CJC-1295: A Growth Hormone-Releasing Hormone Analog — Research Overview
CJC-1295: A Growth Hormone-Releasing Hormone Analog — Research Overview
CJC-1295 is a synthetic 30-amino acid peptide analog of growth hormone-releasing hormone (GHRH, also known as somatoliberin). It was developed by ConjuChem Biotechnologies through modification of the first 29 amino acids of human GHRH (1-29), with four amino acid substitutions at positions 2, 8, 15, and 27 designed to increase receptor binding affinity and resist enzymatic degradation by dipeptidyl peptidase-IV (DPP-IV). CJC-1295 exists in two primary research forms: CJC-1295 without DAC (also called Modified GRF 1-29 or Mod GRF) and CJC-1295 with DAC (Drug Affinity Complex), which includes a maleimidopropionic acid linker enabling covalent binding to serum albumin for extended half-life.
Mechanism of Action
CJC-1295 acts as an agonist at the growth hormone-releasing hormone receptor (GHRHR), a G protein-coupled receptor expressed primarily on somatotroph cells of the anterior pituitary gland. Upon binding, it stimulates the synthesis and secretion of growth hormone (GH) through a cAMP-dependent signaling cascade.
The key pharmacological distinction of CJC-1295 from native GHRH relates to its resistance to DPP-IV cleavage. Native GHRH(1-44) has a plasma half-life of approximately 7 minutes due to rapid N-terminal cleavage by DPP-IV. The amino acid substitutions in CJC-1295 protect against this degradation, extending the peptide's duration of action (Jetté et al., Endocrinology, 2005; PMID: 15845616).
Without DAC: CJC-1295 without DAC (Mod GRF 1-29) has a half-life estimated at approximately 30 minutes. It produces a pulse-like GH release pattern that more closely mimics physiological GH secretion, with peak GH levels occurring within 30–60 minutes of administration in preclinical models.
With DAC: The Drug Affinity Complex modification enables CJC-1295 to covalently bind to circulating albumin, extending its effective half-life to approximately 6–8 days. This produces a sustained elevation of GH and IGF-1 levels rather than discrete pulses (Teichman et al., Journal of Clinical Endocrinology & Metabolism, 2006; PMID: 16368745).
An important distinction from direct GH administration: CJC-1295 stimulates endogenous GH production through the natural GHRH pathway, preserving the pulsatile release pattern and negative feedback mechanisms governed by somatostatin.
Published Research
Pharmacokinetics and GH response: In a Phase I/II clinical study, Teichman et al. demonstrated that a single subcutaneous dose of CJC-1295 with DAC produced dose-dependent increases in plasma GH and IGF-1 levels that remained elevated for 6–14 days in healthy subjects. Mean IGF-1 levels increased by 1.5 to 3-fold above baseline (Teichman et al., JCEM, 2006; PMID: 16368745).
Pulsatile vs. sustained release: Research comparing the two forms has examined the physiological implications of pulsatile (without DAC) versus sustained (with DAC) GH stimulation. Pulsatile GH secretion is considered more physiological, as natural GH release occurs in discrete bursts predominantly during sleep, while continuous elevation may alter the GH/IGF-1 axis feedback dynamics.
Synergy with GHRP compounds: CJC-1295 without DAC is frequently studied in combination with growth hormone-releasing peptides (GHRPs) such as Ipamorelin, which act through the ghrelin/GHS receptor rather than the GHRH receptor. In preclinical models, co-administration has been observed to produce synergistic GH release — the combined response exceeding the sum of individual responses — as the two pathways converge on the somatotroph through distinct intracellular signaling cascades.
Body composition studies: In animal models, sustained GH elevation via GHRH analogs has been associated with changes in body composition metrics, including alterations in lean mass and adipose tissue distribution, consistent with known GH/IGF-1 axis effects on metabolism.
Purity and Quality Considerations
CJC-1295 is a 30-amino acid peptide, and researchers should be aware of the distinction between the "with DAC" and "without DAC" forms when sourcing. These are chemically distinct compounds with different pharmacokinetic profiles. Verify the specific form, purity (≥98% by HPLC), and molecular weight via mass spectrometry. Learn more about peptide purity testing and Certificate of Analysis standards.
Available for Research
CALM Peptides offers research-grade CJC-1295 in both forms: CJC-1295 without DAC and CJC-1295 with DAC. A convenient 2X Blend (CJC-1295/Ipamorelin) is also available. Certificates of Analysis are available upon request. Browse all strength peptides or explore our full catalog.
Frequently Asked Questions
What is CJC-1295?
CJC-1295 is a synthetic 30-amino acid analog of growth hormone-releasing hormone (GHRH) studied for its effects on growth hormone secretion. It is available in two forms: without DAC (shorter-acting, pulsatile) and with DAC (longer-acting, sustained release).
What is the difference between CJC-1295 with and without DAC?
CJC-1295 without DAC (Mod GRF 1-29) has an estimated half-life of ~30 minutes and produces pulse-like GH release. CJC-1295 with DAC includes a Drug Affinity Complex that binds to albumin, extending its effective half-life to approximately 6–8 days with sustained GH elevation.
Why is CJC-1295 often studied alongside Ipamorelin?
CJC-1295 acts through the GHRH receptor while Ipamorelin acts through the ghrelin/GHS receptor. In preclinical models, co-administration through these complementary pathways has been observed to produce synergistic growth hormone release.
How does CJC-1295 differ from direct growth hormone administration?
CJC-1295 stimulates endogenous GH production via the GHRH receptor on pituitary somatotrophs, preserving the body's natural pulsatile release pattern and negative feedback mechanisms. Direct GH administration bypasses these regulatory pathways.
The information presented in this article is for educational and informational purposes only and is not intended as medical advice. CJC-1295 is sold as a research chemical for laboratory use only. It is not intended for human consumption, and should not be used to diagnose, treat, cure, or prevent any disease. All references to published research are provided for informational context. Consult qualified professionals for guidance related to any health condition.
For research use only. Not for human consumption.
Related Reading: What Are Peptides? · Strength & Performance Peptides · Ipamorelin Research Overview · Quality & Purity Standards · Peptide Purity Testing
The information presented in this article is for educational and informational purposes only and is not intended as medical advice. All products referenced are sold as research chemicals for laboratory use only. They are not intended for human consumption and should not be used to diagnose, treat, cure, or prevent any disease. All references to published research are provided for informational context. Consult qualified professionals for guidance related to any health condition.