— Research monograph
CJC-1295
A GHRH(1-29) analog supplied in two forms whose durations are not comparable.
- Class
- Synthetic analog of growth-hormone-releasing hormone residues 1 to 29, supplied in two distinct forms: with a Drug Affinity Complex albumin-binding linker, and without it (the form usually labelled modified GRF 1-29)
- Half-life (research)
- Form-dependent, and the distinction matters more here than for most compounds. For the DAC form, Teichman and colleagues estimated 5.8 to 8.1 days in healthy adults, with IGF-1 elevation reported for nine to eleven days after a single administration. For the without-DAC form no comparable validated human figure was traced during preparation of this entry, and none is asserted; the absence of the albumin anchor means its duration is not comparable to the DAC figures and those numbers should not be transferred to it. Stated for interpretation of the literature only.
- Origin
- Developed by ConjuChem in the early 2000s as a long-acting GHRH analog. The defining chemistry is the Drug Affinity Complex: a maleimidopropionyl group that forms a covalent bond with circulating serum albumin after administration, extending plasma residence far beyond that of native GHRH.
- Solubility
- Supplied lyophilised, commonly as the acetate or trifluoroacetate salt. Reported as soluble in water and in aqueous buffers. The DAC form carries a maleimide group, which is thiol-reactive by design and is the chemistry responsible for albumin conjugation; that reactivity is also why the two forms should not be assumed to share handling characteristics. Physicochemical context only. Merit Sciences publishes no reconstitution or preparation procedures.
What is CJC-1295?
CJC-1295 is the name applied to two materials that behave very differently, and conflating them is the most common error in reading this literature. The form carrying the Drug Affinity Complex binds covalently to albumin and persists for days. The form without it, commonly sold and cited as modified GRF 1-29 or CJC-1295 without DAC, carries four amino acid substitutions that resist enzymatic degradation but has no albumin anchor, and its duration of action is on a completely different scale. Published human pharmacokinetics for CJC-1295 refer to the DAC form unless stated otherwise. Merit supplies the without-DAC form co-formulated with ipamorelin.
The principal human study is Teichman and colleagues, published in the Journal of Clinical Endocrinology and Metabolism in 2006: two randomised, placebo-controlled, double-blind ascending-dose trials in healthy adults aged 21 to 61, running 28 and 49 days. After a single administration the investigators reported dose-dependent increases in mean plasma growth hormone of roughly two to ten fold sustained for six days or more, and increases in mean plasma IGF-1 of roughly 1.5 to three fold sustained for nine to eleven days, with an estimated half-life of 5.8 to 8.1 days. After repeated administration mean IGF-1 remained above baseline for up to 28 days, indicating a cumulative effect.
The mechanistic significance of a GHRH analog rather than a direct growth hormone preparation is that secretion remains under pituitary control and retains its pulsatile character, which is the basis for the class being studied at all. Those findings are reported in small enrolled populations under controlled clinical conditions and are summarised here as literature only. Merit Sciences supplies this material strictly for laboratory research use, and publishes no preparation, dosing or administration guidance.
How does CJC-1295 work?
CJC-1295 is described as an agonist at the growth-hormone-releasing hormone receptor on pituitary somatotrophs, a Gs-coupled receptor whose activation raises intracellular cyclic AMP and drives synthesis and pulsatile release of growth hormone, with hepatic IGF-1 rising downstream. The four substitutions in the 1-29 sequence are reported to confer resistance to dipeptidyl peptidase-4 cleavage, which is the principal route of native GHRH degradation. In the DAC form the maleimidopropionyl linker reacts with a free cysteine thiol on serum albumin, producing a circulating depot and the multi-day half-life reported by Teichman and colleagues. Because the analog acts upstream at the pituitary rather than replacing growth hormone directly, negative feedback through somatostatin and IGF-1 remains in the loop, which the literature treats as the distinguishing feature of the class.
Research applications
- GHRH receptor pharmacology and somatotroph signalling
- Growth hormone pulsatility and hypothalamic-pituitary axis models
- Albumin-conjugation and half-life-extension chemistry
- Comparative studies of DAC and non-DAC GHRH analogs
- IGF-1 axis and downstream endocrine research
Form & storage
CJC-1295 ships as a sealed, lyophilized (freeze-dried) powder. Supplied lyophilised, commonly as the acetate or trifluoroacetate salt. Reported as soluble in water and in aqueous buffers. The DAC form carries a maleimide group, which is thiol-reactive by design and is the chemistry responsible for albumin conjugation; that reactivity is also why the two forms should not be assumed to share handling characteristics. Physicochemical context only. Merit Sciences publishes no reconstitution or preparation procedures. Store sealed, light-protected, and follow your institution’s handling procedures for research materials.
Frequently asked questions
What is CJC-1295?
CJC-1295 is the name applied to two materials that behave very differently, and conflating them is the most common error in reading this literature. The form carrying the Drug Affinity Complex binds covalently to albumin and persists for days. The form without it, commonly sold and cited as modified GRF 1-29 or CJC-1295 without DAC, carries four amino acid substitutions that resist enzymatic degradation but has no albumin anchor, and its duration of action is on a completely different scale. Published human pharmacokinetics for CJC-1295 refer to the DAC form unless stated otherwise. Merit supplies the without-DAC form co-formulated with ipamorelin. Merit supplies it as a lyophilized research compound for research use only — not for human or veterinary use.
How does CJC-1295 work?
CJC-1295 is described as an agonist at the growth-hormone-releasing hormone receptor on pituitary somatotrophs, a Gs-coupled receptor whose activation raises intracellular cyclic AMP and drives synthesis and pulsatile release of growth hormone, with hepatic IGF-1 rising downstream. The four substitutions in the 1-29 sequence are reported to confer resistance to dipeptidyl peptidase-4 cleavage, which is the principal route of native GHRH degradation. In the DAC form the maleimidopropionyl linker reacts with a free cysteine thiol on serum albumin, producing a circulating depot and the multi-day half-life reported by Teichman and colleagues. Because the analog acts upstream at the pituitary rather than replacing growth hormone directly, negative feedback through somatostatin and IGF-1 remains in the loop, which the literature treats as the distinguishing feature of the class. Mechanistic descriptions summarize published preclinical findings and are not clinical claims.
What is the half-life of CJC-1295?
Form-dependent, and the distinction matters more here than for most compounds. For the DAC form, Teichman and colleagues estimated 5.8 to 8.1 days in healthy adults, with IGF-1 elevation reported for nine to eleven days after a single administration. For the without-DAC form no comparable validated human figure was traced during preparation of this entry, and none is asserted; the absence of the albumin anchor means its duration is not comparable to the DAC figures and those numbers should not be transferred to it. Stated for interpretation of the literature only. Values reflect preclinical or research-context reports, not clinical pharmacokinetics.
Is Merit CJC-1295 for human use?
No. It is sold strictly for research use only — not for human or veterinary use, and not for diagnostic or therapeutic use. Every batch is tested before it is listed, and its certificate of analysis documenting ≥99% HPLC purity is published in the COA library.
References
- 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. Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA. The Journal of Clinical Endocrinology and Metabolism, 2006 · PMID 16352683
- Activation of the GH/IGF-1 axis by CJC-1295, a long-acting GHRH analog, results in serum protein profile changes in normal adult subjects. Ionescu M, Frohman LA (authorship to be confirmed on validation). Growth Hormone and IGF Research, 2009 · PMID 19386527
For research use only. Not for human or veterinary use. Not FDA-approved. Reference information summarized from published literature — not medical or dosing advice.