Modified GRF 1-29 · GHRH Analogue · DAC and No-DAC forms
A synthetic 30-amino acid analogue of growth hormone-releasing hormone (GHRH). Universally stacked with Ipamorelin to produce synergistic GH pulses through dual receptor activation. Exists in two fundamentally different forms, DAC and no-DAC, that require entirely different protocols.
01, Research Summary
CJC-1295 was developed by ConjuChem Biotechnologies as a longer-acting GHRH analogue. The published clinical dataset consists of two Phase 1 RCTs from 2006, establishing that CJC-1295 with DAC produces sustained GH and IGF-1 elevation for up to 13 days following a single injection in healthy adults. No Phase 2 or Phase 3 trials are registered as of 2026.
Sustained GH and IGF-1 elevation confirmed. CJC-1295 with DAC produced 2–6 fold increases in mean GH concentration and 1.5–3 fold IGF-1 increases sustained for 6–13 days following a single subcutaneous injection in 65 healthy adults.
Pulsatile GH secretion maintained during sustained GHRH stimulation. Despite continuous receptor activation, the pituitary maintained natural pulsatile GH secretion, enhanced trough levels drive IGF-1 without eliminating physiological feedback.
The no-DAC form (Mod GRF 1-29) has no dedicated clinical trials, its use is extrapolated from the DAC form's mechanism and from sermorelin research on the same GHRH receptor pathway. The pharmacology is well-characterised; the human outcome data is limited.
02, Mechanism of Action
CJC-1295 binds the pituitary GHRH receptor, activating adenylate cyclase and increasing intracellular cAMP, triggering GH synthesis and release. The compound is engineered to resist enzymatic degradation that rapidly breaks down native GHRH.
CJC-1295 binds the pituitary GHRH receptor with high affinity, activating adenylate cyclase and increasing intracellular cAMP, the same initial pathway as endogenous GHRH but with dramatically extended duration due to DPP-IV resistance.
Elevated cAMP drives GH gene transcription and calcium influx, triggering exocytosis of stored GH in pulses. Critically, the pituitary maintains its natural somatostatin feedback brake, providing a safety mechanism absent in exogenous GH administration.
When combined with ipamorelin (ghrelin receptor agonist), dual receptor activation on the same pituitary somatotroph cell produces synergistic GH pulses significantly larger than either compound alone, the mechanistic basis for the most popular GH peptide stack.
CJC-1295 with DAC binds albumin after injection (6–8 day half-life, once-weekly 1–2mg). CJC-1295 without DAC has ~30-minute half-life (daily 100–200 mcg). These are not interchangeable. Applying daily-dose amounts to the DAC version risks sustained supra-physiological GH. Always confirm which form you have.
03, Dosing Context
Protocol depends entirely on which form is being used.
| Form | Dose | Frequency | Timing |
|---|---|---|---|
| No DAC (Mod GRF 1-29) | 100–200 mcg | Daily or 2–3x/day | Fasted, before bed primary |
| With DAC | 1–2 mg | Once weekly | Any time, consistent day |
For the no-DAC + ipamorelin stack, before-bed administration amplifies the natural nocturnal GH surge. Empty stomach is essential, insulin elevation suppresses GH release. Standard cycling: 8 weeks on, 8 weeks off to prevent receptor downregulation.
CJC-1295 with DAC at daily-dose amounts can cause sustained supra-physiological GH elevation. Confirm which form you have before dosing. The two products require completely different protocols.
04, Community
Community reports for CJC-1295 almost exclusively describe it as part of the ipamorelin stack. The combination is the most discussed GH peptide protocol in research communities. Consistently reported early effects are improved sleep quality within 1–2 weeks, enhanced recovery, and modest body composition changes over 8–12 week cycles. Skin quality and recovery speed are also commonly reported.