CJC-1295 is a laboratory development code, not a descriptive name. The parenthetical “DAC” is the part that carries meaning.

DAC stands for Drug Affinity Complex — a small chemical group attached to the peptide so that, once in the bloodstream, it forms a bond with circulating serum albumin. The peptide itself is an engineered version of GHRH (growth-hormone-releasing hormone), the natural signal that prompts the pituitary gland to release growth hormone. So the label describes a GHRH-type peptide fitted with an albumin-binding attachment.

It is a synthetic peptide built on the first 29 amino acids of GHRH, with four amino-acid substitutions and an added albumin-binding group.

The peptide portion is the same tetrasubstituted GHRH(1-29) used in the no-DAC form (often called Mod GRF 1-29), carrying substitutions at positions 2, 8, 15 and 27 that make it more resistant to breakdown. The distinguishing feature of this version is the maleimide-based DAC group, which reacts with albumin once injected.

It descends from native GHRH, a hypothalamic hormone whose structure was determined in 1982.

Human GHRH was isolated and sequenced in 1982 from pancreatic tumors that were causing excess growth-hormone release, work credited to teams led by Roger Guillemin and, independently, by Michael Thorner and Lawrence Frohman. The 1-29 fragment was later found to keep the hormone’s full activity. The albumin-binding Drug-Affinity-Complex technology was developed by the biotechnology company ConjuChem in the early 2000s and applied to this stabilized GHRH fragment to create the DAC version.

Native GHRH disappears from the blood within minutes, so the design goal was to keep a GHRH signal present for far longer.

Two problems were addressed. First, natural GHRH is cut apart quickly by an enzyme (DPP-IV) and is prone to chemical degradation; the four amino-acid substitutions were chosen to blunt those weaknesses. Second, even a stabilized short peptide is filtered out by the kidneys within minutes. Attaching the DAC group lets the molecule latch onto albumin — one of the most abundant and long-lived proteins in blood — so it circulates for days rather than minutes, producing a prolonged, low-level stimulus to the growth-hormone axis.

It is produced by solid-phase peptide synthesis, then chemically conjugated to its albumin-binding group.

The amino-acid chain is assembled one residue at a time on a solid resin (SPPS), cleaved, and the maleimide-based DAC group is attached to a lysine side chain. The finished material is purified by high-performance liquid chromatography (HPLC) and its identity confirmed by mass spectrometry. Because the DAC linkage must be intact and correctly placed, purity checks focus on both the peptide sequence and the conjugation.

Of the two CJC-1295 forms, this DAC version is the one with published human pharmacology data — but the overall clinical record remains thin.

An early published clinical-pharmacology study in 2006 reported that single subcutaneous doses raised mean blood growth-hormone and IGF-1 concentrations for several days, confirming the intended long-acting behavior. Beyond that early work, there are no large or long-term human trials establishing benefit or safety for the uses it is often discussed for. Sustained elevation of the growth-hormone axis carries recognized theoretical risks, and these have not been characterized for this molecule in rigorous long-term studies.

This entry is provided strictly for research and educational reference. It is not a medicine, not a supplement, and nothing here is dosing or usage guidance.