CJC-1295 is a long-acting GHRH analog that sustains growth hormone while preserving its natural pulse.

What is CJC-1295?

CJC-1295 is a synthetic, long-acting analog of growth-hormone-releasing hormone (GHRH). It is built on hGRF(1-29) — the first 29 residues of human GH-releasing factor, the minimal sequence that retains full GH-releasing activity — and carries four amino-acid substitutions (D-Ala at position 2, Gln at 8, Ala at 15, Leu at 27) that stabilize the molecule against dipeptidylpeptidase-IV cleavage, deamidation, and oxidation ^[2]. The variant that gives CJC-1295 its multi-day duration adds a Drug Affinity Complex (DAC): a maleimide linker that covalently binds the peptide to circulating serum albumin, extending its plasma half-life toward that of albumin itself ^[2].

There are two forms, and conflating them is the single most common error about this compound. The DAC variant is the multi-day species, with an estimated half-life of 5.8 to 8.1 days in healthy adults ^[1]. The no-DAC form — usually sold as DAC vs no-DAC half-life, or "Modified GRF 1-29" — keeps the four substitutions but lacks the albumin-binding moiety, so it clears in minutes to hours. They are pharmacokinetically very different molecules wearing nearly the same name ^[1].

Mechanistically, CJC-1295 binds the GHRH receptor on anterior-pituitary somatotrophs, activating Gs/cAMP/PKA signaling that drives GH gene transcription and pulsatile GH release; the released GH then raises hepatic IGF-1 through JAK2/STAT5 ^[3]. It is not a steroid and not a growth hormone — it acts one step upstream, asking the pituitary to release more of its own GH. This site documents what the peer-reviewed record actually measured, not what forums claim it does.

CJC-1295 as a synthetic GHRH-analog peptide

CJC-1295 is a single peptide, not a blend. As a synthetic GHRH-analog peptide it belongs to the same molecular family as the hypothalamic hormone GHRH, which the body uses to tell the pituitary when to release growth hormone ^[14]. The four protease-resistant substitutions are what separate it from native GHRH(1-29): native GHRH is cleaved within minutes by dipeptidylpeptidase-IV, while the substituted analog survives that enzyme and stays active far longer ^[2].

The "CJC-1295" name is most precisely attached to the DAC-conjugated, albumin-binding form, which is the lead molecule the original Endocrinology paper identified as a long-lasting GRF analog ^[2]. The structure has a documented CAS number (863288-34-0) and a molar mass near 3367.9 Da before albumin conjugation; after the DAC links to albumin, the species actually circulating in plasma is the much larger peptide-albumin complex of roughly 66 kDa ^[2]. None of this involves an anabolic steroid pathway — the molecule is a peptide secretagogue, and its entire effect is mediated through the GHRH receptor.

Where CJC-1295 sits among GHRH analogs

CJC-1295 is one of several GHRH analogs, and its closest approved relatives are sermorelin and tesamorelin — both built on the same hGRF(1-29) backbone, both acting on the same pituitary receptor ^[14]. A 2024/2025 Nature Reviews Endocrinology review of GHRH and its synthetic analogs maps this class in detail, covering receptor signaling, the design rationale for long-acting analogs, and the therapeutic and investigational landscape that CJC-1295 sits within ^[14].

What distinguishes CJC-1295 inside the class is duration. Sermorelin is short-acting; tesamorelin is an approved daily GHRH analog for HIV-associated lipodystrophy. CJC-1295 DAC was engineered to push duration much further through albumin conjugation, which is why a single dose elevates GH and IGF-1 for days rather than hours ^[1]. The class is also a recurring subject in aging research: a 2026 review of therapeutic peptides in gerontology situates GHRH analogs in the longevity conversation, reflecting the long-standing interest in the age-related decline of the GH/IGF-1 axis ^[15]. CJC-1295 itself, however, remains an unapproved research chemical.

What the GH and IGF-1 data show, in one screen

The headline numbers come from early human pharmacokinetic work. In healthy adults, single subcutaneous doses of 30 or 60 micrograms per kilogram produced dose-dependent 2- to 10-fold increases in mean plasma GH lasting six days or more, and 1.5- to 3-fold increases in IGF-1 lasting nine to eleven days; after repeat dosing, IGF-1 stayed above baseline as long as 28 days ^[1]. The estimated CJC-1295 half-life from that study was 5.8 to 8.1 days ^[1].

The finding that defines this site is about rhythm, not just amount. In healthy men aged 20 to 40, a single dose of 60 or 90 micrograms per kilogram raised basal GH about 7.5-fold and IGF-1 about 45% one week later — while the frequency and magnitude of pulsatile GH secretion were unaltered ^[3]. In plain terms: a continuous, long-acting stimulus raised the floor without flattening the waveform. The pulse train kept running on top of a higher baseline. That result is what the floating pulse motif on this page represents, and it is why CJC-1295 is studied as a GHRH analog rather than as a direct GH injection.

From here, the record branches into the topics this console tracks: the GH and IGF-1 findings in full, the DAC vs no-DAC half-life split, the doses used in CJC-1295 research, the CJC-1295 and ipamorelin synergy rationale, and the CJC-1295 side effects and concerns. Every figure resolves to the full reference list.