Educational reference, not medical advice. This page summarizes information from published research and regulatory filings for educational purposes. It is not a recommendation to use any compound and should not replace guidance from a licensed healthcare provider. Most peptides discussed here are not approved for the uses described.
What it is
CJC-1295 DAC is a long-acting analog of growth hormone-releasing hormone (GHRH). The "DAC" — Drug Affinity Complex — is a maleimide group attached to the C-terminus that forms a covalent bond with cysteine-34 on circulating albumin. Once bound to albumin, the peptide is shielded from rapid enzymatic clearance, extending the half-life from minutes to several days. It is structurally similar to CJC-1295 (no DAC) and sermorelin but pharmacokinetically very different from both.
History
ConjuChem, a Montreal biotechnology company, developed the DAC technology in the early 2000s as a general platform for extending peptide drug half-lives. The 2006 paper by Teichman and colleagues in the Journal of Clinical Endocrinology & Metabolism reported the first human pharmacokinetic data: single subcutaneous doses produced 2- to 10-fold elevations in mean plasma GH for six days or more, with IGF-1 elevation persisting up to 28 days.
ConjuChem advanced CJC-1295 DAC into Phase II development. Trials were halted in 2008 after a Phase II study reported a death attributed to the study drug in a patient and additional concerns over asymptomatic hypotension and dose-related cardiovascular signals. Development was discontinued and the molecule has not been advanced by any subsequent sponsor.
Regulatory status
CJC-1295 DAC has no approved medical use in any major jurisdiction. It is not on the FDA's 503A bulk substances list, and compounding pharmacies in the United States are not permitted to prepare it for patients. Like other GHRH analogs and growth hormone secretagogues, it is banned by the World Anti-Doping Agency under class S2 (peptide hormones, growth factors, related substances, and mimetics) — prohibited in and out of competition.
In the European Union and most other jurisdictions, CJC-1295 DAC is unscheduled but unauthorized for therapeutic use. Supply is routed through research-chemical channels with not-for-human-use labeling.
Mechanism
The published mechanism papers describe CJC-1295 DAC as a GHRH receptor agonist that, by virtue of its albumin binding, maintains continuous receptor occupancy for days at a time. This produces a sustained elevation of GH and IGF-1 rather than the pulsatile pattern that characterizes the body's own GHRH and the short-acting analogs (sermorelin, Mod GRF 1-29).
Ionescu and Frohman (2006) demonstrated that some pulsatility is preserved even during continuous stimulation, because somatostatin — the counter-regulatory hormone — continues to oscillate and gates GH release. However, the baseline elevation is substantial and prolonged, which is the property that prompted clinical interest and also the safety concern that ultimately halted development.
Half-life and dosing intervals
The published terminal half-life of CJC-1295 DAC is approximately 6 to 8 days. After a single subcutaneous injection, plasma GH remains elevated for around six days, and IGF-1 elevation persists up to four weeks. With repeated weekly dosing, IGF-1 accumulates over the first several weeks before reaching steady state.
In the Phase I and II programs reported by Teichman and colleagues, doses ranged from 30 to 250 mcg/kg administered as single subcutaneous injections or as weekly doses across 28- to 49-day studies. The 30 and 60 mcg/kg doses were described as best tolerated. There is no established or approved human dose.
Reconstitution example
CJC-1295 DAC is sold lyophilized in 2 mg or 5 mg vials. A 2 mg vial reconstituted with 2 mL of bacteriostatic water yields 1 mg/mL — on a 1 mL U-100 insulin syringe, 10 units (0.1 mL) contains 1 mg.
A 5 mg vial reconstituted with 2.5 mL of bacteriostatic water yields 2 mg/mL — 10 units then contains 2 mg. Vial's calculator handles the unit-to-mg conversion automatically.
What to know
- Discontinued in development. ConjuChem halted Phase II development in 2008 after safety signals including asymptomatic hypotension; the molecule has not been advanced since.
- Not approved. No regulator has authorized CJC-1295 DAC for therapeutic use, and compounding pharmacies in the United States cannot prepare it for patients.
- WADA banned. Use is prohibited in competitive sport.
- Sustained GH elevation. Unlike short-acting GHRH analogs, the DAC variant produces continuous (rather than pulsatile) GH and IGF-1 elevation, which is the basis of both its appeal and its safety concerns.
- Reported side effects in published trials and observational use include injection-site flushing, transient drops in blood pressure, headaches, paresthesias, and water retention. Long-term safety has not been characterized.
- Storage. Lyophilized vials are best stored refrigerated. Once reconstituted, refrigerate and use within 4 weeks per typical supplier stability data.
- Distinction from CJC-1295 (no DAC). Despite the shared name, the two molecules are pharmacokinetically very different — the DAC version has a half-life of days, the non-DAC version of under an hour.
Sources
- 1.Teichman SL et al. (2006). Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. Journal of Clinical Endocrinology & Metabolism.
- 2.Ionescu M, Frohman LA (2006). Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. Journal of Clinical Endocrinology & Metabolism.
- 3.Sigalos JT, Pastuszak AW (2018). The Safety and Efficacy of Growth Hormone Secretagogues. Sexual Medicine Reviews.
- 4.World Anti-Doping Agency — Prohibited List (S2).