What it is
CJC-1295 without DAC, also called Mod GRF 1-29, is a synthetic 29-amino-acid analog of growth hormone releasing hormone. It carries four substitutions on the human GRF(1-29) backbone that slow enzymatic breakdown, but it lacks the albumin-binding DAC linker, so its action stays short. It appears in endocrinology research on the pituitary growth hormone axis.
How it works
It binds the GHRH receptor on pituitary somatotroph cells and triggers a pulse of growth hormone release. The amino acid substitutions are thought to reduce cleavage by dipeptidyl peptidase-4, extending activity compared with unmodified GHRH(1-29).
Regulatory status
- Cosmetic ingredient
- Research compound
- In clinical trials
- Approved medicine
Not approved as a medicine by the FDA or the EMA. Some are registered in individual countries. Supplied for laboratory research only.
What published research is studying
- Stimulation of pituitary growth hormone release through the GHRH receptor (in vitro and rodent work)
- Restoration of the growth hormone and IGF-I axis in older adults (small controlled trials of GHRH(1-29) analogs)
- Resistance of modified GRF(1-29) sequences to enzymatic degradation
- Body composition measures such as lean mass and skin thickness in ageing research
Key findings
In Sprague Dawley rats, a tetrasubstituted hGRF(1-29) derivative produced a 4-fold larger 2-hour growth hormone area under the curve than unmodified hGRF(1-29). It also resisted dipeptidyl peptidase-4 in vitro.
Jetté L et al., Endocrinology 2005In a single-blind, randomized, placebo-controlled study, 19 adults aged 55 to 71 years received a GHRH(1-29) analog nightly for 16 weeks. Nocturnal growth hormone, IGF-I and IGFBP-3 rose significantly.
Khorram O, Laughlin GA, Yen SS, J Clin Endocrinol Metab 1997In that same 16-week study, skin thickness increased in both sexes, while lean body mass and insulin sensitivity increased only in the men.
Khorram O, Laughlin GA, Yen SS, J Clin Endocrinol Metab 1997In 10 healthy men aged about 68 years, GHRH(1-29) given twice daily for 14 days raised 24-hour growth hormone and IGF-I. Levels no longer differed significantly from those of healthy young men.
Corpas E et al., J Clin Endocrinol Metab 1992
What the studies measured
Study durations
- GHRH(1-29) analog study in adults aged 55 to 71: 16 weeks of nightly injections after a 4-week placebo run-in (Khorram 1997).
- GHRH(1-29) study in healthy older men: two 14-day treatment periods separated by 14 days without treatment (Corpas 1992).
- Rat work on modified hGRF(1-29) analogs: single subcutaneous doses with plasma sampling from 15 minutes to 72 hours (Jetté 2005).
Endpoints
- Peak and 24-hour integrated growth hormone concentrations
- Growth hormone area under the curve after a single dose
- Serum IGF-I and IGFBP-3
- Lean body mass and fat mass by DXA
- Skin thickness
How strong is the evidence?
No published human trial has tested this exact tetrasubstituted GRF(1-29) sequence. The human data come from small studies of closely related GHRH(1-29) analogs, and the molecule-specific work is preclinical.
Common questions
Is CJC-1295 without DAC an approved medicine?
Research compound. Not approved as a medicine by the FDA or the EMA. Some are registered in individual countries. Supplied for laboratory research only.
How much human research is there on CJC-1295 without DAC?
No published human trial has tested this exact tetrasubstituted GRF(1-29) sequence. The human data come from small studies of closely related GHRH(1-29) analogs, and the molecule-specific work is preclinical.
Does UU supply CJC-1295 without DAC?
Yes, as premium-grade research material for laboratory use. Every batch is tested by an independent lab and the certificate of analysis is published.