CJC-1295 DAC

CJC-1295 with DAC is a modified analogue of growth-hormone-releasing hormone, built on the GHRH(1-29) fragment — the shortest portion of the native hormone that retains full biological activity. Four amino acid substitutions protect it against enzymatic degradation, and a Drug Affinity Complex, a maleimidoproprionic acid group, allows the molecule to form a covalent bond with circulating serum albumin after administration.

That albumin conjugation is the entire point of the design. Native GHRH has a half-life measured in minutes; bound to albumin, the analogue persists for days. The preclinical pharmacology therefore reports something native GHRH cannot produce: a sustained elevation in circulating GH and, downstream, in IGF-1, maintained over a period rather than expressed as a pulse.

Animal work covers GH and IGF-1 response curves, and the compound has been used as a research tool for examining what continuous rather than pulsatile GHRH receptor stimulation does to the somatotropic axis. That question matters, because GH is physiologically secreted in pulses, and the biological consequences of pulsatile and continuous exposure are known to differ.

CJC-1295 with DAC has more human data behind it than most compounds in this catalogue, though the record is small and dated. Phase 1 studies conducted by ConjuChem and published in the Journal of Clinical Endocrinology and Metabolism reported that single doses produced sustained increases in GH and IGF-1 in healthy adults lasting several days, with dose-dependent magnitude. Those studies established the pharmacokinetic claim that defines the compound.

Development did not continue to approval. The compound has no marketing authorisation from Health Canada, the FDA or any comparable authority for any indication, and the later-stage trials that would have characterised safety over extended exposure were not completed and published.

That leaves an awkward evidentiary position: short-term human pharmacokinetics are documented, and long-term human safety is not. The absence of completed later-phase data is not neutral information — it is the part of the record that would matter most for any sustained exposure.

The claim that CJC-1295 with DAC raises GH and IGF-1 for days from a single administration is supported by published phase 1 human data. This is one of the better-evidenced pharmacokinetic claims in the research-peptide space.

The claim that this is straightforwardly desirable is where the evidence stops. Growth hormone is secreted physiologically in pulses, with troughs between them, and receptor systems generally respond differently to continuous versus intermittent stimulation. Converting a pulsatile axis into a continuously elevated one is a real pharmacological intervention with consequences that the published record does not characterise. Sustained IGF-1 elevation is not simply a stronger version of a natural state.

A third claim treats DAC and non-DAC versions as the same compound at different durations. They produce fundamentally different exposure patterns, and the literature does not support reading data from one as applicable to the other.

The comparison that matters most is with CJC-1295 without DAC, properly Modified GRF (1-29). Same GHRH-analogue backbone, radically different pharmacokinetics: minutes versus days. The non-DAC version produces a sharp pulse resembling physiological secretion; the DAC version produces a sustained plateau. Choosing between them is choosing between two different experimental questions, not two strengths of the same thing.

Against ipamorelin and GHRP-2, the difference is receptor system. CJC-1295 acts at the GHRH receptor; those act at the growth hormone secretagogue receptor, the ghrelin receptor. The two systems are complementary, which is why the literature pairs a GHRH analogue with a ghrelin-receptor agonist and reports a greater combined response than either alone.

Against tesamorelin, the compounds are closest in class — both GHRH analogues — but tesamorelin has completed clinical development and holds regulatory approval for a defined indication, which CJC-1295 does not.

The most substantive concern follows from the mechanism rather than from any reported adverse event: sustained elevation of GH and IGF-1. IGF-1 is a mitogen, and elevated IGF-1 has been associated in epidemiological work with increased risk of several cancers. Acromegaly, the pathological state of chronic GH excess, is characterised by soft tissue overgrowth, glucose intolerance, hypertension, cardiomyopathy, joint disease and increased mortality. A compound designed to hold GH and IGF-1 elevated continuously operates in the direction of that physiology, and no published study has characterised the consequences of doing so over extended periods.

More immediate documented effects of GH axis stimulation include insulin resistance and impaired glucose tolerance, fluid retention, arthralgia and carpal tunnel symptoms.

The compound is on the World Anti-Doping Agency Prohibited List under S2. Long-term human safety data does not exist, and the discontinuation of clinical development means the studies that would have produced it were never completed.

CJC-1295 with DAC ships lyophilized. The DAC modification extends serum half-life after administration; it does not make the peptide more robust in the vial, and handling should be no less careful than for any other GHRH analogue.

Introduce bacteriostatic water slowly against the vial wall rather than onto the powder cake, and swirl gently until dissolved. Do not shake — foaming denatures peptide at the air-water interface. Store reconstituted material at 2–8 °C protected from light and observe the working window given on this page. Keep unopened lyophilized vials frozen for long-term storage, and avoid repeated freeze-thaw cycling of solutions.