CJC-1295 DAC: Dosing Protocols

Research Dosing Disclaimer#

CJC-1295 DAC is an investigational compound that has not been approved for clinical use by the FDA or any other regulatory agency. The dosing information below is derived from published clinical trial protocols and is provided for educational and research reference purposes only. This information does not constitute medical advice or prescribing guidance.

Clinical Trial Dosing Protocols#

Single-Dose Pharmacokinetic Studies#

In the pivotal clinical study by Teichman et al. (2006), CJC-1295 DAC was administered as a single subcutaneous injection at doses ranging from 30 to 120 micrograms per kilogram of body weight. This weight-based dosing approach was used to standardize drug exposure across subjects of different body sizes.

At the lowest dose studied (30 mcg/kg), significant increases in both GH and IGF-1 were observed, with IGF-1 elevation persisting for approximately 6 days. At the highest dose (120 mcg/kg), GH concentrations were elevated up to 10-fold above baseline, and IGF-1 remained elevated for up to 14 days.

Multiple-Dose Studies#

For the multiple-dose phase, weekly subcutaneous injections at 30 to 60 mcg/kg were administered for 4 to 8 weeks. This weekly dosing schedule was selected based on the pharmacokinetic half-life of 6 to 8 days, which allows for sustained receptor activation throughout the dosing interval while avoiding excessive accumulation.

The multiple-dose data showed progressive elevation of IGF-1 levels over the first 2 to 4 weeks, followed by a plateau as steady state was approached. This accumulation pattern is consistent with the predicted pharmacokinetics based on the albumin-conjugated half-life.

Dose Selection Rationale#

The clinical trial dose range of 30 to 120 mcg/kg was selected based on preclinical pharmacokinetic and pharmacodynamic modeling. For a 75 kg individual, this translates to approximately 2.25 to 9 mg per dose. The lower end of this range (30 mcg/kg, approximately 2 to 2.5 mg for a typical adult) produced clinically meaningful IGF-1 elevation while maintaining a favorable safety profile.

Pharmacokinetic Considerations#

The extended half-life of CJC-1295 DAC fundamentally distinguishes its dosing requirements from those of shorter-acting GHRH analogs. The key pharmacokinetic parameters relevant to dosing include a plasma half-life of approximately 6 to 8 days (after albumin conjugation), time to peak IGF-1 of approximately 48 to 96 hours after injection, duration of IGF-1 elevation of 6 to 14 days (dose-dependent), and steady-state achievement after approximately 2 to 3 weekly doses.

The long half-life has important implications for dosing. First, weekly dosing is sufficient to maintain continuous pharmacodynamic effects, unlike shorter-acting GHRH analogs that require daily or multiple daily injections. Second, there is meaningful accumulation with repeated dosing, meaning that steady-state plasma levels are approximately 2 to 3 times higher than after a single dose. Third, after discontinuation, the pharmacological effects persist for 1 to 2 weeks due to the slow clearance of the albumin conjugate.

Administration Technique#

Subcutaneous Injection#

All clinical trials of CJC-1295 DAC have used subcutaneous administration. The injection is performed using standard subcutaneous injection technique: a 27- to 30-gauge, 0.5-inch needle inserted at a 45-degree angle into a pinched fold of skin. The injection volume is typically 0.1 to 0.5 mL depending on the reconstitution concentration and dose.

Recommended injection sites include the abdomen (at least 2 inches from the navel), the anterior thigh, and the upper arm. Rotation of injection sites is recommended to minimize the risk of local tissue reactions.

Timing of Administration#

The clinical trials did not specify a particular time of day for injection. However, because CJC-1295 DAC amplifies endogenous GH secretion, including the large nocturnal GH pulses, some researchers have suggested that evening administration may be advantageous for maximizing the synergy with natural GH release patterns. This hypothesis has not been formally tested in clinical studies.

Reconstitution Instructions#

CJC-1295 DAC is typically supplied as a lyophilized powder in sealed vials. Reconstitution should be performed under clean conditions using bacteriostatic water (containing 0.9% benzyl alcohol as preservative) or sterile water for injection.

For reconstitution, first allow the vial to reach room temperature. Clean the vial stopper with an alcohol swab. Slowly inject the bacteriostatic water into the vial, directing the stream against the glass wall rather than directly onto the lyophilized cake. Allow the peptide to dissolve by gentle swirling; do not shake or agitate vigorously, as this can cause protein denaturation and foaming. Once fully dissolved, the solution should be clear and colorless.

Storage and Stability#

Lyophilized CJC-1295 DAC should be stored at -20 degrees Celsius or colder. At this temperature, the powder is stable for extended periods. The reconstituted solution should be stored refrigerated at 2 to 8 degrees Celsius and used within approximately 3 weeks. The reconstituted solution should not be frozen, as freeze-thaw cycles can damage the peptide and reduce the reactivity of the maleimide group in the DAC moiety.

The maleimide component of the DAC is susceptible to hydrolysis in aqueous solution, which can reduce the albumin-binding efficiency over time. This hydrolysis is accelerated at higher temperatures and pH values. Therefore, prompt use of reconstituted material and proper refrigerated storage are important for maintaining the full pharmacological activity of the compound.

Related Reading#

• CJC-1295 DAC overview and research guide
• CJC-1295 DAC side effects profile
• CJC-1295 DAC research evidence