CJC-1295 W/Dac

Origin and structure

CJC-1295 with DAC was developed by ConjuChem, a biotech company in Montreal. Its idea was to attach a reactive chemical group, the drug affinity complex (DAC), to a peptide so that after injection the peptide bonds to albumin, the most abundant protein in blood, and shares its long lifespan. In a 2005 rat study the company compared three such versions of GHRH(1-29), the active first 29 amino acids of the hypothalamic hormone that tells the pituitary to release growth hormone, and selected the one it named CJC-1295.

Structurally it is GHRH(1-29) with four amino acids swapped to resist breakdown (D-alanine at position 2, glutamine at 8, alanine at 15 and leucine at 27), plus an extra lysine at the end that carries a maleimidopropionyl group. That group reacts with cysteine 34 of albumin. The result is a 30-amino-acid peptide (C165H269N47O46, about 3,647 g/mol) that circulates bound to albumin. Without the extra lysine, the 29-amino-acid core is the compound sold as CJC-1295 without DAC or Mod GRF 1-29.

How it works

CJC-1295 acts on the same receptor as natural GHRH, on the growth-hormone-producing cells of the anterior pituitary. Growth hormone in turn makes the liver release IGF-1, which carries many of its effects. Natural GHRH(1-29) is broken down quickly, mainly by the blood enzyme DPP-IV: in rats it was detectable in plasma for about an hour after injection, whereas CJC-1295 was still present after 72 hours. In healthy adults its estimated half-life was 5.8 to 8.1 days.

A constant signal could in principle flatten the body's natural growth-hormone pulses. In a 2006 study of 12 healthy men it did not: one week after a single injection the pulses kept their frequency and size, but the trough levels between pulses rose 7.5-fold, mean growth hormone rose 46% and IGF-1 45%. The authors pointed to the raised baseline, not bigger pulses, as the likely driver of the IGF-1 increase.

Because it works through the pituitary, it depends on a pituitary that can still make growth hormone. The FDA noted in its 2024 review that results from healthy volunteers may not carry over to people with growth hormone deficiency, the use pharmacies had proposed.

Is CJC-1295 with DAC approved?

No. No regulator has authorised CJC-1295 in any form: not the EMA, not the FDA, and it is not a registered medicine in the Netherlands. Development went no further after ConjuChem's phase 2 trial was terminated in 2006, and no later trial of CJC-1295 has been registered on ClinicalTrials.gov. In the Netherlands it may not be sold or promoted for use in people; it is available only as research material, which is the basis our shop operates on.

In the United States the question has been whether pharmacies may compound it. CJC-1295 was in Category 2 of the FDA's list of bulk substances that may present significant safety risks until the nominations behind it were withdrawn; the FDA's page still records serious adverse events including a raised heart rate and a systemic vasodilatory reaction. The FDA then reviewed five CJC-1295 substances on its own initiative, and on 4 December 2024 its Pharmacy Compounding Advisory Committee voted 13 to 0 against adding each of the three DAC forms (free base, acetate and trifluoroacetate) to the list of substances pharmacies may compound. The two forms without DAC were rejected 13 to 0 and 12 to 1. With no place on that list, no pharmacopoeia monograph and no approved medicine that contains it, US pharmacies have no basis to compound it under section 503A.

In sport it is prohibited at all times. The 2026 WADA Prohibited List names CJC-1295 as an example in class S2.2.4, growth-hormone-releasing factors, and the list applies in the Netherlands through the Council of Europe Anti-Doping Convention.

What the research shows

Everything known about CJC-1295 with DAC in humans comes from short pharmacology studies of ConjuChem's compound, published in 2006, and a 2009 analysis of blood samples from 11 of the men in one of them. By the FDA's count, 63 healthy adults received it in these studies, 55 of them men, and 46 had a single injection. None measured muscle, fat, strength, recovery, sleep or ageing. A 2026 review in Frontiers in Endocrinology classed the evidence as phase 1 pharmacology in healthy adults, with no controlled efficacy data. The studies:

• Jetté et al. 2005 (rats): of three albumin-binding versions of GHRH(1-29), CJC-1295 gave four times the growth-hormone response of GHRH(1-29) over two hours and stayed in the blood beyond 72 hours.
• Alba et al. 2006 (mice): in mice lacking their own GHRH, 2 µg daily for five weeks produced normal weight and length; the same dose every 48 or 72 hours improved growth but did not fully normalise it.
• Teichman et al. 2006 (healthy adults aged 21 to 61): two randomised, double-blind, placebo-controlled trials lasting 28 and 49 days. One injection raised mean growth hormone 2- to 10-fold for six days or more and IGF-1 1.5- to 3-fold for 9 to 11 days; after repeated doses IGF-1 stayed above baseline for up to 28 days. IGF-1 went above the normal range only at the highest dose, 250 µg/kg.
• Ionescu and Frohman 2006 (12 men aged 20 to 40): one week after a single injection, growth-hormone pulses were unchanged in frequency and size, trough levels were 7.5 times higher, mean growth hormone 46% higher and IGF-1 45% higher.
• Phase 2 trial in HIV-associated abdominal obesity (NCT00267527): randomised, double-blind, 12 weeks of weekly injections against placebo, with 192 participants enrolled according to ConjuChem (the registry lists 120). It was terminated in 2006 after a participant died, and no results have been posted or published.

Side effects and warnings

Side effects were frequent in the 2006 trials, though mostly short-lived. In the single-dose trial 33 of 35 people on CJC-1295 reported at least one adverse event, against 2 of 7 on placebo. About 70% had injection-site reactions (irritation, redness, hardening, pain or itching), 63% headache (14% on placebo), 43% diarrhoea and 30% a vasodilatory reaction with flushing, warmth and a brief drop in blood pressure; most of these were more common at 125 and 250 µg/kg. In the multiple-dose trial flushing was reported in 40% after low-dose and 100% after high-dose injections, two people had dizziness with low blood pressure after their first dose, and one had brief involuntary leg-muscle contractions with some loss of coordination. The 12-man study recorded a dose-dependent rise in heart rate. No serious adverse reactions were reported, and the trials found no consistent changes in glucose, liver tests or ECGs.

The phase 2 trial is the only exposure in patients. According to the reports the FDA reviewed, one participant developed chest discomfort two hours after an 11th weekly injection, an ECG confirmed a heart attack, and the participant died about an hour later. The attending physician's most likely explanation was undiagnosed coronary artery disease with a ruptured plaque. The trial was stopped and its data have never been published, so how often side effects occurred in patients is unknown.

Animal and laboratory data add further cautions. Repeated injections caused bleeding, inflammation and tissue death at the injection site in rats and dogs. In mouse pituitary cells and in mice, a long-acting GHRH analogue that the FDA identifies as CJC-1295 with DAC increased markers of DNA damage, and with no cancer studies done, the FDA could not rule out pituitary overgrowth or tumours with long-term use. Its review also noted that the reactive group might bind proteins other than albumin. There are no long-term human safety data.

With DAC, without DAC: the naming confusion

In ConjuChem's papers, CJC-1295 meant the molecule with the DAC. The name has since spread to the 29-amino-acid core without it, now sold as CJC-1295 without DAC or Mod GRF 1-29. The FDA treats the two as different active substances that are not interchangeable, and found that the pharmacy nominations it reviewed did not make clear which one was meant. When Norwegian anti-doping chemists analysed an unidentified preparation for police and customs in 2009, they found a 29-amino-acid peptide matching what was being marketed as CJC-1295: the core without the DAC.

The difference matters for the evidence. All the human data on this page concern the DAC form. The FDA noted that its pharmacology cannot be extrapolated to CJC-1295 without the DAC, and the 2026 Frontiers review found no controlled human study of the form without DAC at all. Findings for one should not be read across to the other; CJC-1295 without DAC has its own article in this wiki.

Frequently asked questions

What is the difference between CJC-1295 with and without DAC?

The DAC is an extra lysine carrying a group that bonds to albumin in the blood, which stretches the half-life to 5.8 to 8.1 days in healthy adults. The 29-amino-acid core without it (Mod GRF 1-29) lacks that anchor, and no half-life in humans has been published for it. All controlled human data are for the DAC form, and the FDA treats the two as different, non-interchangeable substances.

Is CJC-1295 with DAC legal in the Netherlands?

It is not a registered medicine and may not be sold or promoted for use in people. It can be bought and sold as research material, which is the basis for our shop. For athletes it is a prohibited substance at all times.

Is CJC-1295 banned in sport?

Yes, in and out of competition. The WADA Prohibited List names CJC-1295 in class S2.2.4, growth-hormone-releasing factors, alongside sermorelin and tesamorelin. Because the class covers GHRH and all its analogues, the form without DAC is prohibited too.

Does CJC-1295 with DAC build muscle or burn fat?

No published study has answered that. The human studies measured growth hormone and IGF-1 for a few weeks; none measured muscle mass, fat, strength or recovery. The one trial that looked at fat, in people with HIV, was stopped part-way and has never been published.

Why did development stop?

ConjuChem's phase 2 trial was terminated in 2006 after a participant died of a heart attack shortly after an 11th weekly injection. The attending physician considered undiagnosed coronary artery disease the most likely cause, but the trial did not restart, its results were never published, and no later trial of CJC-1295 has been registered.

How long does CJC-1295 with DAC stay in the body?

In healthy adults the estimated half-life was 5.8 to 8.1 days, the drug stayed measurable for 10 to 13 days, and IGF-1 remained above baseline for 9 to 11 days after a single injection.

Storage and handling

Store according to product-label instructions and batch handling notes. Lyophilized research peptides are commonly kept dry, protected from light, and handled with clean laboratory technique.

References

Checked against these sources on 28 October 2026.