CJC-1295 DAC vs No DAC (Mod GRF 1-29): Key Differences

By Editorial team. Updated Oct 15, 2026. Awaiting expert review

“CJC-1295” is sold as two different molecules, and the name alone doesn’t say which [2]. CJC-1295 with DAC is the version described in the original research and tested in published human trials: a modified 29-amino-acid fragment of growth hormone-releasing hormone (GHRH) with a drug affinity complex (DAC) that binds it to albumin in the blood, so it lasts for days [1, 2, 3]. CJC-1295 without DAC, also sold as Mod GRF 1-29, is the same modified fragment without that complex, and no controlled human studies of it have been published [2]. Evidence for one doesn’t transfer to the other.

What each one is

Both start from the first 29 amino acids of human GHRH, with four of them swapped to make the peptide more resistant to breakdown by enzymes [1, 2].

With DAC. CJC-1295 as first described carries one extra piece: a lysine at the end with a maleimide group attached [1]. That group bonds to serum albumin. In rats, CJC-1295 was still present in plasma beyond 72 hours [1], and in healthy adults its estimated half-life was 5.8 to 8.1 days [3]. A 2026 review calls this addition the drug affinity complex and says it is what markedly prolongs exposure [2].

Without DAC. The same review names the version without it “CJC-1295 without DAC” or “Mod GRF 1–29”, and says no peer-reviewed human study has reported its half-life [2].

How the evidence compares

The DAC form was tested in two small randomized, placebo-controlled trials in healthy adults, published in 2006. After a single administration, growth hormone levels rose 2- to 10-fold for six days or more and IGF-I levels 1.5- to 3-fold for 9 to 11 days, and no serious adverse reactions were reported [3]. A 2026 review classes this as phase I evidence, with no controlled efficacy data and no long-term safety data [2].

The version without DAC “remains essentially uncharacterised in the peer-reviewed human literature”, according to the same review: no controlled clinical studies have evaluated it, and claims made for it are extrapolated from related compounds, mainly sermorelin (GHRH(1–29)), and from non-academic sources [2].

Regulation and sport

Neither form is approved as a medicine by major regulators, according to the same review [2], and FDA’s list of compounding safety risks names CJC-1295 without distinguishing the two forms, citing serious adverse events including increased heart rate and a systemic vasodilatory reaction [6]. WADA’s list names CJC-1295 and prohibits GHRH analogues in general at all times [7].

How we price them

Because they are different molecules, we price them separately: CJC-1295 with DAC and CJC-1295 without DAC. A listing that says only “CJC-1295”, with no mention of DAC, could be either, so we treat it as ambiguous and leave it out of both comparisons.

Quality risks when buying

Research-grade vials of either form come from unregulated supply chains [2], and the label isn’t proof of the contents [5]. In 2009, a laboratory analyzing seized products for Norwegian police and customs found a 29-amino-acid peptide consistent with one then marketed as CJC-1295 [4]: that is the length of the version without DAC, not the molecule with the extra lysine described in the original research [1]. Analysis of products seized by Danish customs also found modified GRF 1-29 with an extra glycine added [5].

So ask for a batch certificate of analysis (COA) that names the form, gives the sequence and confirms identity by mass spectrometry, the method these laboratories used [4, 5]. Our guides explain how to read a COA, how to check a vendor and what “research use only” means.

For more, see our CJC-1295 with DAC overview, our CJC-1295 without DAC page (legal status and prices; no full overview yet), and our comparison of CJC-1295 and sermorelin.