Mechanism
CJC-1295 is a synthetic analog of growth hormone-releasing hormone (GHRH) — specifically, a modified version of GRF(1-29), the bioactive fragment of native GHRH. The native fragment has a half-life of minutes; the modifications extend that.
Two distinct forms circulate in the gray-market peptide community, and they’re not interchangeable:
CJC-1295 with DAC (Drug Affinity Complex):
- Adds a maleimidopropionic acid (MPA) linker to the C-terminus
- The MPA covalently bonds to serum albumin in vivo
- Half-life ~6–8 days
- Sustained GH-secretion-inducing effect over multiple days
- This is the form most commonly sold as “CJC-1295”
CJC-1295 without DAC (Mod GRF 1-29):
- Same modifications to GRF(1-29) but without the DAC linker
- Half-life ~30 minutes (similar to native GHRH)
- Pulsatile effect requiring multiple daily injections
- Sometimes marketed as a “more physiologic” alternative since native GHRH is also pulsatile
Both forms work by binding the GHRH receptor on anterior pituitary somatotrophs, stimulating endogenous GH secretion. They preserve the natural GH pulse architecture (more or less) rather than replacing GH directly — distinct from injecting recombinant human GH.
What the evidence shows
The published human PK study (Teichman SL et al, J Clin Endocrinol Metab 2006):
A 49-subject Phase 1 in healthy adults, single-dose CJC-1295 with DAC at 30, 60, 125, or 250 mcg/kg subcutaneous. Showed:
- Sustained elevation of GH (2–10×) for 6+ days post-injection
- Sustained elevation of IGF-1 (1.5–3×) for 9–11 days
- Half-life ~5.8–8.1 days
- Generally well-tolerated at single doses; injection-site reactions most common adverse event
This is the foundational data and the reason CJC-1295 has more credibility than most gray-market peptides in this space.
The gap:
- No published efficacy trials for body composition, athletic performance, sleep quality, or longevity outcomes
- No long-term safety trials with multi-dose chronic exposure
- The pharmaceutical sponsor (ConjuChem) discontinued development for the original intended indications (HIV-associated lipodystrophy, growth hormone deficiency) in the late 2000s — not because the molecule failed, but because the company pivoted strategy
Why this matters for the verdict:
We have evidence that the molecule does what it’s claimed to do at the receptor level (induces sustained GH/IGF-1 elevation). We do not have evidence that doing this produces the clinical outcomes users want, or that doing it chronically is safe.
Dosing literature
There is no approved dose. Gray-market protocols typically use:
With DAC: 0.5–2 mg per week (single subcutaneous injection, often divided as 0.5–1 mg twice weekly)
Without DAC: 100–300 mcg per dose, 1–3 times daily; some protocols stack with ipamorelin to combine GHRH and GHRP effects
The “with DAC + ipamorelin pre-bed” stack is the most common user pattern. The mechanistic logic (GHRH agonist + GHRP agonist drives larger GH pulses than either alone) is reasonable; the human evidence for the stack is anecdotal.
Risks and adverse events
Reported in clinical and gray-market use:
- Injection-site reactions
- Flushing
- Headache
- Tingling / paresthesia
- Water retention
- Insulin resistance with sustained use (consistent with chronic GH elevation)
Less common:
- Joint pain / carpal tunnel symptoms (class-typical of GH-axis manipulation)
- Fatigue
- Mood changes
Theoretical / long-term concerns:
- Cancer promotion — the IGF-1 elevation that CJC-1295 produces is the same pathway concern flagged for IGF-1 LR3, less acute because the elevation is more modest, but cumulative chronic exposure is the variable that matters
- Diabetic retinopathy — IGF-1 elevation is a known driver
- Acromegaly-like changes — possible with very long-term high-dose use
Quality concerns specific to gray-market product:
The with-DAC and without-DAC versions are sometimes mislabeled or substituted by sellers. They have radically different pharmacokinetics and dosing protocols — confusing them is a real harm vector. Mass-spectrometry analysis of gray-market CJC-1295 samples has found incorrect sequences and contamination at rates comparable to other gray-market peptides.
Regulatory status
| Region | Status | Notes |
|---|---|---|
| United States | Not approved | “Research chemical” status; sale for human use is prohibited. |
| European Union | Not approved | |
| United Kingdom | Not approved | |
| Canada | Not approved | |
| Australia | Schedule 4 | Prescription-only; not commercially available. |
| WADA | Prohibited (S2 — Peptide Hormones) | Banned in competitive sport at all times. |
Where to get it
We do not route readers to a fulfillment partner for CJC-1295. The combination of unapproved regulatory status, gray-market quality variance (worsened by the with-DAC/without-DAC labeling confusion), and absence of efficacy data for the indications it’s marketed for puts it outside what we’ll endorse.
(See How we make money — the absence of a partner link is a deliberate signal.)
References (selected)
- Teichman SL et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab 2006. PubMed
- Ionescu M, Frohman LA. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. J Clin Endocrinol Metab 2006.
- Sackmann-Sala L, Berryman DE, Munn RD, Lubbers ER, Kopchick JJ. Heterogeneity among white adipose tissue depots in male C57BL/6J mice. Obesity 2012 — relevant for understanding GH-axis effects on body composition.
- WADA Prohibited List — Section S2 — current revision.
Quick Facts
| Also Known As | DAC:GRF 1-29, Modified GRF (1-29), Drug Affinity Complex-Growth Hormone Releasing Factor (1-29), CJC-1295 (DAC:GRF) |
|---|---|
| Sequence | Tyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg |
| Molecular Formula | C165H269N47O46 |
| Molecular Weight | 3647.2 Da |
| PubChem CID | 91971820 |
Research Parameters
| Half-Life | ~6-8 days in humans (after albumin binding). |
|---|---|
| Stability | Lyophilized powder is stable for at least 24 months when stored at -20°C, protected from light and moisture. After reconstitution in bacteriostatic water, the solution should be stored at 2-8°C and is typically stable for 28-30 days. Repeated freeze-thaw cycles of the reconstituted solution are not recommended. |
| Solubility | Bacteriostatic Water (0.9% benzyl alcohol) or Sterile Water for Injection. Bacteriostatic water is preferred for multi-dose use due to its preservative. |
| Vial Size | 2 mg |
| Storage (Lyophilized) | -20°C or below, protected from light and moisture. |
| Storage (Reconstituted) | 2-8°C (refrigerated), protected from light. Do not freeze. |
| Typical Research Dose | 30-60 mcg/kg (based on clinical trial protocols). |
| Cycle Parameters | In research protocols, typically administered via subcutaneous injection 1-2 times per week. Study durations have ranged from single-dose pharmacokinetic assessments to continuous administration for 12 weeks. |
| Amino Acid Count | 30 |
Mechanism of Action
CJC-1295 acts as a potent agonist of the Growth Hormone-Releasing Hormone Receptor (GHRH-R) in the anterior pituitary gland. Its primary mechanism is to stimulate the synthesis and pulsatile secretion of endogenous growth hormone (GH), which in turn mediates its effects via the stimulation of Insulin-like Growth Factor 1 (IGF-1) production primarily in the liver.
GHRH Receptor Activation: Upon binding to the GHRH-R on somatotroph cells in the pituitary, CJC-1295 activates the Gαs protein, leading to increased intracellular cyclic AMP (cAMP). Elevated cAMP activates protein kinase A (PKA), which stimulates GH gene transcription and the release of stored GH secretory granules.
Albumin Binding and Prolonged Action: The key feature of CJC-1295 is its DAC modification. After subcutaneous injection, the maleimide group reacts with the free thiol group of cysteine-34 on endogenous albumin, forming a stable covalent bond. This conjugation dramatically increases the peptide's molecular size and protects it from rapid renal clearance and enzymatic degradation, resulting in a plasma half-life extended to approximately 6-8 days in humans.
Endogenous GH/IGF-1 Axis Stimulation: The sustained presence of CJC-1295 leads to a prolonged, pulsatile stimulation of the pituitary. This results in increased amplitude and possibly frequency of endogenous GH pulses, which then stimulates hepatic production of IGF-1. The activity is subject to the negative feedback loops of the GH axis, including somatostatin and IGF-1 itself, which helps maintain physiological patterns.
Research Applications
Growth Hormone Deficiency (GHD) Research: CJC-1295 has been investigated as a potential therapeutic for adult and pediatric GHD. Studies have shown its ability to significantly increase IGF-1 levels and maintain them within the normal range for over a week after a single injection, suggesting utility in reducing injection frequency compared to daily GHRH analogs.
Anti-Aging and Body Composition Research: In aging research, the decline of GH secretion (somatopause) is associated with increased adiposity, decreased muscle mass, and reduced bone density. Research with CJC-1295 focuses on its ability to safely elevate IGF-1 levels in older adults, with studies examining outcomes on lean body mass, fat mass, strength, and quality of life parameters.
Metabolic Syndrome and Lipid Research: Due to the metabolic effects of GH, CJC-1295 has been studied in contexts of obesity and metabolic syndrome. Research explores its impact on lipid profiles, insulin sensitivity, and visceral adiposity, as GH promotes lipolysis and reduces trunk fat.
Tissue Repair and Wound Healing Research: The GH/IGF-1 axis plays a crucial role in anabolism and tissue regeneration. Preliminary research investigates the potential of CJC-1295 to enhance wound healing, muscle repair after injury, and recovery from surgical stress by providing a sustained anabolic signal.
Safety & Side Effects
Data from limited human clinical trials indicate that CJC-1295 is generally well-tolerated. The most commonly reported side effects are mild and transient at the injection site (e.g., erythema, pruritus, swelling). Systemic side effects reported in studies include occasional headaches, flushing, and dizziness. No serious adverse events were attributed to the drug in published trials.
Theoretical concerns based on the mechanism of action include the potential for acromegaly-like symptoms with chronic overdosing, due to sustained elevation of GH and IGF-1. There is also a theoretical risk of impacting glucose metabolism, as GH can induce insulin resistance, although significant hyperglycemia was not a prominent finding in initial studies. Anecdotal reports from non-clinical use sometimes mention joint pain, fluid retention, or carpal tunnel syndrome, which are known effects of elevated GH, but these are not consistently documented in the controlled literature.
Dosage Information
Disclaimer: The following information is derived from published research studies and is for research purposes only. It does not constitute medical advice.
In human clinical trials, CJC-1295 has been administered via subcutaneous injection. Typical research doses range from 30 mcg/kg to 60 mcg/kg per injection. In key phase I/II studies, doses of 30 mcg/kg and 60 mcg/kg were used. The frequency of administration is significantly reduced compared to unmodified GHRH analogs due to its long half-life; dosing intervals in studies have ranged from once weekly to once every two weeks. The duration of administration in clinical trials has varied from single-dose pharmacokinetic studies to repeated dosing over several weeks (e.g., 12-week treatment periods).
References
Teichman, S.L., et al. 'Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults.' Journal of Clinical Endocrinology & Metabolism, vol. 91, no. 3, 2006, pp. 799-805.
Jetté, L., et al. 'hGRF1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats.' Peptide Science, vol. 80, no. 4, 2005, pp. 367-375.
Clemmons, D.R. 'The relative roles of growth hormone and IGF-1 in controlling insulin sensitivity.' Journal of Clinical Investigation, vol. 113, no. 1, 2004, pp. 25-27.
Gianotti, L., et al. 'Effects of recombinant human growth hormone on inflammatory and metabolic outcomes in adults undergoing major surgery: A systematic review.' Critical Care Medicine, vol. 35, no. 10, 2007, pp. 2410-2419.
Van der Lely, A.J., et al. 'Long-term treatment of acromegaly with pegvisomant, a growth hormone receptor antagonist.' The Lancet, vol. 358, no. 9295, 2001, pp. 1754-1759. (For context on GH axis).
Klinger, B., et al. 'Comparative pharmacokinetics of two sustained-release GHRH analogs in children with idiopathic growth hormone deficiency.' Hormone Research, vol. 62, no. 6, 2004, pp. 287-292.