Short answer: DAC (drug affinity complex) lets CJC-1295 bind albumin in the blood, which stretches its half-life to 5.8 to 8.1 days in healthy adults.1 CJC-1295 without DAC, also called Mod GRF 1-29, has no published human half-life or clinical data. Neither is FDA approved.
| CJC-1295 with DAC | CJC-1295 without DAC (Mod GRF 1-29) | |
|---|---|---|
| Mechanism | GHRH analog bound to albumin through the DAC linker | Modified GHRH 1-29 without the albumin-binding linker |
| Approval status | Not FDA approved | Not FDA approved |
| Dosing in studies | Single and repeated doses of 30 to 250 mcg/kg under the skin in healthy adults1 | No published human studies |
| Half-life | 5.8 to 8.1 days1 | No published human value |
| Effect duration reported | GH up 2- to 10-fold for 6 days or more; IGF-1 up 1.5- to 3-fold for 9 to 11 days after one dose1 | Not studied in humans |
| GH pulses | Pulsatile GH release persisted during stimulation2 | Not studied in humans |
| Dosing frequency | Weekly or less often in the studies | Not established |
| Typical vial sizes | 2 or 5 mg powder | 2 or 5 mg powder |
| Notable warnings | No label. Prohibited in sport (WADA) | No label. Prohibited in sport (WADA) |
Native GHRH is broken down within minutes. The DAC is a chemical linker that lets the peptide attach to albumin, the most common protein in blood, which protects it and keeps it circulating. In the 2006 study, that turned a minutes-long signal into one lasting about a week.1 A follow-up study found the body still released GH in pulses rather than one continuous flat level.2
Very little in humans. It is the same modified GHRH 1-29 sequence without the albumin-binding linker, so it is expected to be short-acting, but no published study has measured its half-life or effects in people. Figures quoted online are not from human pharmacokinetic studies.