Growth Hormone Pulse Amplification Research
CJC-1295 without DAC (also called Modified GRF 1-29) is a chemically modified version of Sermorelin with four amino acid substitutions that dramatically increase its stability against peptidase degradation. It retains full GHRH receptor agonist activity, producing strong GH pulses when administered, while its extended plasma half-life (approximately 30 minutes vs. ~2 minutes for native GHRH) makes it a valuable research tool for GH axis studies.
CJC-1295 without DAC is a synthetic analogue of GHRH(1-29) — identical in sequence to Sermorelin at positions 1–29, but with four key amino acid substitutions: Ala⁸ → Gln, Gly¹⁵ → Ala, Gly²⁷ → Ala, and replacement of Met²⁷ with Nle to prevent oxidation. These modifications dramatically increase resistance to DPP-IV and other peptidases, extending the plasma half-life from approximately 2 minutes (native GHRH) to approximately 30 minutes for CJC-1295 no DAC.
It should not be confused with CJC-1295 with DAC (which has an additional Drug Affinity Complex that binds albumin to extend half-life to approximately 8 days). The no-DAC form produces more physiological, pulsatile GH release patterns and is the preferred form in most current research protocols.
Like Sermorelin, CJC-1295 (no DAC) binds to pituitary GHRH receptors (GHRHR), activating the cAMP/PKA pathway and triggering pulsatile GH release. The four amino acid substitutions prevent rapid degradation by DPP-IV and other peptidases, allowing a sustained receptor interaction that produces larger GH pulses than native GHRH while still maintaining physiological pulsatility.
Research demonstrates a synergistic relationship between GHRH analogues and growth hormone-releasing peptides (GHRPs). While CJC-1295 stimulates the release of GH already stored in somatotroph secretory granules, GHRPs like Ipamorelin act through a distinct mechanism (ghrelin receptor agonism) to amplify this release further. The combination of CJC-1295 + Ipamorelin is one of the most studied peptide combinations for GH axis research due to this synergistic amplification.
The GH released in response to CJC-1295 drives hepatic IGF-1 production, which mediates the anabolic, lipolytic, and tissue-repair effects associated with GH axis activation. Research in animal models demonstrates improved body composition, increased lean mass, and reduced adiposity with sustained CJC-1295 treatment.
Jetté L et al. demonstrated in a placebo-controlled study that a single subcutaneous injection of CJC-1295 produced dose-dependent increases in plasma GH (mean 2–10 fold) and IGF-1 (mean 1.5–3 fold) with the GH elevation persisting for 6 hours and IGF-1 for 9–11 days, establishing the extended pharmacodynamic profile.
Research consistently demonstrates that the combination of a GHRH analogue (CJC-1295 or Sermorelin) with a GHRP (Ipamorelin) produces GH pulses significantly greater than either agent alone, through complementary pre-synaptic (GHRH) and post-synaptic (ghrelin receptor) mechanisms at the pituitary somatotroph.
Teichman SL et al. examined extended CJC-1295 treatment in GH-deficient animal models, reporting significant improvements in lean body mass, reduction in adipose tissue, and improved bone density, with a safety profile superior to direct GH administration due to maintained physiological pulsatility.
Research on GHRH analogues including CJC-1295 analogues demonstrates correlation between GH pulse amplitude and slow-wave sleep duration. Animals treated with GHRH analogues show increased slow-wave sleep and more robust GH secretion during sleep phases, linking GH axis activity to sleep quality.
CJC-1295 (no DAC) reconstitutes readily in bacteriostatic water. A 5mg vial reconstituted in 2.5ml BAC water gives a 2 mg/ml working solution. Reconstituted peptide should be stored at 2–8°C and used within 28 days.
Most research protocols using CJC-1295 no DAC employ doses in the 100–300 mcg range per administration in human-weight equivalent models. The combination with Ipamorelin (typically 1:1 molar ratio or 100:100 mcg) is frequently studied. These figures are for scientific reference only.
| Product Name | CJC-1295 Without DAC (Modified GRF 1-29) |
| CAS Number | 863288-34-0 |
| Molecular Weight | 3,368.0 Da |
| Sequence | Modified Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Nle-Ser-Arg-NH₂ |
| Modifications | Ala⁸→Gln, Gly¹⁵→Ala, Gly²⁷→Ala, Met²⁷→Nle |
| Appearance | White lyophilized powder |
| Purity | ≥99% (HPLC) |
| Storage (lyophilized) | −20°C, protected from light |
| Storage (reconstituted) | 2–8°C, use within 28 days |
| COA | Available with each order |
