CJC-1295 DAC: Dosage, Half-Life and Pharmacokinetics
CJC-1295 DAC (with DAC): the long-acting form, its published human pharmacokinetics, and the weekly dosing pattern in circulation.
The short version
CJC-1295 with DAC carries an albumin-binding linker that keeps it in the bloodstream for days. A published human trial reports that single doses of 30 or 60 mcg/kg produced dose-dependent growth hormone and IGF-1 rises lasting up to 28 days. Separately, dosing pages commonly describe a milligram-range weekly protocol. It is a different and much less documented practice than the trial doses, and no regulator has established it.
- The published human trial used single or repeated doses of 30 or 60 mcg/kg, not a milligram-range weekly amount.
- That trial reports an estimated half-life of 5.8-8.1 days for the with-DAC form.
- Dosing pages commonly describe a separate weekly practice of roughly 1-2 mg per injection, once or twice weekly. It is common practice, not trial-established.
- No DAC (mod GRF 1-29) is dosed completely differently, daily rather than weekly. See the no-DAC page.
This page covers CJC-1295 with DAC specifically, the long-acting form, which is dosed on a completely different schedule from the no-DAC form. For the daily no-DAC protocol, see CJC-1295 no DAC. For the full with-DAC/without-DAC distinction, see the main CJC-1295 guide. For the same trial data alongside the site’s dosage calculator, see CJC-1295 dosage.
US legal status - Research use only
CJC-1295 has no FDA-approved product in either form, and no approved indication or dose. Development reached Phase 2 and was discontinued.
AU legal status - Not on the ARTG
Schedule 4 of the Poisons Standard and named under Appendix D - prescription only, and not on the ARTG.
Regulators reach their own conclusions on their own timelines. Where these two disagree, the difference is the point - not an error.
What makes the DAC form different
The Drug Affinity Complex is a chemical addition, an Nε-maleimidopropionyl-lysine group at the C-terminus, that covalently binds circulating albumin. Riding albumin keeps the peptide in the bloodstream for days rather than minutes. That is the reason this form is dosed weekly rather than daily.
CJC-1295 DAC pharmacokinetics: what the trial found
A randomised, placebo-controlled trial in healthy adults aged 21-61 Teichman 2006 - Teichman SL, Neale A, Lawrence B et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805., in the references below tested the with-DAC form specifically. It had two parts:
- A single ascending-dose arm using one of four doses, including 30 or 60 mcg/kg, followed for 28 days.
- A repeat-dose arm giving 30 or 60 mcg/kg as 2-3 subcutaneous injections spaced weekly or every two weeks, followed for 49 days.
The paper reports:
- an estimated half-life of 5.8-8.1 days
- dose-dependent GH increases for 6 or more days after a single injection
- IGF-I increases for 9-11 days after a single injection
- IGF-I kept above baseline for up to 28 days with repeat dosing
It describes 30 and 60 mcg/kg as “relatively well tolerated,” with no serious adverse reactions reported in this small, monitored group of healthy volunteers. This is not a dose this page recommends for anyone else.
CJC-1295 DAC dosage: the weekly practice in circulation
Separate from the trial above, CJC-1295 DAC dosing pages describe a different, milligram-range weekly practice. It is not the mcg/kg trial dose, and no trial or regulator has established it.
- The Peptide Catalog describes a standard research-planning range of roughly 2 mg per injection, once or twice weekly, in 12-16 week cycles with a 6-8 week break. It cites the trial’s own half-life figure as the reason weekly dosing is used at all.
- Peptide Dosing Protocols describes a similar but slightly lower range: 1-2 mg subcutaneously once weekly, or 1 mg split twice weekly. Cycles run 8-12 weeks (extended protocols up to 12-16 weeks) with a 4-6 week break, and a conservative 500-1,000 mcg starting range for the first one to two weeks.
Between the two, the weekly amount in circulation runs roughly 1-2 mg per injection, once or twice a week. Both describe an extended, “advanced” range as high as 2-4 mg weekly. It is less consistently repeated and is not treated here as the common figure.
For reconstitution and injection-volume arithmetic, the dosage calculator does that conversion. It does not choose a dose.
Who should not use it, and side effects
No FDA-reviewed contraindication list exists, because no such review has happened. The published trial excluded people with clinically significant medical conditions, recent illness and pregnancy. That shows who a monitored study considered eligible, not a safety clearance for anyone else.
At the doses it tested, the trial reported no serious adverse reactions. That says nothing about the much-higher milligram-range weekly practice in wider circulation, for which no comparable human safety data exists at all.
FDA states that it has identified serious adverse events associated with CJC-1295. They include increased heart rate and a systemic vasodilatory reaction (blood vessels widening throughout the body). FDA also says available clinical data are limited, and that compounded versions may pose a risk of an immune reaction to the drug for certain routes of administration. FDA does not say how often these events occurred. Full detail: CJC-1295 side effects.
Related
- CJC-1295 no DAC dosage - the short-acting, daily-dosed form
- CJC-1295: with DAC and without DAC, explained
- CJC-1295 dosage (trial data and calculator)
- Dosage calculator
Common questions
What is CJC-1295 with DAC?
It is CJC-1295 carrying a Drug Affinity Complex, an added chemical group that covalently binds circulating albumin. That keeps the peptide in the bloodstream for days rather than minutes. A published human pharmacokinetic study reports an estimated half-life of 5.8-8.1 days for this form.
What dose did the published CJC-1295 DAC trial use?
A randomized, placebo-controlled trial in healthy adults gave subcutaneous doses of 30 or 60 micrograms per kilogram of body weight. Participants received either a single ascending dose (followed for 28 days) or 2-3 repeated doses spaced weekly or every two weeks (followed for 49 days). That is a trial design and dose reported in a peer-reviewed paper, not a recommended dose for anyone outside it.
What is the common CJC-1295 DAC dosing pattern outside the trial?
Dosing pages describe a milligram-range weekly practice, commonly around 1-2 mg per injection, once or twice weekly. That figure is common practice reported by dosing-guide pages. It is not the dose the published trial used, and no trial or regulator has established it.
How long does CJC-1295 DAC last?
The published trial reports an estimated half-life of 5.8-8.1 days. A single injection produced GH increases for 6 or more days and IGF-1 increases for 9-11 days. Repeat dosing kept IGF-1 above baseline for up to 28 days.
Is CJC-1295 DAC different from no-DAC?
Yes. The DAC form has published human pharmacokinetic data and is dosed roughly weekly by common practice. The no-DAC form (mod GRF 1-29) has no published human pharmacokinetic study and is dosed daily by common practice. See the no-DAC page for that separate protocol.
References (4 sources)
Bibliographic detail is fetched from PubMed, not written by me - so a citation here cannot drift from the paper it names. Study design comes from PubMed's own tags rather than my judgement.
- 1.Teichman SL, Neale A, Lawrence B et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805.Randomised trialPMID 16352683
- 2.FDA - Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks (content current as of 22 April 2026). Its CJC-1295 entry states that FDA has identified serious adverse events including increased heart rate and systemic vasodilatory reaction, that available clinical data are limited, and that compounded versions may pose a risk of immunogenicity for certain routes of administration.- US Food and Drug Administrationregulatory
- 3.The Peptide Catalog- thepeptidecatalog.comother
- 4.Peptide Dosing Protocols- peptidedosingprotocols.comother