CJC-1295 (with and without DAC) Half-Life & Pharmacokinetics — Research Guide (2026)

Research-use only. This guide summarises published pharmacokinetic (PK) data on CJC-1295 (with and without DAC) for laboratory research and educational reference. Nothing on this page is medical advice or a recommendation for human use.

CJC-1295 (with and without DAC) is classified as a GHRH analogue; with-DAC variant uses Drug Affinity Complex technology. Its pharmacokinetic profile — serum half-life, time to peak (Tmax), route-of-administration behaviour, clearance pathway and bioavailability — directly shapes how researchers schedule dosing, interpret PD endpoints and design steady-state experiments.

At-a-Glance Pharmacokinetics

| Parameter | CJC-1295 | | --- | --- | | Classification | GHRH analogue; with-DAC variant uses Drug Affinity Complex technology | | Serum half-life | Without DAC (Mod GRF 1-29): ~30 minutes. | | Tmax | No-DAC: ~15 minutes. | | Validated routes | Subcutaneous administration is standard in the published literature for both DAC and no-DAC variants. | | Bioavailability | Subcutaneous bioavailability ~50–70% (no-DAC) and >80% (DAC) in published PK datasets. | | Clearance | No-DAC: rapid enzymatic clearance. |

Serum Half-Life

Without DAC (Mod GRF 1-29): ~30 minutes. With DAC (albumin-bound): published terminal half-life of ~6–8 days, supporting weekly dosing in research protocols.

The functional implication is that steady-state PK is reached at approximately 4–5 half-lives. For CJC-1295, that informs how quickly researchers can expect plasma exposure to stabilise across repeat dosing.

Time to Peak (Tmax)

No-DAC: ~15 minutes. With DAC: serum GH and IGF-1 elevations persist for 6–8 days post-dose in published clinical PK studies.

Tmax is the parameter that most directly governs acute pharmacodynamic readouts. For GH-axis peptides this dictates blood-sampling timing for stimulated GH; for incretin analogues it shapes the post-prandial glucose challenge window.

Routes of Administration

Subcutaneous administration is standard in the published literature for both DAC and no-DAC variants.

Bioavailability across routes: Subcutaneous bioavailability ~50–70% (no-DAC) and >80% (DAC) in published PK datasets.

Clearance & Metabolism

No-DAC: rapid enzymatic clearance. With-DAC: albumin binding extends circulation; cleared via normal albumin turnover and renal handling of fragments.

Key Pharmacokinetic Takeaways

• Two distinct pharmacokinetic profiles depending on the DAC linker — never substitute one for the other
• DAC variant produces sustained 'GH bleed' rather than pulsatile release; no-DAC preserves pulsatility
• Weekly dosing of DAC variants is supported by the 6–8 day terminal half-life in published human PK
• Frequently stacked with ipamorelin in pulsatile-stimulation research protocols

Frequently Asked Questions

What is the half-life of CJC-1295? Without DAC (Mod GRF 1-29): ~30 minutes. With DAC (albumin-bound): published terminal half-life of ~6–8 days, supporting weekly dosing in research protocols.

How quickly does CJC-1295 reach peak concentration? No-DAC: ~15 minutes. With DAC: serum GH and IGF-1 elevations persist for 6–8 days post-dose in published clinical PK studies.

Which routes of administration are validated in published research? Subcutaneous administration is standard in the published literature for both DAC and no-DAC variants.

Does CJC-1295 accumulate with repeat dosing? No-DAC: rapid enzymatic clearance. With-DAC: albumin binding extends circulation; cleared via normal albumin turnover and renal handling of fragments. Steady-state is typically reached at 4–5 half-lives in published multi-dose studies.

Is oral bioavailability meaningful for CJC-1295? Subcutaneous bioavailability ~50–70% (no-DAC) and >80% (DAC) in published PK datasets.

Related Research

• Reconstitution & storage protocols — see the CJC-1295 reconstitution guide for vial handling that preserves the PK profile described above.
• Dosing protocols research — see the CJC-1295 dosing protocols article for how PK parameters translate into scheduling decisions.
• Mechanism of action — see the CJC-1295 mechanism guide for the receptor-level basis of the PD effects driven by the PK profile.

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*Sources cited inline are drawn from published preclinical and clinical pharmacokinetic literature. This article is for laboratory research and educational use only and does not constitute medical advice.*