CJC-1295

CJC-1295 without DAC is used in GHRH receptor pharmacology, somatotroph cell studies and GH release kinetics. It is the usual GHRH-side partner in two-receptor designs with a ghrelin-receptor agonist such as ipamorelin. The human studies cited here used the DAC form, so check which molecule a paper used.

Both share the tetrasubstituted GRF (1-29) chain and act at the GHRH receptor. The DAC form adds a C-terminal lysine carrying a maleimidopropionamide group, which binds Cys34 of serum albumin. In rats that conjugate was still in plasma after 72 hours (Jetté et al., Endocrinology, 2005).

In healthy adults the DAC form had a half-life of 5.8 to 8.1 days (Teichman et al., 2006). GH secretion stayed pulsatile under that continuous stimulation, with trough levels up 7.5-fold (Ionescu and Frohman, 2006). The no-DAC form has no albumin anchor, so it suits short, pulse-like stimulation. At 3647.2 against 3367.9 g/mol, mass spectrometry tells the two apart.

CJC-1295 (no DAC) is a synthetic analogue of growth hormone releasing hormone (GHRH), also referred to as modified GRF 1-29. It binds to GHRH receptors in the anterior pituitary gland to stimulate the synthesis and secretion of growth hormone. The no DAC (Drug Affinity Complex) version lacks the maleimidopropionic acid linker present in CJC-1295 with DAC, resulting in a shorter half-life that produces more pulsatile GH release patterns. Researchers consider this pulsatile pattern more physiologically similar to natural endogenous GH secretion, making CJC-1295 no DAC particularly valuable for studies requiring physiological GH release kinetics. The compound is frequently studied in combination with Ipamorelin, a selective GHS-R1a agonist, for synergistic effects through complementary receptor pathways, CJC-1295 stimulating GH release via the GHRH receptor while Ipamorelin acts at the ghrelin receptor. This dual-pathway approach produces amplified GH pulses and has become a standard research protocol in growth hormone biology. Studies have examined CJC-1295's effects on plasma GH levels, IGF-1 production, body composition, and sleep-related GH secretion patterns.

The naming around this compound is genuinely confused across the research-chemical market and is worth untangling, because it affects which papers actually apply. CJC-1295 as originally developed by ConjuChem was the DAC-bearing molecule, the drug affinity complex being the defining feature of the compound that carried that code. What is universally sold as “CJC-1295 without DAC” is more accurately tetrasubstituted GRF(1-29), a GHRH fragment carrying D-Ala at position 2, Gln at 8, Ala at 15 and Leu at 27. The substitution that does the real work is D-Ala2, which blocks cleavage by dipeptidyl peptidase-4, the protease that degrades native GHRH within minutes.

The practical consequence is that a good deal of literature cited for “CJC-1295 no DAC” is in fact about the DAC molecule, about mod GRF(1-29), or about native GHRH. Teichman and colleagues (J Clin Endocrinol Metab, 2006), the most frequently cited clinical work, studied the DAC-bearing version, whose sustained albumin-bound profile is not the pulsatile profile this vial produces. Researchers reading around the compound should check which molecule a given paper actually used.

Neither version holds a marketing authorisation in any jurisdiction; ConjuChem's clinical programme did not reach approval.