What Is CJC-1295?
CJC-1295 with DAC is a tetrasubstituted 30-amino acid peptide hormone (molecular formula C₁₆₅H₂₆₉N₄₇O₄₆) that functions as a GHRH analog, developed by ConjuChem Biotechnologies to overcome natural GHRH's extremely short half-life of approximately 7 minutes. CJC-1295 without DAC (Mod GRF 1-29) is a distinct 29-amino acid peptide with the molecular formula C₁₅₂H₂₅₂N₄₄O₄₂. Both produce sustained, dose-dependent increases in both GH and IGF-1 without significantly altering other pituitary hormones such as prolactin, FSH, LH, or TSH.
Two Primary Forms:
CJC-1295 with DAC (Drug Affinity Complex): The DAC modification enables covalent binding to serum albumin after injection, extending its half-life to 5.8–8.1 days. This allows once or twice weekly dosing and produces more sustained elevation of GH and IGF-1 levels.
CJC-1295 without DAC (Modified GRF 1-29 / Mod GRF): Has a half-life of approximately 30 minutes, requiring multiple daily injections. It more closely mimics the body's natural pulsatile GH release pattern, which some researchers believe better reflects natural physiology.
How It Works
GHRH Receptor Activation
CJC-1295 mimics the action of endogenous growth hormone-releasing hormone by binding to GHRH receptors on somatotroph cells in the anterior pituitary gland. This triggers synthesis and secretion of growth hormone while preserving natural feedback systems, unlike exogenous GH administration which suppresses endogenous production.
Extended Half-Life Through Albumin Binding
DAC technology represents a significant pharmacological advancement. After subcutaneous injection, CJC-1295 with DAC forms a covalent bond with circulating albumin through a reactive maleimido group, protecting the peptide from enzymatic degradation and renal clearance. Research confirmed an estimated half-life of 5.8–8.1 days in healthy adults.
Pulsatile vs. Sustained GH Release
CJC-1295 without DAC produces a more pulsatile pattern of GH release, which some researchers believe better mimics natural physiology. The body normally releases GH in pulses, with the largest occurrence during deep sleep. CJC-1295 with DAC creates more sustained elevation of GH and IGF-1 levels, which may benefit certain therapeutic applications but potentially blunts the natural pulsatile rhythm.
IGF-1 Axis Activation
Beyond direct GH stimulation, CJC-1295 activates the broader GH/IGF-1 axis. Elevated GH stimulates the liver to produce IGF-1, which mediates many of growth hormone's anabolic effects on muscle, bone, and other tissues. Clinical trials showed IGF-1 levels remained elevated above baseline for up to 28 days following multiple doses.