CJC-1295 at a glance
The hypothalamus prompts the pituitary to release growth hormone (GH) by sending growth-hormone-releasing hormone, GHRH. The natural hormone is 44 amino acids long, yet residues 1 to 29 carry almost all of its activity. CJC-1295 is that 29-residue piece with four amino acids exchanged so that enzymes degrade it more slowly. It is a synthetic GHRH analogue, the same class as tesamorelin.
Two molecules go by the name. The long-acting one carries a drug affinity complex (DAC) on its C-terminus and is also written DAC:GRF. The short-acting one has the identical sequence without that group and is usually sold as Mod GRF 1-29.
- GHRH(1-29) with four substitutions; the target is the GHRH receptor of the pituitary.
- Half-life of roughly 6–8 days with DAC, minutes without.
- Human data: phase 1 pharmacology in healthy adults, published in 2006. Development was then discontinued.
- King Peptides sells it only as a blend with ipamorelin.
How CJC-1295 works
The receptor sits on the somatotrophs, the GH-producing cells of the anterior pituitary. Binding raises cyclic AMP inside the cell, and GH is both made and secreted. The gland’s own controls stay in charge: somatostatin can still shut secretion down, and IGF-1 still feeds back. Unlike recombinant GH, which bypasses the pituitary, the analogue can only draw out what the gland is prepared to deliver.
Of the four substitutions, the one at position 2 matters most. A D-alanine there stops dipeptidyl peptidase-4 (DPP-4) from cutting the chain, the reaction that inactivates natural GHRH within minutes.
The DAC does the rest. Chemically it is a short spacer ending in a maleimide. In the bloodstream the maleimide forms a covalent bond with cysteine-34 of albumin, the one free thiol on that protein. Riding on albumin, the peptide escapes filtration by the kidney and most peptidases, and the half-life stretches to roughly 6–8 days.
The evidence ladder for CJC-1295
| Evidence level | Model or trial | Main finding |
|---|---|---|
| Animal study | Rodent work on GH secretion patterns (background physiology, not a CJC-1295 trial) | Liver gene expression follows the pulse profile of GH, not the mean level |
| Human pharmacology | Teichman et al. (2006): healthy adults, one subcutaneous dose of the DAC version | Mean GH 2- to 10-fold higher for six days or more; IGF-1 1.5- to 3-fold higher for 9 to 11 days |
| Human pharmacology (class) | 1990s studies combining a GHRH with a GHRP | Considerably more GH released than with either peptide alone |
The ladder ends at phase 1. Teichman and colleagues measured two hormones in volunteers; body composition, strength and wound healing were not endpoints. Development stopped after the early trials, so phase 3 never came and nobody has approved the compound. Statements about longer use are borrowed from GH physiology in general or from tesamorelin, the GHRH analogue with a licensed medicine behind it.
The pulse question is unresolved. GH is normally secreted in bursts, the largest soon after sleep begins, with levels near zero in between. The DAC version lifts the average and fills the gaps; Mod GRF 1-29 adds a single burst and disappears. No published trial has set the two forms side by side.
CJC-1295 doses reported in studies
These are reference values from published work, not guidance. No validated human dose exists for either form.
| Setting | Dose | Schedule | Route | Note |
|---|---|---|---|---|
| Teichman et al. (2006), phase 1, healthy adults | 30, 60, 125 or 250 µg/kg, CJC-1295 with DAC | Single dose | Subcutaneous | GH and IGF-1 read-outs only |
| GHRH stimulation test (diagnostic; sermorelin, plain GHRH(1-29)) | About 1 µg/kg | Once; GH sampled during the following hour | Intravenous | Peak GH shows pituitary reserve; not CJC-1295 |
| Mod GRF 1-29 | None: no published dose-finding study carries this name | – | – | Controlled human data are lacking |
One single-dose study shows what happens to two hormones over ten days. It defines neither a repeat schedule nor a duration. Weekly milligram figures seen on supplier pages do not come from this record and are left out.
Safety findings and open questions
In the phase 1 work, volunteers tolerated the single doses well apart from short-lived reactions at the injection site. Facial flushing after dosing is a recognised effect of GHRH analogues as a class. One dose of the DAC version held IGF-1 above baseline for over a week; where licensed therapies raise IGF-1, it is measured and kept inside the age-adjusted reference range.
Other concerns are inferred from the GH axis, not observed with CJC-1295. GH counteracts insulin, so more GH can mean lower insulin sensitivity; the tesamorelin label warns of glucose intolerance, while CJC-1295 has no glucose data of its own. Swollen limbs, aching joints and carpal tunnel complaints are known from GH excess and GH replacement, but no CJC-1295 trial ran long enough to show them.
- What do IGF-1, glucose and fluid balance do over months of exposure? No long-term dataset exists.
- Does a continuously raised GH level act on tissues differently from added pulses?
- Which of the two molecules is in a given vial? Only the mass spectrum answers reliably.
Bench notes: storing and reconstituting CJC-1295
Keep the lyophilised powder at −20 °C, closed, dry and out of the light. Bring a vial to room temperature before the stopper comes off; condensation on cold powder is an avoidable form of damage.
The shop product is a blend, so any solution made from it contains both peptides, 5 mg of each according to the product name. Bacteriostatic water suits a vial that will be sampled several times. Let the solvent run down the inside of the glass, roll or swirl until the liquid is clear, and never shake. Store solutions in the fridge, protected from light, and freeze single portions for longer work. Details are in the storage and reconstitution protocol.
Status in the Netherlands, Belgium and Luxembourg
EU marketing authorisations come from the European Medicines Agency and apply in the Netherlands, Belgium and Luxembourg alike. CJC-1295 holds none, in the EU or anywhere else. Because development was discontinued, the agency never assessed it and no licensed indication exists. Material sold under the name is a research peptide, not a medicine, and not for human use. National and institutional rules on possession and personal import differ and must be checked.
Section S2 of the WADA Prohibited List names GHRH analogues, in the same section as GH secretagogues and IGF-1 analogues such as IGF-1 LR3. Everything in S2 is prohibited at all times, in competition and out of it. The class is compared in GH secretagogues compared.
Ordering CJC-1295 for research in the Benelux
King Peptides does not list CJC-1295 as a single-peptide vial. The shop sells it as one blend product, CJC-1295 + Ipamorelin Blend 5/5 mg, in which it shares the vial with the ghrelin receptor agonist ipamorelin.
Every lot comes with its own certificate of analysis showing HPLC and mass spectrometry results. The mass tells you which CJC-1295 you have: 3647.2 Da for the DAC form, 3367.9 Da for the form without. The gap of about 280 Da is easy to resolve. A blend certificate should account for both peptides, so expect a second, much lighter mass for ipamorelin. HPLC purity should read 99% or higher, and the lot number must match the vial. Which form a given lot contains cannot be settled here; read the product page, then the certificate. See checking a certificate of analysis.
Orders are dispatched from the Netherlands in a tracked parcel: usually 1–2 business days within the Netherlands, 3–5 business days to Belgium and Luxembourg, no customs clearance inside the EU. The Benelux buying guide lists the supplier checks.
CJC-1295: quick answers
Which version did the 2006 phase 1 study use? The DAC version, as a single subcutaneous dose in healthy adults.
How do I tell the two forms apart on paper? By mass: 3647.2 Da with DAC, 3367.9 Da without. Names on labels are used loosely; the spectrum is not.
Can CJC-1295 be ordered without ipamorelin? Not from King Peptides, which lists only the blend.
Why pair a GHRH analogue with a ghrelin mimetic? They act on different receptors of the same pituitary cell, and human studies from the 1990s found that a GHRH plus a GHRP released considerably more GH than either alone. The background is in peptide combinations.
Is CJC-1295 a medicine anywhere? No. No regulator has assessed it, and the human literature amounts to little more than a single phase 1 report.
Research use only. This page describes CJC-1295 for laboratory and scientific research. Research material has no marketing authorisation, whatever the status of the molecule as a medicine elsewhere, and is not meant for human or veterinary use. Nothing on this page is medical advice; the doses above are those reported in published studies, not recommendations. Check the rules that apply in your country and at your institution before ordering.