CJC-1295 No DAC — also known as modified GRF 1-29 (mod-GRF 1-29) — is a synthetic 29-amino-acid analogue of human growth hormone-releasing hormone with four amino-acid substitutions that confer protease resistance, but without the Drug Affinity Complex (DAC) albumin-binding moiety carried by the long-acting CJC-1295 DAC variant. Shorter half-life than the DAC form, agonist at the GHRH receptor on pituitary somatotroph cells.
Definition
The compound corresponds to the first 29 amino acids of human GHRH (the minimum sequence required for full agonist activity at the GHRH receptor) with four amino-acid substitutions at positions 2, 8, 15, and 27 (D-Ala, Gln, Ala, Leu) that confer resistance to dipeptidyl peptidase IV cleavage at the N-terminus and to other proteolytic-degradation pathways that limit native GHRH’s plasma half-life. The “No DAC” designation distinguishes the variant from CJC-1295 DAC, which adds an N-terminal maleimidopropionic-acid moiety that covalently conjugates to circulating serum albumin after subcutaneous administration, extending the plasma half-life from hours to days.
The No-DAC variant retains the protease-resistant N-terminal modifications but lacks the albumin-binding component. Plasma half-life in the No-DAC form is intermediate between native GHRH (minutes) and the DAC form (multi-day) — typically reported in the order of 30 minutes to a few hours depending on the experimental system. The shorter half-life supports pulsatile-like GH release patterns rather than the sustained elevation produced by the DAC variant.
How CJC-1295 No DAC and CJC-1295 DAC are studied in peptide research
The CJC-1295 published research literature centres predominantly on the DAC variant, which carries the more pronounced pharmacokinetic profile and was the original compound advanced through clinical development. The Jetté characterisation paper identified CJC-1295 (DAC form) as a long-acting GRF analogue activating the GRF receptor on the anterior pituitary (PMID 15817669). Subsequent clinical-pharmacology work in healthy adults documented prolonged stimulation of GH and IGF-1 secretion (PMID 16352683), GHRH-knockout mouse normalization (PMID 16822960), and the question of whether pulsatile GH secretion persists during continuous GHRH-receptor stimulation (PMID 17018654). Serum protein profile changes from sustained GH/IGF-1 axis activation were characterised by Sackmann-Sala (PMID 19386527).
The No-DAC variant is the form most commonly used in research-supply contexts where shorter-acting pulsatile GHRH activity is desired. Direct head-to-head published comparisons between the two variants are limited; the research community typically extrapolates from the DAC-variant clinical data with attention to the substantially different pharmacokinetic profile. Both variants act upstream of the growth hormone receptor via endogenous GH release from the pituitary.
Related terms
- Growth hormone receptor
- Tesamorelin (full-length GHRH analogue)
- Ipamorelin (ghrelin-receptor agonist, distinct mechanism)
- GHRH / growth hormone-releasing hormone
- Modified GRF 1-29 (mod-GRF 1-29) — alias for CJC-1295 No DAC
- Drug Affinity Complex (DAC)
- Dipeptidyl peptidase IV (DPP-IV)
Where CJC-1295 No DAC appears in the Ronin catalog
- CJC-1295 No DAC 10mg — single-compound vial, lyophilized white powder under inert gas
- CJC-1295 + Ipamorelin blend — single-vial co-formulation pairing CJC-1295 No DAC with ipamorelin for combined GHRH-and-ghrelin-receptor research workflows
References
- Jetté L et al. Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analog. Endocrinology 2005;146(7):3052-3058. [PMID 15817669]
- 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;91(3):799-805. [PMID 16352683]
- Alba M et al. Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout mouse. Am J Physiol Endocrinol Metab 2006;291(6):E1290-E1294. [PMID 16822960]
- 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;91(12):4792-4797. [PMID 17018654]
- Sackmann-Sala L et al. 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. Growth Horm IGF Res 2009;19(6):471-477. [PMID 19386527]
Glossary entries describe research-context use of peptide-research terminology. They do not constitute medical, veterinary, or clinical advice. CJC-1295 No DAC is sold strictly as a research-grade reagent for laboratory and bench research applications.