CJC-1295 with DAC: Structure, Research Overview and Specifications
CJC-1295 with DAC is a long-acting synthetic analogue of growth-hormone-releasing hormone (GHRH). It combines the enzyme-resistant Modified GRF (1-29) sequence with a drug affinity complex (DAC) that binds to albumin in the blood, extending its half-life from minutes to days. This page explains how the DAC works, summarises the published research and gives the specifications of the material we supply.
For in vitro research use only. Not for human or animal use. Nothing on this page is medical advice.
What is CJC-1295 with DAC?
CJC-1295 was developed by the Canadian company ConjuChem Biotechnologies as a long-acting GHRH analogue. Its peptide backbone is GRF (1-29), the active first 29 amino acids of GHRH, with four substitutions (D-Ala2, Gln8, Ala15, Leu27) that make it resistant to enzymatic breakdown. This backbone is the same as CJC-1295 without DAC (Mod GRF 1-29).
What sets CJC-1295 with DAC apart is an extra modified lysine at the C-terminus. It carries a reactive maleimide group, the “drug affinity complex”, which attaches the peptide to albumin. This changes the compound from a short pulse into a sustained GHRH-receptor stimulus.
How the DAC works
- Reactive linker. A lysine at position 30 is modified with a maleimidopropionyl (MPA) group.
- Albumin conjugation. In blood, the maleimide group reacts with a free thiol on serum albumin, forming a stable bond.
- Protected from clearance. Bound to albumin, the peptide avoids rapid kidney filtration and enzymatic degradation.
- Extended half-life. In humans, the reported half-life is about 6 to 8 days, compared with minutes for native GRF (1-29).
CJC-1295 with DAC vs without DAC
| CJC-1295 with DAC | CJC-1295 no DAC (Mod GRF 1-29) | |
|---|---|---|
| Backbone | Tetrasubstituted GRF (1-29) | Tetrasubstituted GRF (1-29) |
| C-terminal extension | Lys(MPA) drug affinity complex | None |
| Albumin binding | Yes | No |
| Reported half-life | About 6–8 days in humans | Around 30 minutes |
| Stimulus profile | Sustained elevation of GH and IGF-1 | Short, pulse-like stimulus |
| Molecular weight | ≈ 3647.3 g/mol | ≈ 3367.9 g/mol |
Chemical data
| Name | CJC-1295 with DAC |
|---|---|
| Structure | Tetrasubstituted GRF (1-29)-NH2 (D-Ala2, Gln8, Ala15, Leu27) with an additional C-terminal Lys(ε-maleimidopropionyl) |
| Molecular formula | C165H269N47O46 |
| Molecular weight | ≈ 3647.3 g/mol |
| CAS number | 446262-90-4 |
| Developer | ConjuChem Biotechnologies |
| Appearance | White lyophilised powder |
| Available sizes | CJC-1295 with DAC 5mg |
Mechanism of action
Like other GHRH analogues, CJC-1295 binds GHRH receptors on pituitary somatotroph cells and stimulates the synthesis and release of the body’s own growth hormone. Because albumin binding keeps it in circulation for days, it gives a prolonged stimulus. This raises baseline GH and IGF-1 levels over an extended period, rather than producing a single short pulse.
What the published research shows
Study in healthy adults
Teichman et al. (2006, Journal of Clinical Endocrinology & Metabolism) studied CJC-1295 in healthy adults aged 21–61. After a single administration, mean plasma GH concentrations rose 2- to 10-fold for 6 days or more, and IGF-1 rose 1.5- to 3-fold for 9–11 days. The estimated half-life was about 6–8 days.
Pulsatility
Follow-up research reported that, despite continuous stimulation, GH secretion stayed pulsatile, with baseline (trough) GH levels raised. This suggests normal feedback mechanisms remained partly active.
Clinical development
CJC-1295 entered phase 2 trials, but development was discontinued after the death of a trial participant. The death was attributed to pre-existing coronary artery disease and considered unrelated, but the programme was stopped as a precaution.
Limitations of the evidence
- Published human data are limited to small, short-term studies.
- Clinical development was halted, so there are no long-term efficacy or safety data.
- Sustained elevation of GH and IGF-1 differs from natural pulsatile physiology, and its long-term effects have not been established.
Regulatory status
CJC-1295 is not a licensed medicine in the UK and has not been approved by the MHRA, FDA or EMA. GHRH and its analogues are prohibited in sport under the WADA Prohibited List (S2). Sterling Research supplies CJC-1295 with DAC only as a research reagent for in vitro laboratory use. It must not be used in humans or animals.
Storage and handling in the lab
- Store lyophilised powder at −20 °C, sealed and protected from light and moisture.
- Let the vial reach room temperature before opening to limit condensation.
- The maleimide group is reactive towards thiols. Avoid thiol-containing buffers and reducing agents unless your protocol requires them.
- Prepare solutions to your laboratory’s validated protocols, with appropriate PPE and aseptic technique.
Quality
Every batch of CJC-1295 with DAC we supply is independently tested by Janoshik for purity and identity before it is released for sale.
Related research compounds
Frequently asked questions
What does DAC stand for?
DAC stands for drug affinity complex: a maleimide-modified lysine that lets the peptide bind to albumin in the blood, greatly extending its half-life.
What is the difference between CJC-1295 with DAC and without DAC?
Both share the same modified GRF (1-29) backbone. The DAC version has an extra albumin-binding lysine, giving a half-life of about 6–8 days. The no-DAC version (Mod GRF 1-29) lasts around 30 minutes and gives a short, pulse-like stimulus.
What is the half-life of CJC-1295 with DAC?
In the published study in healthy adults, the estimated half-life was about 6 to 8 days.
What is the CAS number of CJC-1295 with DAC?
The CAS number for CJC-1295 (with DAC) is 446262-90-4, with molecular formula C165H269N47O46.
Is CJC-1295 approved as a medicine?
No. Clinical development stopped during phase 2, and it is not approved by the MHRA, FDA or EMA.
References
- Teichman SL, 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. doi:10.1210/jc.2005-1536
- CJC-1295. Structure, DAC technology, development history and identifiers
This page is for scientific information only. Sterling Research Group Ltd supplies CJC-1295 with DAC strictly for in vitro laboratory research. Not for human or animal use, and not for diagnostic or therapeutic purposes.