CJC-1295 exists because of a chemistry problem. Native growth-hormone-releasing hormone survives in the bloodstream for only a few minutes before enzymes tear it apart. For decades that made it almost useless as a research tool for studying sustained growth hormone signaling. CJC-1295 was the attempt to fix that half-life problem at the molecular level, and its story runs from a 1982 hormone discovery to a small Canadian biotech firm’s patented linker chemistry.
The GHRH lineage behind CJC-1295
The starting point is growth-hormone-releasing hormone, or GHRH. It was isolated in 1982 by two research groups working on pancreatic tumors that were driving abnormal growth hormone output, work associated with Roger Guillemin’s laboratory and with Wylie Vale and colleagues. GHRH is the signal the hypothalamus sends to the pituitary to prompt growth hormone release.
Researchers quickly found that the full 44-amino-acid hormone was not needed. The first 29 amino acids, the fragment called GRF(1-29), carried essentially all of the biological activity. That fragment became known as sermorelin, and a version of it was developed as a pharmaceutical (marketed as Geref) and used in growth hormone testing and pediatric research. Sermorelin is the closest synthetic approximation to the natural hormone, but it inherits the same weakness: a half-life reported at roughly 11 to 12 minutes. Every peptide in this family, CJC-1295 included, traces back to that 1-29 fragment.
Who made CJC-1295
CJC-1295 was developed by ConjuChem Biotechnologies, a company based in Montreal, Quebec, Canada, in the early-to-mid 2000s. ConjuChem’s specialty was not the peptide itself but a delivery concept it called the Drug Affinity Complex, or DAC. The idea was to take short-lived peptides and give them a way to hitchhike on something that already lasts a long time in the body.
The team started with the GRF(1-29) backbone and made four amino acid substitutions, at positions 2, 8, 15, and 27. Those swaps were not about changing what the peptide does; they were about survival, making the molecule resistant to the enzymes that normally chew through GHRH. This tetrasubstituted, protease-resistant version is the structural core of everything sold today under the CJC-1295 name.
The second half of ConjuChem’s engineering was the DAC itself: a maleimide-based chemical group attached through a lysine linker. Human serum albumin, the most abundant protein in blood plasma, carries a single reactive thiol at cysteine-34. Maleimide chemistry is selective for exactly that kind of free thiol, so once injected, the peptide forms a stable covalent bond to circulating albumin. Albumin has a plasma half-life of roughly 19 days, and the attached peptide inherits much of that longevity, protected from rapid filtration and breakdown.
CJC-1295 DAC vs no DAC
This is where most of the confusion around the compound comes from, so it is worth being precise. There are two distinct molecules, and the difference is the DAC.
The with-DAC version is the original CJC-1295 as ConjuChem described it: the modified GRF(1-29) backbone plus the albumin-binding complex. Because it latches onto albumin, its reported half-life stretches to somewhere around 6 to 8 days, with published figures in the 5.8 to 8.1 day range. That is a more than fortyfold extension over the unmodified fragment.
The no-DAC version is just the four-substitution backbone with no albumin-binding group attached. Its technically correct name is modified GRF(1-29), often shortened to mod GRF 1-29, though the market frequently and misleadingly labels it “CJC-1295 without DAC.” Its reported half-life is only about 30 minutes. In research terms the two behave very differently: the no-DAC form produces a brief, pulse-like signaling profile closer to sermorelin, while the DAC form produces a sustained, prolonged elevation. Same peptide family, same backbone, radically different duration, one small piece of linker chemistry apart.
What the research showed, and where it stopped
The most-cited human data comes from a Phase 1 study published in 2006 by Teichman and colleagues in The Journal of Clinical Endocrinology & Metabolism (volume 91, issue 3, pages 799 to 805). In healthy adults, single subcutaneous administrations of CJC-1295 were reported to raise mean plasma growth hormone and IGF-I concentrations for a period of days, confirming that the albumin-binding strategy produced the intended long-acting effect. No serious adverse reactions were reported at the tested doses in that early trial.
ConjuChem carried the compound into Phase 2 development, including a trial in HIV-associated lipodystrophy around 2006. That program did not advance to approval, and clinical development of CJC-1295 was discontinued. It has never been an approved medicine anywhere. This matters for anyone reading about it today: the published human evidence is thin, limited to early-stage trials from nearly two decades ago, and the compound’s long-term profile in people was never established. It remains an experimental molecule, not a validated therapy, and most of what circulates online about it extrapolates well beyond that small evidence base.
→ CJC-1295 & Ipamorelin Research Guide · COA available CJC-1295 range
Research use only. CJC-1295 is supplied by Vero Labs strictly as a research compound for laboratory investigation. It is not intended for human or animal use, and nothing here is medical advice or a suggestion of any application. Every batch we supply is independently third-party lab-tested for identity and purity, with a published Certificate of Analysis (COA).