CJC-1295: Stretching a GHRH Pulse Across Days

The short version

CJC-1295 is a modified, longer-acting version of GHRH(1-29) — the same fragment sermorelin represents — engineered with four amino-acid substitutions that resist enzymatic breakdown. Its "DAC" (Drug Affinity Complex) form goes a step further: a chemical linker lets it bond permanently to serum albumin in the bloodstream, which is what stretches a single dose's effect from hours to days. A "no-DAC" form (also called Modified GRF 1-29) keeps the protease-resistance but skips the albumin binding, so it clears the body quickly.

CJC-1295 has never been approved for human use anywhere and is sold only as a research chemical. In community reports it shares the sleep and recovery pattern seen across this whole desk, alongside water retention that is described as more pronounced with the long-acting DAC form than with the short-acting no-DAC form.

What it is

CJC-1295 is built on the first 29 residues of human GHRH, hGRF(1-29), carrying four substitutions — D-Ala at position 2, Gln at 8, Ala at 15, and Leu at 27 — that stabilize the peptide's alpha-helix and block the enzymatic cleavage, deamidation, and oxidation that limit unmodified GHRH's stability. In the DAC variant, a C-terminal lysine carries a maleimidopropionyl linker that undergoes a chemical reaction with the free thiol on Cys34 of circulating serum albumin, forming a covalent peptide-albumin conjugate and extending the plasma half-life toward that of albumin itself.

How it works

Like sermorelin, CJC-1295 binds the GHRH receptor on anterior-pituitary somatotrophs, activating cAMP/PKA signaling that stimulates GH synthesis and pulsatile release, which in turn raises hepatic IGF-1. The difference is duration: because the DAC form is covalently bound to albumin, a single dose keeps GH and IGF-1 elevated for days rather than hours, while — notably — the underlying pulsatile pattern of GH secretion is preserved rather than replaced with a flat, continuous elevation.

What the research shows

A 2025 review in Nature Reviews Endocrinology frames CJC-1295 within the broader class of GHRH analogs alongside sermorelin and tesamorelin, describing receptor signaling and the design rationale for long-acting analogs ^[1]. CJC-1295 was structurally identified by high-resolution mass spectrometry as the active ingredient in an unlabeled "GHRH" preparation seized in an anti-doping investigation, confirming it circulates in the gray market ^[13].

In 11 healthy young men, CJC-1295 administration shifted the serum proteome in ways that correlated linearly with IGF-1, identifying candidate biomarkers of GH/IGF-1 axis activation ^[14]. In healthy adults aged 21 to 61, single subcutaneous doses of 30 or 60 micrograms/kg produced dose-dependent, 2- to 10-fold increases in mean plasma GH lasting 6 days or more, and 1.5- to 3-fold increases in IGF-1 lasting 9 to 11 days; after repeated doses, IGF-1 stayed above baseline for up to 28 days, with an estimated CJC-1295 half-life of 5.8 to 8.1 days ^[15]. In healthy men aged 20 to 40, a single subcutaneous dose of 60 or 90 mcg/kg raised trough GH roughly 7.5-fold and mean GH by about 46%, and IGF-1 by about 45%, one week later — while the frequency and size of the body's normal pulsatile GH secretion were unchanged, showing that GH pulsatility persists under continuous GHRH-receptor stimulation from the DAC form ^[16].

Reported effects, cautions & safety

The following community-reported effects are anecdotal, not clinical evidence, and no dose is implied by any of them.

Deeper, more restful sleep is again the single most commonly reported effect, often noticed within the first week. Faster recovery from training, gradual fat loss around the midsection over three to six weeks, and a leaner look with better muscle retention while dieting are all frequently mentioned, usually alongside diet and training rather than as a standalone effect. Improved daytime energy and focus, and firmer-feeling skin and connective tissue, are described occasionally and are often attributed to better sleep rather than a direct effect.

On the adverse side, water retention, bloating, and puffiness are the most commonly reported downside — communities widely describe it as more pronounced with the long-acting DAC form than the short-acting no-DAC form, consistent with DAC keeping GH elevated for days rather than hours. Tingling or numbness in the hands, comparable to mild carpal tunnel and generally attributed to fluid retention, is frequently reported, as are ordinary injection-site reactions. Occasionally reported: brief flushing or a "head rush" right after a no-DAC dose, fatigue or drowsiness (more often with the DAC form), headache, increased appetite (most often when paired with ipamorelin), and — in a subset of self-reports — higher blood sugar or reduced insulin sensitivity with sustained use.

On the cited literature: CJC-1295 has never been approved for human use, and the published human evidence remains limited to the small pharmacology studies above ^[15][16]. Sustained IGF-1 elevation carries a mechanism-based, theoretical cancer concern common to GH-axis compounds, given IGF-1's role in promoting cell growth ^[15]. FDA briefing materials for the 2024 Pharmacy Compounding Advisory Committee cited immunogenicity and other safety concerns as part of the basis for not recommending CJC-1295 for the 503A compounding bulks list. Growth hormone's known tendency to promote fluid retention and to reduce insulin sensitivity is the mechanistic basis for community reports of bloating, carpal-tunnel-like symptoms, and blood-sugar shifts. The original long-acting CJC-1295 DAC development program was discontinued after a Phase 2 trial in HIV-associated visceral obesity; a patient death during that development era is frequently cited alongside the halted trial, though a causal link to CJC-1295 was not established in the public record. CJC-1295 is prohibited in sport at all times under WADA Section S2.

Where it fits in the Growth Hormone Axis

CJC-1295 is sermorelin's own GHRH-receptor mechanism, re-engineered for duration — a single dose reaching across days instead of hours. That makes it the natural GHRH-side partner for ipamorelin's separate ghrelin-receptor pathway, which is exactly the pairing explored on the CJC-1295/ipamorelin page. See the comparison page for the full picture.