CJC-1295

CJC-1295 is a synthetic GHRH (Growth Hormone-Releasing Hormone) analogue composed of 30 amino acids, derived from natural GHRH(1-29) with four stabilising substitutions: D-Ala2, Gln8, Ala15, Leu27. These modifications confer resistance to DPP-4 (dipeptidyl-peptidase 4) degradation and plasma endopeptidases, extending native GHRH plasma half-life (~7 minutes) to approximately 30 minutes for DAC-less CJC-1295 (identical to long sermorelin) and 6-8 days for DAC-equipped CJC-1295 (CAS 863288-34-0).

Key difference: DAC vs no-DAC. The Drug Affinity Complex (DAC) is a maleimido-propionyl-lysine group added at the C-terminus that spontaneously reacts by Michael addition with the Cys34 free thiol of serum albumin, forming a covalent thioether adduct. This albumin-peptide binding drastically extends half-life (6-8 days vs 30 min) by removing the peptide from glomerular filtration and proteolysis. DAC-less CJC-1295 preserves physiological pulsatility (GH peak, basal return), while DAC-equipped CJC-1295 causes continuous stimulation (GH-bleed) with sustained IGF-1 elevation and loss of pulsatility.

Mechanism of action. Like all GHRH analogues, CJC-1295 activates the GHRH-R receptor (class B1 GPCR, Gαs coupling → adenylate cyclase → cAMP → PKA → CREB) expressed on pituitary somatotropes, inducing GH1 gene transcription, GH synthesis and secretion, with secondary effects on hepatic IGF-1 and IGFBP-3.

Stack and research uses. CJC-1295 is frequently studied in combination with a GHRP (ipamorelin, GHRP-2, GHRP-6, hexarelin) to exploit cAMP + Ca²⁺ synergy. Study models include lit/lit (GHRH-R dwarfism mouse), ovariectomy-osteoporosis, mdx dystrophy, cachexia and ageing. Reference study: Teichman 2006 J Clin Endocrinol Metab (primate). Lab Peptides France offers CJC-1295 with DAC and without DAC as RUO, with an HPLC ≥ 98% specification.