CJC-1295

Key facts

01 What Is CJC-1295?

It is a synthetic peptide built on the first 29 amino acids of human growth hormone-releasing hormone (GHRH), the hypothalamic hormone first isolated and sequenced in 1982 ^[1]. Those 29 residues, which FDA GSRS records as GRF (1-29) amide under the name sermorelin, are the starting point for several analogues, and the peptide on this page is one of them.

The 2005 paper that first identified the compound describes a tetrasubstituted form of hGRF(1-29) with an extra lysine at the C-terminus, and that lysine carries an N-epsilon-3-maleimidopropionamide group ^[2]. In animal models, the reactive group was designed to bind the free thiol on cysteine 34 of serum albumin after administration, extending the peptide's plasma half-life ^[2]. Its developers named the linker a drug affinity complex, or DAC.

Vinnix doesn't sell this peptide on its own. It's one of the two peptides in the CP10 blend with ipamorelin, and this page is a reference-library entry.

02 CJC-1295 With DAC vs. Without DAC

These are two different molecules. The DAC version has an extra C-terminal lysine bearing the maleimidopropionyl group; the no-DAC version stops at residue 29.

They share most of their sequence but differ by a whole modified residue, so mass spectrometry separates them easily. A product record should always say which one is present. For Vinnix CP10, the form present (with or without DAC) will be stated on the product record and on the batch COA when published.

03 CJC-1295 Product Specifications

With no standalone Vinnix SKU, the specifications below are given as compound data plus the one Vinnix product that contains the peptide.

04 CJC-1295 Product Identity

Two things define the peptide's identity: its sequence and its C-terminal modification. FDA GSRS records it under UNII 62RC32V9N7 with CAS 446262-90-4.

What is the peptide sequence?

GSRS gives the backbone in one-letter code as YaDAIFTQSYRKVLAQLSARKLLQDILSRK, with the lower-case a marking D-alanine (see one-letter vs. three-letter amino acid codes). The 3-maleimidopropionyl group sits on the side-chain amine of the final lysine, and the C-terminus is amidated.

Set against native human GRF(1-29), as recorded for sermorelin (YADAIFTNSYRKVLGQLSARKLLQDIMSR), the analogue has four substitutions:

Those four changes are why the paper calls it a tetrasubstituted GRF(1-29) ^[2]. The same study reported that its albumin conjugates had enhanced in vitro stability against the enzyme dipeptidyl peptidase IV ^[2]. Notation conventions are explained in the peptide sequences guide.

05 CJC-1295 Terminology

You'll see several names for these materials, and they don't all point to one compound.

• CJC-1295 / CJC-1295 with DAC: the molecule described in the 2005 paper and registered in PubChem and GSRS.
• Without DAC / no DAC: catalog names for the 29-residue tetrasubstituted analogue without the lysine-maleimide extension.
• Mod GRF (1-29) / modified GRF 1-29: another catalog name for the no-DAC version.
• Sermorelin / GRF (1-29): the unsubstituted native 1-29 sequence, a different molecule.
• Tesamorelin: a modified full-length 1-44 GHRH analogue, also a different molecule.

If a label just says "CJC 1295", look at the batch mass spectrometry to see which molecule you have. Related reference pages: Sermorelin and Tesamorelin.

06 CJC-1295 Research Literature

There isn't much published on this peptide: one discovery study in rats, one animal study in knockout mice and two human pharmacology papers from 2006. All of them used the DAC version. In vitro vs. in vivo research explains how those study types differ.

How has the peptide been studied?

• Background (in vitro and biochemistry): GHRH, the parent hormone, was isolated and sequenced from a human pancreatic tumor ^[1].
• Discovery (in vitro and animal): researchers compared three maleimido derivatives of hGRF(1-29) for stability, activity in cultured rat pituitary cells, GH secretion in rats and persistence in plasma. They selected this derivative and showed it bound to albumin in rat plasma ^[2].
• Animal model: a study in GHRH knockout mice investigated growth and pituitary parameters with the peptide ^[3].
• Human pharmacology (clinical): two randomized, placebo-controlled, double-blind ascending-exposure studies in healthy adults. One investigated pharmacokinetics and plasma GH and IGF-I concentrations ^[4]; the other examined whether the pulsatile pattern of GH secretion persisted ^[5].

Preclinical findings do not establish safety or effectiveness in humans. The early human studies characterized pharmacology in small groups of volunteers; they did not establish clinical outcomes. The peptide is not an FDA-approved medicine. And because no published study covers the no-DAC version in comparable depth, results for one form shouldn't be applied to the other.

07 CJC-1295 Analytical Documentation

Analysis starts with identity. Mass spectrometry is the most direct way to tell the DAC version from the no-DAC version, and HPLC follows to assess purity.

• Mass spectrometry: the DAC version has a molecular weight of 3647.2 g/mol; the no-DAC version is lighter because it lacks the modified lysine. See mass spectrometry for peptides.
• HPLC: reports the main peak as a share of detected UV area. In CP10, the two peptides elute as separate peaks and should be reported on separate lines.
• Maleimide stability: the maleimide group can react with thiols, so related impurities may show up. LC-MS is the best way to identify them.

CP10 batch reports will be listed in the Vinnix COA Library as they're published. For the blend, a useful certificate of analysis gives each of the two peptides its own line, with an observed mass. Peptide testing and analysis covers methods in general, and the companion peptide has its own Ipamorelin page.

REFScientific references

1. Guillemin R, Brazeau P, Böhlen P, et al. Growth hormone-releasing factor from a human pancreatic tumor that caused acromegaly. Science. 1982;218(4572):585-587. PubMed 6812220
   in vitro (isolation and sequencing)
2. 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. PubMed 15817669
   in vitro and animal
3. Alba M, Fintini D, Sagazio A, et al. Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout mouse. Am J Physiol Endocrinol Metab. 2006;291(6):E1290-E1294. PubMed 16822960
   animal
4. Teichman SL, Neale A, Lawrence B, et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805. PubMed 16352683
   human clinical pharmacology, randomized placebo-controlled
5. Ionescu M, Frohman LA. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. J Clin Endocrinol Metab. 2006;91(12):4792-4797. PubMed 17018654
   human clinical pharmacology