What is the difference between CJC-1295 with and without DAC?
The CJC-1295 DAC variant has a ~6-8 day plasma half-life via an N-terminal albumin-binding moiety; CJC-1295 No DAC (modified GRF 1-29) has a ~30-minute half-life without that moiety. DAC produces continuous GHRH-receptor stimulation; No DAC produces pulsatile GH release matching natural pituitary rhythms. Same protease-resistance backbone substitutions, different pharmacokinetic profile.
What the research literature says
Both variants share the core GHRH 1-29 backbone with four protease-resistance amino-acid substitutions (D-Ala, Gln, Ala, Leu at positions 2, 8, 15, 27) that confer resistance to dipeptidyl peptidase IV cleavage. The DAC variant adds an N-terminal maleimidopropionic-acid moiety (the Drug Affinity Complex) that covalently conjugates to circulating serum albumin after subcutaneous administration, extending the plasma half-life from minutes to days.
The original Jetté characterisation paper documented the DAC variant as a long-acting GRF receptor agonist (PMID 15817669). The Teichman clinical-pharmacology work in healthy adults documented prolonged GH and IGF-1 secretion under DAC stimulation (PMID 16352683). The Ionescu pulsatile-GH work examined whether pulsatile GH release persists during continuous DAC stimulation (PMID 17018654), with the finding informing the broader question of how sustained GHRH-receptor agonism interacts with the pituitary’s natural rhythm-generation machinery.
The No DAC variant is functionally distinct because its short half-life supports pulsatile GH release at each dose without the receptor-desensitisation issues that can accompany sustained agonism. The Ronin catalog stocks the No DAC variant; the DAC variant is not in the catalog.
Why this matters in research context
The choice between variants depends on the experimental pharmacology being studied. Research designs targeting sustained GHRH-receptor stimulation use the DAC variant; designs targeting pulsatile GH release (which more closely mirrors the natural pituitary rhythm) use the No DAC variant. Most research-supply protocols favour the No DAC variant because the pulsatile pattern aligns better with physiological GH regulation.
Related compounds
- CJC-1295 No DAC 10mg — the short-acting pulsatile variant in the catalog
- CJC-1295 + Ipamorelin Blend — single-vial combination
Related research questions
- What is the half-life of CJC-1295 No DAC?
- Can CJC-1295 be stacked with ipamorelin?
- What is the half-life of tesamorelin?
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]
- 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]
Research-questions pages 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.