The doses that appear in the literature.

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This page describes the doses, intervals, routes, and durations that appear in the published CJC-1295 research literature. It is not a recommendation. It does not constitute a dosing schedule for human use. CJC-1295 is not approved for any human indication and is not legally prescribable in the United States ^[14][15].

The doses below were administered in formal clinical trials or preclinical studies under research protocols. They are reported here for completeness — because the question “what doses were studied?” is a recurring one in the research literature, and because every claim about half-life, GH elevation, IGF-1 elevation, and adverse events on this site traces back to a specific dose given in a specific study.

The dosing unit µg/kg means micrograms per kilogram of body weight. Most published CJC-1295 dosing is expressed in those units. Subcutaneous (SC) is the predominant route across all reviewed human and animal studies. A small amount of preclinical work used the intraperitoneal route in rodents; some foundational comparator work with native GHRH used intravenous administration.

The Phase 1 dose-ranging cohorts

The central dose-ranging data in the CJC-1295 human literature come from Teichman and colleagues in 2006 ^[2][3].

Four single-dose cohorts received subcutaneous injections at:

• 30 µg/kg
• 60 µg/kg
• 125 µg/kg
• 250 µg/kg

Each cohort comprised approximately eleven healthy adults aged 21 to 61, with placebo controls. The cohorts were studied to characterize dose-dependent pharmacodynamics and pharmacokinetics. Across the four dose levels, mean plasma GH rose two- to tenfold in a dose-dependent pattern and remained elevated for at least six days. Mean IGF-1 rose 1.5 to 3-fold and remained elevated for nine to eleven days ^[2].

Multiple-dose cohorts in the same Phase 1 program received weekly or biweekly subcutaneous injections over study durations of twenty-eight to forty-nine days. In those cohorts, IGF-1 elevation was sustained for up to twenty-eight days. The dose-ranging strategy was incremental — characterizing the response at each step rather than pushing to a maximum tolerated dose ^[2].

Adverse events at the lower dose levels (30 and 60 µg/kg) were predominantly local — injection-site pain, swelling, and induration. Systemic adverse events were uncommon at those levels. The published data did not establish a dose-limiting toxicity in the cohorts studied ^[18].

The Phase 2 regimen, with caveats

The ClinicalTrials.gov record for NCT00267527 indicates a weekly subcutaneous dosing regimen for the Phase 2 study of CJC-1295 in HIV-associated visceral obesity ^[7]. The full µg/kg specification was not published before the trial was terminated in October 2006 after a participant death judged unrelated to study drug. The Phase 2 dosing protocol cannot be reported here in full because it was never released in peer-reviewed form.

Preclinical doses: the knockout mouse

The preclinical rescue study by Alba and colleagues in GHRH-knockout mice used 2 µg per injection at intervals of 24, 48, or 72 hours, sustained over five weeks ^[5]. In a 25 g mouse, 2 µg corresponds to roughly 80 µg/kg per injection.

The study found that once-daily dosing normalized body length, body weight, and lean composition to wild-type levels. Forty-eight- and seventy-two-hour intervals produced partial restoration of growth parameters. Pituitary somatotroph proliferation and GH mRNA expression increased across all dosing intervals.

The Jetté discovery paper in rats used dose-ranging subcutaneous bolus administration at low µg/kg levels to characterize the bioconjugate pharmacokinetics. Specific cohort doses were reported in the original paper ^[1].

Half-life: the central pharmacokinetic fact

The defining pharmacokinetic parameter for CJC-1295 is its mean plasma half-life in healthy adult humans: 5.8 to 8.1 days across dose cohorts, as estimated in the Teichman Phase 1 ^[3]. The wide range reflects between-cohort variability and the limits of resolution in a multi-day PK study.

The mechanism for that extended half-life is the covalent bioconjugation to serum albumin at cysteine 34 via the C-terminal maleimide linker. Albumin’s slow turnover — measured in days, not hours — becomes the rate-limiting step for clearance of the bound peptide. That mechanism is the only reason CJC-1295 carries a multi-day half-life. The non-DAC variant of the modified GRF(1-29) backbone — sometimes labeled “CJC-1295 without DAC” in non-peer-reviewed sources — has a plasma half-life of approximately thirty minutes, because it lacks the albumin tether ^[8].

Routes and stability

Subcutaneous administration is the predominant route across all reviewed human and animal studies. Intraperitoneal administration appears in some rodent mechanism work. Intravenous administration is limited to foundational comparator work with native GHRH (notably the Bowers 1990 synergy study, where GHRH and GHRP-6 were administered IV at 1 µg/kg each ^[9]).

The DAC bioactivity depends on the covalent attachment to albumin’s Cys34 thiol forming after injection. Reconstituted research peptide is typically stored refrigerated for short-term laboratory use and frozen for longer-term storage. Freeze-thaw cycles and elevated temperatures degrade activity. The non-DAC variant degrades faster because it lacks the albumin tether and is more susceptible to plasma clearance.

These stability considerations are reported in the analytical chemistry literature on peptide identification and detection ^[11][12] and in research-grade handling literature. They are not a substitute for pharmaceutical-grade quality control, which does not exist for CJC-1295 because no manufacturer has carried it through a regulatory approval process.

What the literature does not establish

Several questions about CJC-1295 dosing have not been answered in the published research:

Long-term human safety. The published Phase 1 program covered short-duration exposure in healthy adults. No long-term human safety RCT exists for CJC-1295.

Dose-response for clinical endpoints. The published human data establish dose-response for GH and IGF-1 biomarkers. They do not establish dose-response for body composition, metabolic, or any other clinical endpoint in patients, because the Phase 2 program did not complete.

Optimal dosing interval. The mouse-rescue data support less-than-daily dosing as feasible given the multi-day half-life ^[5]. The optimal interval for any human indication has not been established because no Phase 2 or 3 program reached publication.

Combination dosing. The CJC-1295 plus ipamorelin combination widely discussed in research-peptide literature is grounded in the 1990 Bowers GHRH-plus-GHRP synergy paper ^[9]. It has not been characterized in a peer-reviewed clinical trial.