CJC-1295 no DAC

CJC-1295 no DAC is a synthetic analogue of growth hormone-releasing hormone (GHRH) engineered to stimulate the pituitary growth hormone-releasing hormone receptor (GHRHR) while exhibiting greater metabolic stability than native GHRH. Derived from the biologically active 29-amino-acid region of human GHRH, the peptide incorporates four targeted amino acid substitutions that improve resistance to enzymatic degradation while preserving receptor affinity and physiological receptor signalling.

Unlike recombinant human growth hormone (rHGH), CJC-1295 no DAC stimulates endogenous growth hormone secretion by activating the GHRH receptor upstream within the hypothalamic-pituitary axis. Its relatively short duration of action allows researchers to investigate regulation of the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis, endocrine feedback mechanisms, receptor pharmacology, and physiological pulsatile growth hormone secretion under conditions that more closely resemble native GHRH signalling than long-acting GHRH analogues.

Researchers within the European Union can buy CJC-1295 no DAC 10mg from Crystal Peptides as high-purity research compounds independently tested by accredited laboratories, and every product batch accompanied by a Certificate of Analysis to verify identity, purity, and analytical quality.

CJC-1295 no DAC vs CJC-1295 with DAC vs Modified GRF (1-29)

Although CJC-1295 no DAC and CJC-1295 with DAC share the same modified GHRH backbone and activate the same receptor, they differ fundamentally in their pharmacokinetic behaviour. CJC-1295 with DAC incorporates a Drug Affinity Complex that forms a stable covalent bond with circulating serum albumin, extending its half-life from approximately 30 minutes to around one week.

CJC-1295 no DAC lacks this albumin-binding modification, making it the preferred research tool when transient receptor activation and physiological endocrine signalling are the focus of investigation.

On the other hand, Modified GRF (1-29) is the scientific name for the peptide commonly marketed as CJC-1295 without DAC or CJC-1295 no DAC. All three names refer to the same four-substitution GHRH analogue. The alternative market terminology was adopted simply to distinguish the peptide from CJC-1295 with DAC, which incorporates the additional Drug Affinity Complex and therefore exhibits substantially different pharmacokinetic properties.

Chemical properties and registry information

CJC-1295 no DAC Clinical data

Unlike CJC-1295 with DAC, CJC-1295 without DAC has not been the subject of a dedicated clinical development programme. The main published studies involve long-acting GHRH analogues evaluating the albumin-binding DAC formulation.

Modified GRF (1-29) has been characterised primarily through peptide engineering, receptor pharmacology, and laboratory research. Nevertheless, the two compounds share the same modified GHRH peptide backbone and therefore the same fundamental mechanism of receptor activation.

Observations from the DAC analogue provide important insight into the pharmacology of the modified peptide itself, while the absence of the Drug Affinity Complex means that CJC-1295 without DAC produces substantially shorter receptor activation and a markedly different pharmacokinetic profile.

Accordingly, the observations discussed here are intended solely to describe the compound's pharmacological properties and should not be construed as supporting any clinical application. CJC-1295 no DAC is supplied strictly for research purposes only.

Development of Modified GRF (1-29)

CJC-1295 no DAC was engineered from the biologically active 29-amino-acid fragment of human GHRH by introducing four amino acid substitutions that improve resistance to enzymatic degradation while preserving affinity for the growth hormone-releasing hormone receptor (GHRHR). Unlike native GHRH, which is rapidly inactivated by enzymes such as dipeptidyl peptidase IV (DPP-IV), Modified GRF (1-29) exhibits improved metabolic stability while maintaining the short-duration receptor activation required for physiological studies of pulsatile growth hormone secretion. [1]

Relationship to CJC-1295 with DAC

The four amino acid substitutions found in Modified GRF (1-29) also form the peptide backbone of CJC-1295 with DAC. Clinical studies of the DAC analogue demonstrated that these substitutions preserve endogenous growth hormone pulsatility while increasing circulating growth hormone and insulin-like growth factor-1 (IGF-1) concentrations. [1]

The principal pharmacokinetic difference between the two molecules is the addition of the Drug Affinity Complex, which extends the half-life of the DAC analogue from minutes to approximately one week through albumin binding. Without this modification, CJC-1295 without DAC remains a short-acting GHRH analogue designed for transient receptor activation rather than prolonged endocrine stimulation.

Despite that, both compounds act through the same well-characterised GHRH receptor as endogenous GHRH, and its pharmacology is understood from decades of research into hypothalamic growth hormone regulation, peptide engineering, and GHRH receptor signalling.

Contemporary reviews continue to use Modified GRF (1-29) as an example of how targeted amino acid substitutions can improve peptide stability without fundamentally altering physiological receptor function.

No formulation of CJC-1295 has been authorised as a medicinal product by the European Medicines Agency (EMA), the U.S. Food and Drug Administration (FDA), or any other major medicines regulator. Our current understanding of the compound is derived from published pharmacology, peptide chemistry, and endocrine research, not authorised therapeutic use.

CJC-1295 No DAC research applications

CJC-1295 without DAC is mainly used as a research tool for investigating short-term activation of the growth hormone-releasing hormone receptor (GHRHR) and the physiological regulation of the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis. Unlike long-acting GHRH analogues, its relatively short half-life allows researchers to study transient endocrine responses that more closely resemble the natural pulsatile release of hypothalamic GHRH.

Pulsatile growth hormone physiology

The primary research application of CJC-1295 without DAC is the investigation of physiological growth hormone pulsatility. Because the peptide is cleared quickly after receptor activation, it provides a useful model for examining the timing, amplitude, and frequency of endogenous growth hormone secretion without prolonged receptor occupancy. This makes it particularly valuable in studies of hypothalamic-pituitary regulation and endocrine feedback. [1]

Growth hormone-releasing hormone receptor pharmacology

Modified GRF (1-29) is widely used to investigate the pharmacology of the GHRH receptor and the intracellular signalling pathways that regulate growth hormone synthesis and secretion. By retaining the receptor-binding characteristics of native GHRH while improving metabolic stability, the peptide enables researchers to evaluate receptor activation, ligand-receptor interactions, and downstream signalling under controlled experimental conditions. [2]

Comparative studies of GHRH analogues

CJC-1295 without DAC is frequently evaluated alongside native GHRH, Sermorelin, and CJC-1295 with DAC to investigate how structural modifications influence peptide stability, receptor activation, and pharmacokinetic behaviour. These comparative studies have contributed to a broader understanding of how peptide engineering can improve metabolic stability without fundamentally altering receptor pharmacology.

Combination signalling with growth hormone secretagogues

Because the GHRH receptor and growth hormone secretagogue receptor (GHSR-1a) regulate growth hormone secretion through complementary signalling pathways, CJC-1295 without DAC is often studied alongside ghrelin receptor agonists such as Ipamorelin. Experimental models use these compounds to investigate receptor cross-talk, endocrine regulation, and the coordinated control of endogenous growth hormone release.

Peptide engineering and metabolic stability

The four amino acid substitutions in Modified GRF (1-29) have become a widely referenced example of rational peptide engineering. Researchers continue to study how targeted structural modifications improve resistance to enzymatic degradation while preserving receptor affinity, providing insight into strategies for extending peptide stability without employing albumin-binding technologies or other long-acting delivery systems.

How CJC-1295 without DAC works (mechanism of action)

CJC-1295 without DAC is an agonist of the growth hormone-releasing hormone receptor (GHRHR), a Class B G protein-coupled receptor expressed primarily on somatotroph cells of the anterior pituitary. By binding to this receptor, the peptide stimulates endogenous growth hormone secretion through the same physiological pathway as native GHRH while exhibiting greater resistance to enzymatic degradation due to four targeted amino acid substitutions. Unlike CJC-1295 with DAC, it does not incorporate an albumin-binding modification and therefore produces transient rather than prolonged receptor activation.

Target engagement

Under physiological conditions, hypothalamic GHRH binds to the GHRH receptor on pituitary somatotrophs, initiating the synthesis and secretion of growth hormone. Native GHRH is rapidly degraded by circulating proteases, particularly dipeptidyl peptidase IV (DPP-IV), limiting its biological activity to only a few minutes.

CJC-1295 without DAC retains the receptor-binding characteristics of native GHRH while having the four amino acid substitutions: D-Ala², Gln⁸, Ala¹⁵, and Leu²⁷, which improves resistance to enzymatic degradation without altering receptor specificity.

Also, the four amino acid substitutions in Modified GRF (1-29) are an important example of rational peptide engineering, demonstrating how targeted structural changes can extend biological activity without fundamentally altering physiological receptor function.

Downstream signalling pathways

Activation of the GHRH receptor primarily stimulates the Gs signalling pathway, activating adenylate cyclase and increasing intracellular cyclic AMP (cAMP). Elevated cAMP activates protein kinase A (PKA), leading to phosphorylation of transcription factors such as CREB and promoting growth hormone synthesis and secretion. Calcium-dependent signalling pathways also contribute to hormone release, coordinating the exocytosis of stored growth hormone from pituitary somatotrophs. [3]

Endocrine effects

Growth hormone released in response to CJC-1295 without DAC acts on multiple peripheral tissues, particularly the liver, where it stimulates production of insulin-like growth factor-1 (IGF-1). Because the peptide stimulates endogenous hormone release rather than supplying growth hormone directly, normal endocrine feedback involving somatostatin, GHRH, and circulating IGF-1 remains intact. This makes the compound a valuable research tool for studying physiological regulation of the somatotropic axis.

Transient receptor activation

The defining pharmacokinetic characteristic of CJC-1295 without DAC is its relatively short duration of action. Although the four amino acid substitutions improve metabolic stability compared with native GHRH, the peptide remains a short-acting analogue because it lacks the Drug Affinity Complex responsible for albumin binding.

The resulting transient receptor activation more closely resembles endogenous hypothalamic GHRH signalling and allows researchers to investigate growth hormone secretion under conditions that preserve normal endocrine timing.

CJC-1295 no DAC vs CJC-1295 with DAC vs Ipamorelin vs Sermorelin Comparison

CJC-1295 without DAC is mainly grouped with other growth hormone-related peptides, although these compounds differ substantially in both their receptor targets and pharmacokinetic profiles.

Quality and testing

Crystal Peptides is committed to maintaining the highest standards of peptide quality and purity. Every batch undergoes HPLC purity analysis and independent third-party testing by accredited laboratories, including Janoshik Analytical. Testing extends beyond chromatographic purity to include peptide content, sterility, endotoxin, and heavy metal screening, providing researchers with a comprehensive assessment of product quality.

Each product is supplied with a batch-specific Certificate of Analysis that can be traced directly to the testing laboratory and the exact batch analysed. This enables researchers to independently verify product identity, purity, and suitability for laboratory research using transparent, traceable analytical data.

As a short-acting GHRH analogue, CJC-1295 without DAC requires confirmation of both purity and molecular identity. While HPLC verifies chromatographic purity, complementary techniques such as LC-MS confirm that the material is the correct peptide and distinguish Modified GRF (1-29) from structurally related GHRH analogues, including CJC-1295 with DAC. Together, these analytical methods provide greater confidence in the identity and integrity of the research material.

Proper handling and storage are equally important for preserving peptide stability. CJC-1295 without DAC is supplied as a lyophilised powder and should be stored sealed, dry, and protected from light, preferably at -20°C or below until required for research. Following reconstitution with bacteriostatic or sterile water, the solution should be refrigerated at 2–8°C, protected from contamination, and used within the laboratory's established stability protocols.

Practices such as repeated freeze-thaw cycles, prolonged exposure to elevated temperatures, and vigorous agitation should all be avoided, as each may accelerate peptide degradation and compromise sample integrity.

Regulatory and legal

All products supplied by Crystal Peptides are intended strictly for research and development purposes. These materials are supplied exclusively as laboratory reagents for scientific investigation and are not authorised for use in humans or animals.

This product is not a medicinal product, food, food supplement, medical device, or cosmetic. CJC-1295 without DAC has not been authorised as a medicinal product by the European Medicines Agency (EMA), the U.S. Food and Drug Administration (FDA), or any other national medicines regulator. Although the peptide has been widely characterised in peptide engineering, receptor pharmacology, and endocrine research, it has not completed the clinical development required for marketing authorisation.

Any statements regarding the compound are derived from published scientific literature and have not been evaluated by any regulatory authority. These materials are not intended to diagnose, treat, cure, or prevent any disease.

Materials must be handled only by appropriately qualified professionals trained in laboratory research procedures. Introduction of this product into humans or animals is prohibited and may breach applicable laws and regulations. Purchasers are responsible for ensuring that all acquisition, importation, storage, handling, use, and disposal complies with the legislation applicable in their jurisdiction. National requirements governing research chemicals differ between countries.

LABORATORY REAGENT, FOR RESEARCH PURPOSES ONLY. Not a medicinal product or food. Not for human consumption.

Sources and references

• Lumpkin MD, Mulroney SE, Haramati A. Inhibition of pulsatile growth hormone (GH) secretion and somatic growth in immature rats with a synthetic GH-releasing factor antagonist. Endocrinology. 1989;124(3):1154-1159.
• Jetté L, Léger R, Thibaudeau K, et al. Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analog. Endocrinology. 2005;146(7):3052-3058.
• Halmos G, Szabo Z, Dobos N, et al. Growth hormone-releasing hormone receptor (GHRH-R) and its signaling. Reviews in Endocrine and Metabolic Disorders. 2025;26(3):343-352.
• Sackmann-Sala L, Ding J, Frohman LA, et al. Activation of the GH/IGF-1 axis by CJC-1295, a long-acting GHRH analog, results in serum protein profile changes in normal adult subjects. Growth Hormone & IGF Research. 2009;19(6):471-477.

Frequently Asked Questions

What is CJC-1295 without DAC?

CJC-1295 without DAC is a short-acting synthetic analogue of growth hormone-releasing hormone (GHRH), also known as Modified GRF (1-29). It stimulates the growth hormone-releasing hormone receptor (GHRHR) in the anterior pituitary, promoting endogenous growth hormone secretion while preserving normal physiological endocrine feedback. Unlike CJC-1295 with DAC, it does not incorporate a Drug Affinity Complex and therefore produces transient receptor activation with a circulating half-life of approximately 30 minutes.

What is the difference between CJC-1295 without DAC and CJC-1295 with DAC?

The principal difference is the presence of the Drug Affinity Complex (DAC). Modified GRF (1-29), which is commonly marketed as CJC-1295 without DAC or CJC-1295 no DAC, contains the same modified GHRH peptide backbone but lacks the albumin-binding DAC modification. Consequently, CJC-1295 without DAC remains a short-acting peptide, whereas CJC-1295 with DAC remains in circulation for approximately one week. Although both activate the same receptor and share the same fundamental mechanism of action, they are used for different areas of laboratory research because of their substantially different pharmacokinetic profiles.

How does CJC-1295 without DAC work?

CJC-1295 without DAC acts as an agonist of the growth hormone-releasing hormone receptor (GHRHR), stimulating endogenous growth hormone synthesis and secretion through the normal hypothalamic-pituitary signalling pathway. Its four amino acid substitutions improve metabolic stability while preserving physiological receptor activation, allowing researchers to investigate pulsatile growth hormone secretion, endocrine feedback, and regulation of the GH/IGF-1 axis under conditions that closely resemble native GHRH activity.

Why were the four amino acid substitutions introduced into Modified GRF (1-29)?

Modified GRF (1-29) incorporates four targeted amino acid substitutions: D-Ala², Gln⁸, Ala¹⁵, and Leu²⁷. These were introduced to improve resistance to enzymatic degradation while preserving biological activity at the GHRH receptor, extending the peptide's biological stability without altering its fundamental mechanism of action or requiring the albumin-binding Drug Affinity Complex used in CJC-1295 with DAC.

Has CJC-1295 without DAC been studied in humans?

Dedicated human clinical studies have focused primarily on CJC-1295 with DAC rather than Modified GRF (1-29). As a result, the published evidence for CJC-1295 without DAC is derived mainly from peptide engineering, receptor pharmacology, endocrine physiology, and laboratory research that characterises its mechanism of action and biological properties.

Is CJC-1295 without DAC supplied for research use only?

Yes. Crystal Peptides supplies CJC-1295 without DAC in Europe as a laboratory research reagent. The product is intended solely for scientific investigation and is not a medicinal product, food, food supplement, or veterinary product. It is not intended to diagnose, treat, cure, or prevent any disease and must not be administered to humans or animals.

Does Crystal Peptides provide a Certificate of Analysis (COA)?

Yes. Every batch of CJC-1295 no DAC for sale by Crystal Peptides is supplied with a batch-specific Certificate of Analysis that can be traced directly to the independent testing laboratory. The COA enables researchers to verify the identity, purity, and analytical characteristics of the exact batch supplied before incorporating it into experimental work. Crystal Peptides also maintains a dedicated COA library where batch documentation can be reviewed.

How is CJC-1295 without DAC tested?

Each batch undergoes comprehensive analytical testing before release. Quality control includes HPLC purity analysis, molecular identity verification, and independent third-party testing by accredited laboratories such as Janoshik Analytical. Depending on the batch, additional analyses may include peptide content, sterility, endotoxin, and heavy metal testing, providing researchers with confidence in product identity, purity, and consistency.

How should CJC-1295 without DAC be reconstituted and stored?

CJC-1295 without DAC is supplied as a lyophilised powder and is typically reconstituted using bacteriostatic water or sterile water. The diluent should be introduced slowly down the inside wall of the vial, allowing the peptide to dissolve naturally without vigorous agitation. After reconstitution, the solution should be refrigerated at 2–8°C, while unreconstituted vials should be stored sealed, dry, protected from light, and preferably at -20°C or below. Repeated freeze-thaw cycles and prolonged exposure to elevated temperatures should be avoided to help preserve peptide integrity.

Where can I buy CJC-1295 without DAC for research purposes?

Researchers throughout the European Union can buy CJC-1295 without DAC (Modified GRF (1-29)) from Crystal Peptides. The company ships CJC-1295 without DAC throughout Europe using discreet packaging and tracked delivery services. Orders are typically dispatched promptly, with delivery times varying according to destination, and express shipping is available for many European countries.

You can review shipping options, estimated delivery times, accepted payment methods, and country-specific information on our website or contact our friendly support team for guidance before you place an order. Our goal is to make Crystal Peptides a convenient source for research peptides throughout the EU with reliable and secure delivery.