Peptide · Research Monograph · Modified GRF(1-29), protease-resistant synthetic GHRH(1-29) analog (no albumin-binding DAC)

CJC-1295

GH Half-Life Studies

Also known as CJC1295 · Mod GRF 1-29

CJC-1295 without DAC is a modified version of GHRH, the hormone that signals growth hormone release. Four amino acids are swapped to slow down enzyme breakdown. It carries no albumin linker. Because it clears quickly, researchers use this version when the timing of a signal is what they are measuring. It also serves as the comparison point against the DAC version.

Formula
C152H252N44O42
Mol. weight
3367.97 Da
Length
29 residues
CAS
863288-34-0
View product & pricing → Lot records & COAs

For laboratory research use only - not for human or animal use

CJC-1295 vial from the Eon Peptides research catalog
CJC-1295 · 5mg · catalog photograph
Available in the Eon catalog - CJC-1295 from $45.00 View certificate of analysisAccurate Test Labs · 99.18% purity · Lot CJC-091126-5

The molecule, in three dimensions

C152H252N44O423367.97
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Residues · hover to locate29 residues
Heavy atoms
238
Bonds
240
Composition
C152 N44 O42
Rings
3
Metal centre
None
Chain length
29 residues

Every heavy atom is placed from the sequence with ideal bond lengths and angles, so the connectivity is exact. The pose is idealised, an ideal helix, and is not a measured conformation. Identity for the lot in stock is confirmed by LC-MS on its certificate.

Structure viewer →

Molecular data

Molecular formulaC152H252N44O42
Molecular weight3367.97 Da
SequenceTyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Gln-Ser-Tyr-Arg-Lys-Val-Leu-Ala-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg
Sequence length29 residues
CAS / identifier863288-34-0
Physical formLyophilized Powder
Available sizes5mg

How it works

  1. Receptor Agonism

    Activation of the GHRH Receptor

    CJC-1295 (without DAC) is a synthetic GHRH(1-29) analog. Substitutions at four amino acid positions - 2, 8, 15 and 27 - make it resistant to plasma proteases, DPP-IV among them. It acts as endogenous GHRH does: the peptide binds with high affinity to GHRH receptors on somatotrophs of the pituitary and activates them.

    • Agonist selective for GHRH-R, the GHRH receptor
    • Aib in place of Ala at position 2 gives DPP-IV resistance
    • Binds pituitary somatotrophs with high affinity
  2. GH Pulses

    Secretion of GH in Pulses

    With its ~30-minute half-life, the no-DAC form differs from CJC-1295 DAC by yielding separate GH pulses, not a sustained rise. Physiological GH secretion runs at 6-12 pulses per day, a pattern this closely resembles. Research protocols use the property to examine natural GH pulse dynamics.

    • No albumin binding; half-life of ~30 minutes
    • Yields separate GH pulses of physiologic form
    • GH response peaks at 15-30 minutes
  3. IGF-1 Response

    Response of the GH/IGF-1 Axis

    Hepatic IGF-1 production rises transiently after every GH pulse. Where CJC-1295 DAC gives prolonged IGF-1 elevation, the no-DAC form gives IGF-1 responses that track each exposure, so research protocols can examine the GH pulse-to-IGF-1 relationship under tighter control.

    • Each GH pulse brings a transient IGF-1 rise
    • Prolactin and cortisol are not elevated
    • Synergy with GH secretagogues such as ipamorelin

What the research shows

  1. Endocrine Studies

    Studying GH Pulses

    Its short half-life makes the no-DAC form the GHRH analog of choice where discrete GH pulse dynamics are the subject: individual pulses can be timed and measured precisely.

  2. Comparative Pharmacology

    Comparing GHRH Analogs

    A reference standard in comparative studies that evaluate GHRH analogs on receptor binding, pharmacokinetics and downstream GH/IGF-1 axis response, set against DAC-modified variants and native GHRH.

  3. Paired Compounds

    Synergy of CJC-1295 with Ipamorelin

    CJC-1295 (GHRH-R) and ipamorelin (GHSR-1a) engage complementary pituitary pathways. Combined protocols are examined for additive GH pulse amplitude with no co-elevation of prolactin or cortisol.

  4. In Vivo Models

    Models of the GHRH Axis

    Animal models of GHRH deficiency and age-related GH decline employ Modified GRF(1-29) to study GH secretory capacity and replacement of GHRH receptor activity.

How it's tested

Every lot of CJC-1295 released to the catalog carries a third-party certificate of analysis. 4 documented lots are on file for this compound, with reported HPLC purity from 99.18% to 99.92% (mean 99.53%), issued by Accurate Test Labs and Freedom Diagnostics. 3 of 4 certificates record identity as confirmed.

Documented lots
4
Reported purity
99.18% to 99.92%
Mean purity
99.53%
Issuing labs
Accurate Test Labs, Freedom Diagnostics

All certificates in the COA library →

Frequently asked questions

How is CJC-1295 without DAC (Modified GRF 1-29) classified and structured?

Known also as Mod GRF or Modified GRF(1-29), CJC-1295 without DAC is classified as a synthetic 29-residue analog of GHRH (growth hormone-releasing hormone). Four of its positions carry substitutions that resist cleavage by the protease DPP-IV, which moves the half-life from about 7 minutes for native GHRH to roughly 20-30 minutes. The Drug Affinity Complex (DAC), the albumin-binding modification present in CJC-1295 DAC, is absent here, and GH stimulation is therefore pulsatile and not sustained.

What structural feature separates the no-DAC form from CJC-1295 DAC, and what follows from it?

One structural feature separates them: whether the Drug Affinity Complex (DAC), a maleimidopropionic acid group carried on Lys8, is present. The form lacking DAC has a ~30 minute half-life, gives discrete GH pulses that mirror physiological pulse patterns, and needs frequent repeated exposures for a sustained signal. The DAC form binds albumin, reaching a half-life of 5.8-8.1 days; GH/IGF-1 elevation is sustained, and research protocols can space exposures at extended intervals.

What is the physiological basis for research interest in pulsatile GH release?

The anterior pituitary secretes endogenous growth hormone in discrete pulses, 6-12 per day, most of them during slow-wave sleep. Compared with continuous exposure, pulsatile secretion is associated with different downstream effects, with differences in receptor sensitivity, IGF-1 production and anabolic signaling. Because its half-life is short, CJC-1295 without DAC suits research protocols that must study or preserve this physiological pulsed pattern instead of holding GH continuously elevated.

On what receptor-level rationale is CJC-1295 (no DAC) studied together with ipamorelin?

The two compounds address distinct receptor systems. Ipamorelin activates GHSR-1a (Growth Hormone Secretagogue Receptor 1a), whereas CJC-1295 (no DAC) activates GHRH-R, the GHRH receptor on somatotrophs of the pituitary, and the intracellular pathways involved are complementary. With simultaneous activation of both, recorded GH pulse amplitude has exceeded that of either compound alone. The CJC-1295/Ipamorelin research blend rests on that additive interaction.

What is the regulatory and clinical-trial status of CJC-1295 without DAC?

No FDA approval exists for CJC-1295 without DAC in any indication. For this specific form, no standalone Phase 3 clinical trial has been completed. It is a research compound, available solely for in vitro laboratory use, and human therapeutic use is not intended.

What governs the storage stability of CJC-1295 (no DAC)?

For long-term stability the lyophilized powder is kept at -20°C, protected from light, and spared repeated freeze-thaw cycles. Lacking the DAC modification, the peptide in solution is more susceptible to degradation by DPP-IV, which makes the lyophilized material the more stable of the two forms.

For laboratory research use only. Not a drug, supplement, or medical product; not for human or animal use. All findings referenced are from published preclinical/laboratory research.