CJC-1295 without DAC benefits and areas of research

There is no measured human benefit to report, because there is no published human study of this compound. Everything written about CJC-1295 without DAC — the growth hormone pulse, the IGF-1 rise, the pairing with a GHRP — is borrowed either from the DAC version or from growth hormone–releasing hormone generally. FDA's 2024 evaluation is blunt about this: reviewers could not identify studies establishing whether CJC-1295 free base is even pharmacologically active, and stated that "the pharmacological profile of the CJC-1295 DAC cannot be extrapolated to CJC-1295 without the DAC modification" (FDA briefing document, PCAC December 2024).

The peptide sold as "CJC-1295 no DAC" or "modified GRF 1-29" is a 29-amino-acid analogue of GHRH — the natural hormone's first 29 residues — carrying four deliberate substitutions at positions 2, 8, 15 and 27 (Jetté et al., Endocrinology 2005). Each was introduced for a chemical reason rather than a pharmacological one:

• D-alanine at position 2 — peptides carrying D-alanine here resist dipeptidyl peptidase-IV, the plasma enzyme that inactivates native GHRH(1-29) within minutes.

• Glutamine at position 8 — replaces an asparagine prone to rearrangement or amide hydrolysis.

• Leucine at position 27 — replaces a methionine prone to oxidation.

This is the same backbone as CJC-1295 with DAC, minus the maleimido-lysine group that binds albumin. FDA lists its molecular formula as C₁₅₂H₂₅₂N₄₄O₄₂ and its molecular weight as 3,367.95 g/mol — and notes that the entry for it in the Global Substance Registration System is internally inconsistent, with the chemical structure of the DAC version filed under the free base's name. That kind of naming confusion is not academic when it determines what a supplier ships.

Modified GRF 1-29 entered public awareness through a seizure, not a trial. In 2009, Norwegian police and customs submitted an unknown pharmaceutical preparation to the national doping control laboratory; mass spectrometry identified a 29-amino-acid C-terminally amidated peptide matching CJC-1295, and the authors noted the preparation did not contain DAC (Henninge et al., Drug Test Anal 2010). FDA's reviewers identify this as the first appearance of the no-DAC form in the literature — a bodybuilding-market product characterised by a doping lab, which is a different provenance from a drug that finished phase 1.

What follows from that: no human pharmacokinetics, no dose-response, no IGF-1 time course, no controlled safety data, and nothing in any professional society guideline. The one thing that is established for the class is that a secretagogue only works through a responsive pituitary — people with complete growth hormone deficiency do not respond to any of these compounds.

The reasoning behind preferring the short-acting form is worth stating properly, because it is the most substantive claim made for it. Endogenous GH is secreted in bursts, largely at night; the DAC version instead produces a sustained elevation lasting days, with GH raised for six days or more after a single injection (Teichman et al., J Clin Endocrinol Metab 2006). Losing the burst pattern is argued to matter because pulse amplitude, not average concentration, is what much of GH's downstream signalling reads.

That argument is coherent and untested for this molecule. What has been shown, in a different compound of the same class, is that a GHRH analogue and a ghrelin-receptor agonist given together drive far more GH than either alone — 24-hour co-infusion of GHRP-2 with GHRH exceeded either agonist by itself in healthy older adults (Bowers et al., J Clin Endocrinol Metab 2004). That synergy is the real basis for pairing a GHRH analogue with a GHRP — it was demonstrated with GHRH and GHRP-2, not with modified GRF 1-29 and ipamorelin.

• Sermorelin — the unmodified parent, GHRH(1-29), which was an FDA-approved product (Geref) before it was discontinued. If you want a GHRH analogue with human data, this is the one that has it.

• CJC-1295 with DAC — the version with the published pharmacology, the terminated phase 2 trial, and the 5.8–8.1 day half-life.

• Tesamorelin — a stabilised GHRH analogue that completed phase 3 and holds an approval.

• Ipamorelin, GHRP-2, GHRP-6 — ghrelin-receptor agonists, a different receptor entirely, which is why they are stacked with GHRH analogues rather than substituted for them.

See also side effects and dosing education.