, Gln at 8, Ala at 15, Leu at 27) stabilize the alpha-helix and block the deamidation, oxidation, and DPP-IV cleavage that clear the native molecule. The DAC peptide carries a molecular weight near 3367.9 Da before albumin conjugation; the effective circulating species after conjugation is the much larger peptide-albumin complex, around 66 kDa. The CAS registry number consistently attributed to the DAC form is 863288-34-0. These identifiers describe a research chemical: CJC-1295 is not an approved drug, and what follows on this site is a reading of its literature, not a description of a product. ## CJC-1295 in the GHRH-Analog Class As a GHRH analog, CJC-1295 binds the growth-hormone-releasing hormone receptor (GHRHR) — a class B G-protein-coupled receptor on anterior-pituitary somatotrophs. Receptor binding activates Gs/cAMP/PKA signaling, driving synthesis and pulsatile release of growth hormone, which in turn raises hepatic IGF-1 through the JAK2/STAT5 pathway [1]. The class is broader than CJC-1295. A 2025 Nature Reviews Endocrinology review synthesized the pharmacology of GHRH and its synthetic analogues — the family that also includes sermorelin and the FDA-approved tesamorelin — describing receptor signaling and the rationale for long-acting analog design [12]. CJC-1295's particular contribution to that story is duration: it was the analog engineered to make one dose last days rather than minutes. ## CJC-1295 and Ipamorelin: The Two-Receptor Rationale CJC-1295 and ipamorelin are studied as a pairing because they act through different receptors. The phrase CJC-1295 ipamorelin, common in search, refers to this combination: CJC-1295 is a GHRH analog, working on the GHRH receptor; ipamorelin is a growth-hormone-releasing peptide (GHRP), a selective secretagogue acting on the ghrelin/GHS receptor. Because GHRH analogs and GHRPs engage distinct pathways, the two release more growth hormone together than either does alone — the mechanistic basis cited for combining a GHRH analog with a GHRP. That synergy is a receptor-level rationale, not a validated regimen. CJC-1295 on its own raised growth hormone and IGF-1 in early human pharmacokinetic studies [1][3], but no controlled efficacy trial of the CJC-1295/ipamorelin combination in healthy adults exists. The pairing is described in detail on the [CJC-1295 and ipamorelin](/research) page. ### What is CJC-1295 ipamorelin? A research pairing of a GHRH analog (CJC-1295) with a selective GH secretagogue (ipamorelin); the two act through distinct receptors, the mechanistic basis cited for combining a GHRH analog with a GHRP. ## Read it by form and by evidence tier The defining property of CJC-1295 is duration, and duration depends entirely on which form you mean. The DAC variant is the long-acting species — the multi-day half-life is its whole point. The no-DAC form, [Modified GRF (1-29)](/dac-vs-no-dac), keeps the four substitutions but lacks the albumin-binding moiety and is short-acting, cleared in the minutes-to-hours range. Marketing and forums conflate them constantly; the pharmacokinetics do not. The evidence also splits by tier. Early human pharmacokinetic studies in healthy volunteers established the GH/IGF-1 kinetics [1][3]. Preclinical work in rats and GHRH-knockout mice established the bioconjugation mechanism and the once-daily growth normalization [2][4]. And a large body of claims circulating online — fixed-microgram protocols, anti-aging and muscle-building promises — sits in neither tier, because no controlled human outcome trial supports it. Those distinctions are marked throughout, including the [CJC-1295 side effects](/side-effects) page and the [FDA and WADA status](/faq). --- A layered, lit-from-behind reading of the published CJC-1295 record — the long-acting DAC evidence racked deep, the short-acting no-DAC form held in front, the human-data gaps left clear through the glass, and no clinic, vendor, or prescription anywhere behind it.