CJC-1295

What it is

The 'No DAC' designation refers to the absence of the Drug Affinity Complex — a lysine modification that, when present, covalently binds to albumin in the bloodstream and extends the peptide's half-life to 6–8 days. Without DAC, CJC-1295 has an active window of approximately 30 minutes, which more closely mimics the natural pulsatile pattern of endogenous GHRH secretion. This makes the No DAC version the preferred choice in research investigating physiological GH pulse dynamics, rather than sustained GH elevation. CJC-1295 No DAC is a 29-amino acid peptide (a modified fragment of endogenous GHRH) with four amino acid substitutions at positions 2, 8, 15, and 27 that confer greater enzymatic stability than native GHRH.

How it works

CJC-1295 No DAC binds to the GHRH receptor (GHRHR) on somatotroph cells of the anterior pituitary, stimulating the synthesis and release of growth hormone in a pulse. The amplitude and duration of the resulting GH pulse is greater than that produced by native GHRH, due to the enhanced receptor affinity conferred by its amino acid substitutions. When studied in combination with a GHRP such as Ipamorelin, CJC-1295 No DAC acts synergistically — the two peptides operate on separate receptor systems (GHRHR and GHS-R1a respectively), producing amplification of GH pulse magnitude beyond what either compound achieves alone. This dual-receptor approach is the basis for its widespread use as a research pairing.

Research context

Research has investigated GHRH analogues in contexts including body composition, bone mineral density, sleep architecture (particularly slow-wave sleep), immune function, and metabolic regulation. CJC-1295 No DAC is preferred over the DAC variant in research where pulsatile, physiological-pattern GH release is the objective, rather than sustained supraphysiological elevation. The Modified GRF 1-29 sequence has a well-documented pharmacological profile across multiple published studies in endocrinology journals.