CJC-1295
| Category | Growth Hormone Secretagogues |
| Goals | Muscle & Performance · Recovery · Sleep |
| Evidence level | Preclinical for body-composition claims (single human PK/dose study; no efficacy RCTs) |
| Legal status | Research-only — not approved for human use |
| FDA status | Not approved; pharmaceutical development discontinued |
| Half-life | DAC version ~6–8 days; no-DAC (“Mod GRF 1-29”) ~30 min |
| Routes | Subcutaneous · Intramuscular |
| CAS / MW / Sequence | 446262-90-4 (DAC) · ~3647 g/mol · modified GHRH(1-29) tetrasubstituted analog |
| Last reviewed | 2026-06-05 |
In one line
A long-acting synthetic analog of growth-hormone-releasing hormone (GHRH) designed to raise GH and IGF-1; it exists as a long-acting DAC version and a short-acting no-DAC version (“Mod GRF 1-29”), and is most often paired with a GHRP like Ipamorelin.
Evidence at a glance
Human data is limited to early-phase pharmacokinetic/dose studies showing CJC-1295 raises GH and IGF-1. There are no published trials demonstrating muscle, fat-loss, or performance benefits in humans, and the drug’s clinical development was discontinued. See Evidence Grading Explained and the Disclaimer.
Key Takeaways
- A GHRH analog: it stimulates the pituitary’s own GH-releasing pathway, producing GH/IGF-1 elevation rather than supplying GH directly.
- Two forms are sold: CJC-1295 with DAC (Drug Affinity Complex; binds albumin, half-life ~6–8 days) and CJC-1295 without DAC = Modified GRF 1-29 (half-life ~30 min, dosed multiple times daily).
- The DAC version produces a sustained (“bleed”) rise in GH; the no-DAC version preserves more pulsatile GH release, which is why bodybuilding protocols favor it with a GHRP.
- Human evidence = PK and GH/IGF-1 elevation only; no efficacy outcomes. Not FDA-approved; development was halted.
- Most commonly stacked with Ipamorelin — see CJC-1295 + Ipamorelin.
What Is It
CJC-1295 is a synthetic analog of GHRH(1-29) — the bioactive N-terminal fragment of human growth-hormone-releasing hormone. It carries four amino-acid substitutions (commonly at positions 2, 8, 15, 27) that protect it from enzymatic breakdown, giving the base molecule a longer life than native GHRH.
The “with DAC” version adds a Drug Affinity Complex (a maleimidoproprionic acid / lysine linker) that binds covalently to circulating albumin, turning the peptide into a slow-release depot that acts for days. The “without DAC” version — widely sold as Modified GRF 1-29 (Mod GRF 1-29 / CJC-1295 no-DAC) — lacks that linker and clears within roughly half an hour. The two are pharmacologically very different despite sharing the “CJC-1295” name.
Mechanism of Action
- GHRH-receptor agonism (established mechanism) — binds the pituitary GHRH receptor on somatotrophs, stimulating synthesis and pulsatile release of endogenous GH, which in turn drives hepatic IGF-1 production.
- Albumin binding via DAC (human PK data) — the DAC moiety attaches to albumin, extending half-life to ~6–8 days and producing sustained GH/IGF-1 elevation.
- Pulse-preserving (no-DAC) (rationale) — Mod GRF 1-29’s short action is intended to amplify a natural GH pulse, which is why it is timed with a GHRP (ghrelin-receptor agonist) that triggers a pulse through a complementary pathway.
DAC vs no-DAC matters
A continuous DAC-driven rise can blunt the natural pulsatile pattern of GH secretion, which some researchers consider less physiological. The short-acting no-DAC form is preferred in synergy protocols for this reason. See Half-Life & Pharmacokinetics.
Evidence by Outcome
| Outcome | Evidence | Notes |
|---|---|---|
| Raises GH / IGF-1 | Clinical | Teichman 2006 (JCEM): single SC dose raised GH 2–10× and IGF-1 1.5–3× for days |
| Sustained IGF-1 elevation | Clinical | IGF-1 above baseline up to ~28 days after repeated DAC dosing |
| Muscle / lean-mass gain | Anecdotal | No human efficacy trials; extrapolated from GH/IGF-1 biology |
| Fat loss / body recomposition | Anecdotal | No controlled human data |
| Sleep / recovery | Anecdotal | Plausible via GH physiology; not directly studied for CJC-1295 |
Reported Dosing
Not medical advice
Protocols as reported in community sources and non-clinical literature. There is no established human therapeutic dose. See Reconstitution & Dosing Math.
| Form | Dose (reported) | Frequency | Notes |
|---|---|---|---|
| DAC | ~1–2 mg/week (often split) | 1–2× weekly | Long half-life; sustained IGF-1 |
| No-DAC (Mod GRF 1-29) | ~100 µg per dose | 1–3× daily, often pre-sleep | Timed with a GHRP; empty-stomach commonly described |
| With GHRP combo | ~100 µg no-DAC + 100–300 µg Ipamorelin | per dose | The standard community pairing |
Pharmacokinetics
The DAC version’s defining feature is its ~6–8 day half-life (estimated 5.8–8.1 days in the Teichman 2006 study), enabling weekly dosing and a sustained GH/IGF-1 plateau. The no-DAC form (Mod GRF 1-29) clears within ~30 minutes, producing a brief GH pulse and requiring multiple daily doses. Both are peptides destroyed in the gut, so dosing is injectable (subcutaneous). See Half-Life & Pharmacokinetics.
Side Effects & Risks
- Water retention, tingling/flushing, head-rush, and injection-site reactions are commonly reported — consistent with GHRH/GH effects.
- Sustained DAC elevation of GH/IGF-1 is the main theoretical concern: chronically high IGF-1 carries speculative links to insulin resistance and, in general GH literature, concerns about tissue overgrowth; not characterized for CJC-1295 specifically.
- A purported “CJC-1295 with DAC” lot tied to safety concerns in early development underscores that long-term human safety is unestablished.
- Sourcing risk: as a research chemical, DAC vs no-DAC identity and purity vary widely — verify before trusting a product. See Sourcing, Red Flags & Scams, Bloodwork & Monitoring, Side Effects & Risk Management.
Cycling
Community protocols often run CJC-1295 (usually no-DAC + GHRP) in 8–12 week blocks with breaks, partly to limit receptor desensitization and monitor IGF-1. No evidence-based cycling standard exists. See Cycling.
Stacks It Appears In
- CJC-1295 + Ipamorelin — the canonical GHRH + GHRP pairing (usually no-DAC CJC-1295)
- Sometimes combined with MK-677 or used alongside Sermorelin/Tesamorelin discussions as GHRH-class alternatives
Comparisons
- Sermorelin vs CJC-1295 — Sermorelin is GHRH(1-29) without the stabilizing substitutions; much shorter-acting.
- vs Tesamorelin — Tesamorelin is an FDA-approved GHRH analog (for HIV lipodystrophy); CJC-1295 is not approved.
- vs Ipamorelin / Hexarelin — those are GHRPs (ghrelin-receptor agonists), a complementary mechanism rather than GHRH.
Sourcing & Quality
Sold as a lyophilized “research chemical,” and the DAC vs no-DAC distinction is frequently mislabeled, so identity and purity are not guaranteed. Evaluate quality before trusting a product: How to Read a CoA, Sourcing, Red Flags & Scams. Reconstitution and storage: Reconstitution & Dosing Math, Storage & Handling. No vendors are endorsed here.
Legal & Regulatory Status
(As of 2026-06-05.) Not FDA-approved for human use; pharmaceutical development was discontinued and it remains an unapproved investigational substance sold only as a research chemical. GH secretagogues are prohibited in and out of competition under the WADA Prohibited List (Section S2). Status varies by country. See Regulatory & Legal Status.
FAQ
What’s the difference between CJC-1295 with DAC and without DAC? The DAC version binds albumin for a ~6–8 day half-life and weekly dosing; the no-DAC version (“Mod GRF 1-29”) lasts ~30 minutes and is dosed multiple times daily, usually with a GHRP.
Is CJC-1295 FDA-approved? No. It is unapproved and its clinical development was halted.
Does it build muscle in humans? Human studies only show it raises GH and IGF-1. There are no trials demonstrating muscle, strength, or fat-loss benefits.
Why pair it with Ipamorelin? GHRH (CJC-1295) and a GHRP/ghrelin agonist (Ipamorelin) act through complementary pathways and together produce a larger GH pulse — see CJC-1295 + Ipamorelin.
References
- Teichman S.L. et al. (2006). “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.” Journal of Clinical Endocrinology & Metabolism, 91(3):799–805.
- Ionescu M., Frohman L.A. (2006). “Pulsatile secretion of GH persists during continuous stimulation by CJC-1295, a long-acting GHRH analog.” J Clin Endocrinol Metab, 91(12):4792–4797.
- Sackmann-Sala L., Ding J., Frohman L.A., Kopchick J.J. (2009). Review of GHRH analogs including CJC-1295.
- U.S. FDA (2024–2026). Bulk drug substance docket materials referencing CJC-1295 (with/without DAC).
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