Mod GRF 1-29 and CJC-1295: Are They the Same?

Mod GRF 1-29 and CJC-1295 without DAC are the same compound. CJC-1295 with DAC is a different molecule. The confusion arises because the research supply market uses "CJC-1295" to name both, often without any clarification. The distinction comes down to one structural feature: the DAC, or Drug Affinity Complex, and whether it is present in the peptide.

What Mod GRF 1-29 Is

Mod GRF 1-29, also written Modified GRF 1-29, is a modified version of the first 29 amino acids of human GHRH — growth hormone-releasing hormone. The modification consists of four amino acid substitutions at specific positions in the chain. Those substitutions are designed to improve the peptide's stability against enzymatic degradation, compared to the original GHRH(1-29) fragment.

The result is a short-acting analog. Studies in animal models measure plasma clearance in minutes after administration. That positions it as a brief-acting peptide within the family of GHRH analogs investigated in laboratory settings.

In supplier catalogues for research materials, Mod GRF 1-29 and CJC-1295 without DAC are the same product. Both names coexist because the research literature adopted "Modified GRF 1-29" while the market took "CJC-1295 without DAC" as a direct synonym.

What CJC-1295 Is

CJC-1295 was developed by ConjuChem Biotechnologies. The compound incorporates a technology called the Drug Affinity Complex (DAC): a chemical moiety that covalently bonds to serum albumin, the most abundant protein in plasma.

That bond converts the peptide into a circulating reservoir. Studies by ConjuChem in phase I and II trials — including the work by Teichman and colleagues published in the Journal of Clinical Endocrinology & Metabolism — recorded sustained elevations of GH and IGF-1 over several days from a single subcutaneous dose in healthy adults. The measured half-life in those studies exceeded six days.

CJC-1295 with DAC is, from a chemical standpoint, a different compound from Mod GRF 1-29. Both share the 29-amino-acid base, but the DAC distinguishes them in both structure and pharmacokinetic behavior.

The Practical Difference: The DAC

The distinction between the two compounds reduces to one fact: does it have the DAC or not?

• Without DAC: the peptide clears rapidly from plasma, with a half-life measured in minutes. This is what is sold as Mod GRF 1-29 or CJC-1295 without DAC.
• With DAC: albumin binding extends the half-life to days. This is what ConjuChem named CJC-1295.

What creates confusion is that many suppliers sell the compound without DAC under the name "CJC-1295," omitting the "without DAC" or "no DAC" qualifier. When the catalogue does not clarify, it is not possible to know which compound is being supplied without reading the certificate of analysis or the lot data sheet.

A supplier that does not distinguish the two molecules by name and in documentation does not provide transparency about what it supplies. In research settings that matters: protocols designed for CJC-1295 with DAC are not applicable to the compound without DAC, and vice versa.

How to Identify Which Compound Is Which in Documentation

A certificate of analysis issued by an independent laboratory should state the compound's IUPAC name or the full amino acid sequence with the modifications applied. If the compound is Mod GRF 1-29 or CJC-1295 without DAC, the material description will contain no reference to the Drug Affinity Complex. If it is CJC-1295 with DAC, the DAC moiety appears named in the documentation.

The name of the laboratory that issued the report, the task number of the analysis, and the date of the analysis are the three pieces of information that allow independent verification of the material's identity. Janoshik Analytical is one of the laboratories that publishes its reports with a verifiable task number. The current lot reports are available on PeptoClinic's quality page.

If a supplier does not provide a CoA issued by an external laboratory with an identifiable task number, there is no way to confirm what compound the vial contains.

Alternative Names in the Literature

The proliferation of names for the same compound is characteristic of synthetic peptide research, where commercial nomenclature, the original molecule name, and research aliases coexist without standardization.

For the compound without DAC, the most common names are:

• Mod GRF 1-29
• Modified GRF 1-29
• CJC-1295 without DAC / CJC-1295 no DAC
• Tetrasubstituted GRF (1-29)

For the compound with DAC:

• CJC-1295
• CJC-1295 with DAC
• CJC-1295 DAC

The presence of the word "DAC" is the clearest marker. Its absence does not guarantee the compound is the without-DAC version — explicit confirmation in the lot documentation is still required.

Relationship to Other GHRH Analogs

The GHRH analog family includes several compounds with distinct sequences and pharmacological profiles. Sermorelin is the GHRH(1-29) fragment without the four substitutions characteristic of Mod GRF 1-29, giving it an even shorter half-life. Tesamorelin is another GHRH analog that holds FDA approval for a specific human indication, which places it in a different regulatory category.

Ipamorelin is not a GHRH analog but a selective ghrelin receptor agonist. It acts on a different receptor but converges on GH secretion. It is frequently studied in preclinical research alongside GHRH analogs because it acts on a distinct pathway within the same axis.

The choice between GHRH analogs for a research protocol depends on the pharmacokinetic profile the experimental design requires, not on the equivalence between commercial names.

Research Material: Regulatory Framing

PeptoClinic supplies CJC-1295 without DAC strictly for laboratory research use (Research Use Only, RUO): in vitro and preclinical models.

None of these compounds hold approval from the FDA, ANMAT, or any equivalent regulatory authority for human or veterinary use. PeptoClinic is not a pharmacy, a clinic, or a source of guidance on administration, dosing, or protocols for people. Requests of that nature fall outside the scope of this company's services.

Material is quoted with its lot certificate of analysis issued by an external laboratory and with customs documentation for import as laboratory reference material. Available destinations and the quotation process are on the shipping page.