CJC-1295 DAC vs no DAC: meaning and half-life
An albumin-binding modification separates the long-acting research compound from the short-acting form commonly given its name.
No DAC meaning
“No DAC” means the albumin-binding Drug Affinity Complex modification is absent. The short-acting peptide is commonly called Modified GRF (1-29), also written Mod GRF 1-29. The albumin-conjugation study in rats explains the modification absent from this form. It retains the four stabilising substitutions in the GHRH fragment.
I take the naming problem seriously because it changes which experiment a claim can cite. The long-acting human results were obtained with the albumin-conjugating compound. A sentence about “CJC-1295” that leaves the form unnamed conceals an essential part of the comparison.
DAC vs no DAC at a glance
| Feature | CJC-1295 DAC | No DAC / Modified GRF (1-29) |
|---|---|---|
| Albumin-binding handle | Present | Absent |
| Duration | Estimated half-life 5.8-8.1 days in healthy adults | Short-acting, minutes to hours |
| Shared design | Four stabilising substitutions on hGRF(1-29) | Four stabilising substitutions on hGRF(1-29) |
| Human-use approval | Unapproved | Unapproved |
The human DAC study supplies the 5.8-8.1-day estimate. The Modified GRF entry in the reference list describes the form without the albumin-binding moiety. “Minutes to hours” is the broad description available here for no DAC.
How DAC attaches to albumin
DAC stands for Drug Affinity Complex. A maleimidopropionyl handle on a terminal lysine reacts with the free thiol at Cys34 on serum albumin. The result is a covalent peptide-albumin conjugate. Jette and colleagues demonstrated the albumin-binding approach in rats, where growth-hormone exposure increased and peptide remained detectable beyond 72 hours.
The four substitutions address enzymatic breakdown; the albumin attachment extends residence in circulation. Those are distinct design changes. The half-life discussion follows the human duration measurements without assigning them to the short-acting form.
CJC 1295 no DAC half life
The phrase “CJC 1295 no DAC half life” often leads to the DAC number. In the record used here, the no-DAC form is short-acting, described in the minutes-to-hours range. The 5.8-8.1-day estimate comes from healthy adults given the long-acting DAC compound.
That leaves an asymmetry in the evidence: a numerical human estimate for DAC, a broad short-duration description for no DAC. I favour the unevenly specified evidence over a precise-looking number that this source set cannot justify.
No-DAC dosage searches
A search such as “cjc ko dac dosages” can land in the same naming confusion. The published study doses describe the administrations that generated the long-acting human data. They cannot establish a no-DAC regimen or a CJC-1295/ipamorelin regimen.
Neither form has a validated human dose in this record. The published DAC study identifies its own experimental conditions. Legitimacy for a dose claim would require evidence for the named compound, population and outcome; swapping the name while retaining a number loses those conditions.