CJC-1295 is a long-acting GHRH analog studied in two pharmacokinetically opposite forms

What the CJC-1295 literature establishes

CJC-1295 is a synthetic analog of growth-hormone-releasing hormone (GHRH). It binds the GHRH receptor on anterior-pituitary somatotrophs and stimulates pulsatile growth-hormone (GH) release, which raises hepatic insulin-like growth factor 1 (IGF-1) ^[1]. Four amino-acid substitutions on the first 29 residues of human GH-releasing factor block the proteases that clear native GHRH; in the DAC variant a covalent bond to serum albumin extends the plasma half-life toward that of albumin itself ^[2].

The headline finding is duration. In healthy adults, single subcutaneous doses of 30 or 60 µg/kg produced dose-dependent 2- to 10-fold increases in mean plasma GH for six days or more and 1.5- to 3-fold increases in IGF-1 for 9 to 11 days; after multiple doses IGF-1 stayed above baseline up to 28 days, and the estimated half-life of CJC-1295 was 5.8 to 8.1 days ^[1]. That is the multi-day arc that defines the DAC form.

The second finding is restraint of mechanism. Continuous stimulation by a long-acting GHRH analog might have been expected to flatten GH into a steady leak. It did not. In healthy men, a single 60 or 90 µg/kg dose raised basal GH roughly 7.5-fold, mean GH about 46%, and IGF-1 about 45% one week later, while the frequency and amplitude of pulsatile GH secretion were unchanged ^[3]. The pituitary kept its pulse.

What the literature does not establish matters as much. The human record is limited to early pharmacokinetic studies in healthy volunteers; no controlled trial reports body-composition, performance, or long-term safety outcomes ^{[1] [3]}. CJC-1295 is not approved for human use anywhere, and the original long-acting DAC development program was discontinued. This site inscribes that record straight — the GH and IGF-1 findings, the doses used in the research literature, and the reported and theoretical concerns — and marks where it ends. The full reference list carries every source.

CJC-1295 peptide: the research-chemical profile

CJC-1295 is a research peptide, not an approved medicine and not an anabolic steroid. It is a 29-residue peptide (molecular weight approximately 3367.9 Da for the DAC species before albumin conjugation; CAS 863288-34-0) that acts on the body's own GH axis rather than supplying a hormone directly ^{[1] [2]}. As a peptide it has negligible oral bioavailability; every characterized study used the subcutaneous route ^[1].

Handled as a research chemical, CJC-1295 ships lyophilized and is reconstituted with bacteriostatic water and refrigerated. That is laboratory handling context, not a use instruction — the compound has no approved human indication. The peer-reviewed evidence base in healthy adults is thin and short-term, and most dosing protocols circulating online are not derived from controlled human trials. The record below is the published science, organized so a careful reader can see exactly what was measured and on whom.

CJC-1295 ipamorelin: why the two are studied together

CJC-1295 and ipamorelin are paired because they pull the same lever from two directions. GHRH analogs and growth-hormone-releasing peptides (GHRPs) act through distinct receptors, and their GH release is supra-additive: co-administration produces more GH than the sum of either alone ^[7]. Ghrelin and GH secretagogues likewise potentiate GHRH-induced GH release, reinforcing the two-pathway model ^[8].

Ipamorelin is the partner of choice in this GHRH + GHRP synergy because it was characterized as the first highly selective GH secretagogue — it releases GH with minimal effect on ACTH, cortisol, or prolactin ^[9]. CJC-1295 supplies the long-acting GHRH-receptor arm; ipamorelin supplies the selective secretagogue arm. The combination is a research pairing, not a tested therapy: no controlled trial has measured the CJC-1295/ipamorelin pairing for body-composition outcomes.

The two forms, side by side

The single most consequential fact about CJC-1295 is that the name covers two pharmacokinetically opposite forms, and marketing routinely conflates them. The CJC-1295 DAC vs no-DAC distinction is the core due-diligence question.

The DAC variant carries a C-terminal lysine functionalized with a maleimidopropionyl linker that covalently bonds circulating serum albumin, giving the 5.8-to-8.1-day half-life and the multi-day GH/IGF-1 elevation ^{[1] [2]}. The no-DAC form — Modified GRF 1-29 — keeps the four protease-resistant substitutions but lacks the albumin-binding moiety, so it is short-acting, clearing in the minutes-to-hours range like the native GHRH(1-29) fragment it is built on. Same backbone, opposite duration. The half-life of the DAC variant is what most people are actually asking about when they ask how long CJC-1295 lasts.

What the record settles, and what it leaves open

Read straight, the CJC-1295 literature settles three things and leaves the rest open. It settles that a single subcutaneous dose elevates GH and IGF-1 for days in healthy adults ^[1]; that the pituitary's pulsatile rhythm survives the sustained stimulation ^[3]; and that the albumin-conjugation design is what produces the multi-day duration ^[2]. Those are the inscribed, citable facts.

It leaves open almost everything a prospective user would want to know. There is no controlled trial of body composition, strength, recovery, or aging markers; no long-term safety study in healthy adults; and no trial of the popular CJC-1295/ipamorelin pairing for any outcome ^{[1] [3]}. The development history adds caution rather than reassurance: the long-acting DAC program was discontinued, and CJC-1295 is not approved for human use and is prohibited at all times in sport under WADA Section S2. This site is built to hold both halves of that picture at once — the genuine findings and the genuine gaps — without letting either one drown out the other.

What is CJC-1295?

A synthetic GHRH analog built on hGRF(1-29) with four protease-resistant substitutions ^[2]. The DAC variant covalently binds serum albumin for a multi-day half-life, while the no-DAC form (Modified GRF 1-29) is short-acting ^[1]. It stimulates the body's own pulsatile GH release rather than supplying growth hormone directly ^[1].

What does CJC-1295 do?

It binds the GHRH receptor on pituitary somatotrophs, stimulating pulsatile GH release and a downstream rise in hepatic IGF-1 ^[1]. In human studies a single subcutaneous dose raised GH and IGF-1 for days while the pituitary's pulsatile rhythm was preserved ^{[1] [3]}.