Research Peptide · For laboratory research use only
Also known as Modified GRF (1-29), Mod GRF 1-29, CJC-1295 No DAC
CJC-1295 without DAC, also called modified GRF (1-29) or Mod GRF 1-29, is a 29-residue, C-terminally amidated analogue of human growth hormone-releasing factor (GRF) 1-29 with four substitutions: D-alanine at position 2, glutamine at 8, alanine at 15 and leucine at 27. This tetrasubstituted hGRF(1-29) is the peptide backbone of CJC-1295 as first described1.
The name causes confusion. In its original description, CJC-1295 carried an additional C-terminal lysine bearing a maleimidopropionamide group, the drug affinity complex (DAC), which binds covalently to serum albumin1. The peptide catalogued here lacks that group. Peer-reviewed literature on the no-DAC peptide itself is limited, and much of it comes from analytical and anti-doping laboratories3,4,5.
As described in the research literature
As described in the research literature, GRF analogues act on the GRF receptor of the anterior pituitary to stimulate growth hormone secretion. In the study that introduced CJC-1295, hGRF(1-29) derivatives were tested for stability against dipeptidyl peptidase-IV and for growth hormone release from cultured rat anterior pituitary cells and in rats1. The albumin-binding DAC group, absent from this peptide, was the feature that extended plasma half-life in that work1.
In 2010, high-resolution mass spectrometry of a seized preparation identified a 29-residue, C-terminally amidated peptide marketed as CJC-1295, that is, the form without the DAC lysine3.
What published studies have examined
Maleimido derivatives of hGRF(1-29) were compared for stability against dipeptidyl peptidase-IV, growth hormone release from rat pituitary cells and plasma persistence in rats, leading to the selection of CJC-12951.
Sources [1]
For comparison, the albumin-binding DAC form has been studied in GHRH knockout mice, where body weight and length, bone length, body composition and pituitary GH mRNA were examined2. Findings for the DAC form do not transfer directly to the peptide catalogued here.
Sources [2]
Mass spectrometry was used to identify the peptide in a seized preparation3 and to detect a glycine-extended variant of modified GRF (1-29) in seized doping material4. In vitro metabolites of CJC-1295 with and without DAC were characterised and used to develop a urine detection method5.
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.
Jetté L, Léger R, Thibaudeau K, et al. Endocrinology, 2005.
Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout mouse.
Alba M, Fintini D, Sagazio A, et al. American Journal of Physiology. Endocrinology and Metabolism, 2006.
Identification of CJC-1295, a growth-hormone-releasing peptide, in an unknown pharmaceutical preparation.
Henninge J, Pepaj M, Hullstein I, et al. Drug Testing and Analysis, 2010.
Glycine-modified growth hormone secretagogues identified in seized doping material.
Gajda PM, Holm NB, Hoej LJ, et al. Drug Testing and Analysis, 2019.
Advances in the detection of growth hormone releasing hormone synthetic analogs.
Memdouh S, Gavrilović I, Ng K, et al. Drug Testing and Analysis, 2021.
This page is provided for research and educational reference only. It does not constitute medical advice, dosing guidance, or a recommendation for use. All compounds are strictly for laboratory and in-vitro research purposes.