CJC-1295: Sustained GH Elevation, Unresolved Safety

The short version

CJC-1295 is a synthetic analog of growth-hormone-releasing hormone (GHRH). It works by binding the GHRH receptor on pituitary cells and telling them to release growth hormone — and because it is engineered to resist breakdown and (in the DAC form) to attach itself to a carrier protein in the blood, a single dose can keep GH and IGF-1 elevated for days rather than minutes.

This is one of the better-pharmacologically-characterized research peptides covered on this desk: two published studies in healthy adult humans have documented its PK/PD in reasonable detail ^[9][10]. The problem is what those studies did not lead to: no Phase 3 trial, no regulatory approval anywhere, and in 2024, FDA briefing materials at the Pharmacy Compounding Advisory Committee cited safety concerns including immunogenicity when reviewing the compound for 503A bulk substance eligibility — and it was not recommended for inclusion ^[6]. It remains a research chemical, it is banned in sport, and its long-term safety in people is simply unknown. This page does not recommend a dose or protocol.

What it is

CJC-1295 is built on the first 29 residues of human growth-hormone-releasing factor, hGRF(1-29), with four amino-acid substitutions: D-Ala at position 2 blocks dipeptidylpeptidase-IV cleavage, Gln at 8 resists deamidation, Ala at 15 stabilizes the alpha-helix, and Leu at 27 prevents oxidation. Together these substitutions extend the plasma half-life from minutes to hours.

In the DAC (Drug Affinity Complex) variant, a C-terminal lysine carries a maleimidopropionyl linker that covalently binds to Cys34 on circulating serum albumin — extending the effective half-life to 5-8 days, approximating albumin's own lifespan ^[9]. The no-DAC form (also called Modified GRF 1-29) keeps the four substitutions but lacks the albumin-binding moiety and is short-acting (hours).

These two forms behave very differently in terms of GH elevation duration, fluid retention, and sustained IGF-1 exposure — and they are routinely conflated in marketing and online discussion ^[6].

CJC-1295 has never been approved by the FDA, EMA, or any major regulatory authority. It is not on the 503A compounding bulk substances list. It is a research chemical.

How it works

CJC-1295 binds the growth-hormone-releasing hormone receptor (GHRHR) on anterior-pituitary somatotrophs, activating Gs-protein/cAMP/PKA signaling that stimulates both synthesis and pulsatile secretion of growth hormone. GH in turn acts on the liver and peripheral tissues to raise IGF-1.

A critical finding from the human PK studies is that pulsatile GH secretion is preserved even under continuous GHRHR stimulation by CJC-1295 DAC. In healthy 20- to 40-year-old men given a single subcutaneous dose (60 or 90 µg/kg), the frequency and magnitude of individual GH pulses were unaltered one week later — basal GH rose approximately 7.5-fold and mean GH by ~46%, but pulsatility remained intact ^[10]. This is mechanistically important: CJC-1295 amplifies the baseline rather than replacing it with a flat wave.

A 2025 Nature Reviews Endocrinology review of GHRH and its analogs provides the current authoritative framing of receptor signaling, the rationale for long-acting analog design, and their evolving therapeutic and investigational landscapes ^[6].

What the research shows

Human PK/PD — multi-day GH and IGF-1 elevation. In healthy adults across a broad age range (21-61 years), single subcutaneous doses of 30 or 60 µg/kg CJC-1295 produced dose-dependent 2- to 10-fold increases in mean plasma GH sustained for 6 or more days, and 1.5- to 3-fold increases in IGF-1 sustained for 9 to 11 days. After multiple doses, IGF-1 remained above baseline for up to 28 days, with an estimated CJC-1295 half-life of 5.8 to 8.1 days ^[9].

Pulsatility preservation. In healthy men (20-40 years old), a single dose of 60 or 90 µg/kg raised basal GH ~7.5-fold and mean GH ~46% and IGF-1 ~45% one week later, with pulsatile GH secretion pattern unchanged ^[10]. The GH axis amplifies but does not lose its rhythmic architecture.

Serum proteome shift. In 11 healthy young men, CJC-1295 administration shifted the serum proteome detectably: decreased apolipoprotein A1 and a transthyretin isoform; increased an albumin C-terminal fragment and immunoglobulin species. The immunoglobulin/albumin-fragment signal correlated linearly with IGF-1, identifying candidate biomarkers of GH/IGF-1 axis activation ^[8].

Anti-doping identification. CJC-1295 was structurally identified by high-resolution LC-MS/MS as the active ingredient in an unknown 'GHRH' pharmaceutical preparation seized in an anti-doping context — confirming both its prevalence in the sports-doping landscape and its detectability ^[7].

The development history. The original long-acting DAC program ran a Phase 2 trial in HIV-associated visceral obesity that was discontinued. A patient death during the development era is frequently cited in connection with the halted program; the public record does not establish a causal link to CJC-1295. The compound never advanced to Phase 3 or approval ^[6].

Reported effects, cautions & safety

Research-use communities report extensively on CJC-1295, particularly the DAC versus no-DAC comparison. All of the following are anecdotal, not clinical evidence — reports from individuals using research-grade material without medical supervision.

Very commonly reported anecdotal benefits: deeper and more restful sleep, often noted within the first week (fits the known biology, as GH release tracks deep sleep). Faster recovery between training sessions.

Frequently reported anecdotal benefits: gradual fat loss, most often reported around the midsection and emerging around weeks three to six. Leaner appearance and perceived better muscle retention while dieting. Effects are consistently described as slow and subtle.

Occasionally reported anecdotal benefits: more daytime energy (often attributed to sleep quality), improved focus and mental clarity, firmer skin or improved connective-tissue feel over weeks.

Very commonly reported anecdotal adverse effects: water retention and puffiness, described as most pronounced with the long-acting DAC form. Communities widely note this is the dominant downside, particularly in the face and hands.

Frequently reported anecdotal adverse effects: tingling or pins-and-needles in the fingers (attributed to fluid retention), injection-site redness and itching.

Occasionally reported anecdotal adverse effects: flushing or head-rush (more with no-DAC, shortly after injection), fatigue or sluggishness (more commonly reported with DAC), headache, increased appetite (particularly when used with ipamorelin, attributed to the ipamorelin partner), higher blood sugar or reduced insulin sensitivity (reported most in self-experiments with prolonged use).

Evidence-based cautions:

• Immunogenicity: The FDA's 2024 PCAC briefing cited immunogenicity as a safety concern for GH secretagogues including CJC-1295, alongside a 2025 pharmacology review that reinforces this for long-acting albumin-binding designs ^[6].
• Sustained IGF-1 elevation: Prolonged IGF-1 elevation carries a mechanism-based theoretical cancer concern. The long-acting DAC form creates days of elevated IGF-1 per dose, maximizing the exposure window.
• Fluid retention and nerve compression: GH promotes renal sodium and water retention; this is the mechanistic driver of the commonly reported swelling and carpal-tunnel-like tingling ^[9].
• Blood sugar effects: GH is glucose-sparing; sustained GH axis stimulation can reduce insulin sensitivity — a particular concern for anyone with prediabetes or diabetes.
• DAC vs. no-DAC confusion: These forms are pharmacokinetically very different, yet they are frequently sold under confusingly similar names. The risks of each track their duration of action ^[9][10].
• Prohibited in sport. CJC-1295 is banned at all times under WADA Section S2. Reliable LC-MS/MS and immuno-PCR detection methods exist ^[7].

Where it fits in the growth-hormone axis research

CJC-1295 sits mechanistically opposite to Ipamorelin in the GH secretagogue landscape: where ipamorelin targets the ghrelin receptor to produce a brief, selective GH pulse, CJC-1295 targets the GHRH receptor to produce sustained multi-day GH and IGF-1 elevation. The two classes are complementary, which is why combination protocols appear in the research literature — though no controlled human trial of the combination has been published.

Against NAD+ and MOTS-c, CJC-1295 is a top-of-axis hormonal intervention; NAD+ and MOTS-c operate at the intracellular metabolic level. Together they frame two different intervention points in the biology of aging. Compare all four on the compare page.