CJC-1295 with DAC

8/10 · Human trials: PK/PD biomarkers, not recovery efficacy

Compound Profile

Overview

CJC-1295 with DAC is a long-acting analogue of growth-hormone-releasing hormone (GHRH). DAC stands for drug affinity complex: its albumin-binding modification extends exposure and distinguishes the clinical agent from substances marketed as “CJC-1295 no DAC”. FDA’s technical review treats DAC and non-DAC substances as different active moieties and also distinguishes their salt forms. [1–3]

The principal human studies examined endocrine pharmacology in healthy adults. Teichman reported placebo-controlled trials lasting 28 and 49 days, with sustained GH and IGF-I increases and an estimated half-life of 5.8–8.1 days. Ionescu and Frohman found that GH pulsatility persisted one week after administration, while trough and mean hormone concentrations increased. Preclinical work had established the albumin-binding and pituitary-signalling rationale. [1,2,4]

These findings make DAC relevant to prolonged GH/IGF-I stimulation research. Clinical injury recovery and longevity outcomes have not been evaluated in the cited trials; the early short-term safety observations are supplemented by FDA concerns about increased heart rate and systemic vasodilatory reactions. [1–3,5]

Effects

• Single SC exposure: mean GH increased 2–10-fold for at least 6 days across studied doses. [1] [human randomised PK/PD trials]
• Single SC exposure: mean IGF-I increased 1.5–3-fold for 9–11 days; repeat-dose IGF-I remained above baseline through day 28. [1,3] [human randomised PK/PD trials]
• Single-dose half-life 5.8–8.1 days; repeated exposure showed accumulation under the study schedules. [1,3] [human pharmacokinetic trials]
• Pulse study: trough GH +7.5-fold, mean GH +46% and IGF-I +45% one week after 60 or 90 µg/kg. [2] [human physiological study]
• GH pulse frequency and magnitude were unchanged in that study; prolonged exposure is not equivalent to complete loss of pulsatility. [2] [human physiological study]
• The studied hormone changes were not measurements of tendon healing, strength gain, sleep quality, fat loss or longevity. [1,2] [endpoint limitation]

Mechanism of Action

GHRH stimulates GH secretion from the anterior pituitary. CJC-1295 combines a modified GHRH analogue with an albumin-reactive group that attaches to albumin’s free thiol at Cys34. In the original preclinical work, the conjugate retained activity in cultured rat pituitary cells, resisted dipeptidylpeptidase-IV degradation more effectively in vitro and produced prolonged GH exposure in rats. Albumin association provides the rationale for the multi-day exposure subsequently measured in humans. [1,4]

Pituitary GH release stimulates the GH/IGF-I axis, with response depending on preserved pituitary secretory capacity. In Ionescu/Frohman, a single 60 or 90 µg/kg dose increased trough GH 7.5-fold, mean GH 46% and IGF-I 45% at one week; pulse frequency and magnitude remained unchanged. Sustained hormone exposure can therefore coexist with continuing pulses rather than larger or more frequent pulses. [2]

Human pharmacokinetics and endocrine response

Teichman’s two randomised, double-blind, placebo-controlled studies followed healthy adults aged 21–61 for 28 and 49 days. Single-dose cohorts received 30, 60, 125 or 250 µg/kg SC. Across studied exposures, mean GH increased 2–10-fold for at least six days and mean IGF-I 1.5–3-fold for 9–11 days; estimated half-life was 5.8–8.1 days. [1,3]

Study 2 had four six-person cohorts, each with five active and one placebo participant: 30 or 60 µg/kg on days 0 and 14, or 30 or 20 µg/kg on days 0, 7 and 14. Repeated exposure produced cumulative endocrine effects, with IGF-I elevation through day 28. The dosing table preserves these separate arms. [1,3]

GH pulsatility

Ionescu/Frohman studied healthy men aged 20–40 after a single 60 or 90 µg/kg dose. Sampling every 20 minutes over 12 hours before dosing and one week later showed a 7.5-fold rise in trough GH, a 46% rise in mean GH and a 45% rise in IGF-I, with unchanged pulse frequency and magnitude. The measured result is prolonged exposure with persistent pulsatility. [2]

Injury recovery and musculoskeletal outcomes

Not clinically evaluated. The cited human DAC studies measured hormone exposure and secretion patterns, not tendon, ligament, muscle or nerve-injury healing. Musculoskeletal recovery remains a separate clinical research question. [1,2]

Anti-aging and longevity

Interest arises from age-related changes in the GH axis. The cited DAC trials assessed hormone responses rather than longevity, frailty or validated biological-age outcomes. [1,2]

Combination protocols

The practitioner educational attachment separately describes DAC 600 µg once weekly and a CJC-1295 w/o DAC–ipamorelin bedtime mixture. The latter contains 1 mg/mL of each ingredient and uses 0.05–0.1 mL (50–100 µg each) five days weekly. These are distinct formulations and educational dosing descriptions; the controlled DAC studies tested neither combination recovery efficacy nor mixture compatibility. [1,2,7]

Exploratory serum-protein biomarkers

Sackmann-Sala examined sera from 11 healthy young adult men before exposure and one week later. Selected protein spots changed, including apolipoprotein A1, transthyretin and albumin-related fragments. This was exploratory serum-biomarker work. [8]

Human research exposures — separate cohorts

Study 2 has five active participants and one placebo per arm. Cumulative amounts for cohorts 1–4 were 60 / 120 / 90 / 60 µg/kg; these are totals, not durations or loading/maintenance stages. The 28-/49-day study programmes are observation periods, not established treatment cycles. Ionescu sampled for 12 hours every 20 minutes at each assessment; sampling duration is not a dosing cycle. [1–3]

Biohacking & Off-Label Use

CJC-1295 DAC attracts interest because it extends a GHRH-like signal and changes circulating GH/IGF-I. Its multi-day exposure distinguishes it from shorter-acting GHRH analogues and makes the DAC identity important when discussing endocrine interventions.

For the related recovery topic, see Regenerative Recovery. The cited DAC trials concern hormone exposure rather than clinical injury healing.

Practitioner educational description, separate from clinical research

A practitioner educational attachment hosted in FDA docket FDA-2024-N-4777-0002 explicitly lists CJC 1295 w/DAC: 600 µg once weekly, with a suggested 2–3-hour interval after the last meal. It does not specify a cycle length or report a controlled recovery outcome. The same document explicitly labels its CJC/ipamorelin bedtime mixture w/o DAC. This is evidence of how that author describes practice, not an FDA recommendation, a proven fasting requirement or a validated recovery regimen. [7]

The document also makes broader benefit and “GH-bleed” claims. Those are not adopted here: the primary human pulse study observed preserved pulses with increased trough GH. [2]

Routes of Administration

Subcutaneous — route in the human DAC studies

The cited healthy-adult DAC studies used subcutaneous administration of the investigational long-acting compound. Their pharmacokinetic and endocrine findings apply to that route and clinical agent. [1,2]

Oral / intranasal / alternative routes

Equivalent exposure by these routes has not been established in the cited human studies. FDA distinguishes DAC, non-DAC and their salt forms. [1–3]

Dosing by Goal

• GH/IGF-I practice description: The educational attachment explicitly names CJC-1295 with DAC and describes dosing 2–3 hours after the last meal. No course duration or clinical recovery outcome is supplied. [7]

Dosing Protocol

Typical Range: 600 mcg

Frequency: Once weekly

Cycle: Not specified [7]

Loading Phase: No loading regimen specified in the practitioner source. [7]

Maintenance: No separate maintenance phase specified. [7]

600 mcg is one author-described DAC schedule, not an established typical range or FDA recommendation. No cycle duration is given. [7]

Stacking Guide

• Trials: 20–250 µg/kg spans separate DAC-alone arms, not a titration range. Exact doses and dates are in the Research table. Endpoints concern GH/IGF-I, not injury healing; the reports did not establish added clinical benefit from DAC+ipamorelin, HGH/IGF-I or BPC/TB-500. [1–3]
• DAC practice: the educational attachment explicitly describes 600 µg weekly, 2–3 hours after the last meal. It supplies no validated recovery endpoint or cycle duration and is not an FDA dosing recommendation. [7]
• No-DAC mixture: the document specifies 1 mg/mL of each ingredient and 0.05–0.1 mL per administration. Those values yield 50–100 µg each; they belong to CJC-1295 without DAC, not a DAC/ipamorelin regimen. [7]
• Preparation: receptor complementarity or a reported mixture does not establish same-syringe compatibility, sterility or storage stability. The clinical DAC salt was unspecified. [3]

Identity comparisons: CJC-1295 no DAC and CJC-1295 / Ipamorelin.

Administration Instructions

Route and trial schedule

The clinical long-acting agent was administered subcutaneously, not orally or intranasally. Single-dose study cohorts received 30, 60, 125 or 250 µg/kg. Repeated-dose cohorts received exactly 30 or 60 µg/kg on days 0 and 14, or 30 or 20 µg/kg on days 0, 7 and 14. The programme had 28- and 49-day observation periods; an observation period is not an injection cycle. [1,3]

Unit conversion: body-weight exposure is not a flat weekly dose

Multiply µg/kg by body weight in kg to obtain µg per administration, then divide by 1,000 for mg. The following is arithmetic for a hypothetical 70 kg body weight, not a prescribed regimen or a new study arm.

The practitioner document’s 600 µg once weekly is a flat practice figure and not one of these weight-based trial arms. [7]

Trial assessments and accumulation

The pulse study sampled every 20 minutes for 12 hours, before exposure and one week afterwards. Repeated doses in Study 2 produced higher exposure and IGF-I responses than the initial dose; IGF-I remained above baseline through day 28. The long half-life means that a new administration can occur while prior exposure remains. [1–3]

Formulation and preparation

FDA identifies DAC and non-DAC as different active moieties and describes the clinical DAC compound without a specified salt form. A paper’s µg/kg dose does not establish the concentration, diluent, multi-use handling or expiry of a retail vial. No universal bacteriostatic-water recipe or refrigerated lifetime is inferred from these hormone studies. [3]

The FDA chemical-handling review records −20°C for DAC free-base powder and 4°C for dissolved peptide from cited source handling information. Those temperatures are not a validated human-use shelf life or proof of same-syringe compatibility. [3]

Side Effects & Safety

• Injection-site and urticarial reactions are reported. [1,3]
• Headache and systemic vasodilation are reported. [1,3]
• FDA identifies increased heart rate and systemic vasodilatory reactions among serious safety concerns. [3,5]
• Limited clinical data leave potential immunogenicity and uncommon adverse events insufficiently characterised. [3,5]
• Teichman reported no serious adverse reactions in its short 28-/49-day healthy-adult studies; this does not establish long-term safety. [1]
• Safety of prolonged GH/IGF-I exposure and use in vulnerable populations remains insufficiently characterised. [1–3]

Contraindications

CJC-1295 has no approved prescribing-information contraindication list. Safety data are limited for pregnancy, breastfeeding, children, active malignancy, significant endocrine disease and concomitant endocrine treatments. These are evidence limitations and clinical cautions, rather than established CJC-1295-specific contraindications. [1–3]

Legal Status by Region

FAQ

What is the difference between CJC-1295 with DAC and no DAC?

DAC adds an albumin-binding modification and prolonged exposure; the clinical DAC agent had an estimated half-life of 5.8–8.1 days. FDA treats the DAC and non-DAC forms as distinct active moieties. Bedtime no-DAC schedules are therefore separate from the DAC trial schedules. [1–3]

Which single doses were tested in the human DAC trials?

The single-dose study had separate 30, 60, 125 and 250 µg/kg subcutaneous cohorts. Ionescu/Frohman used a single 60 or 90 µg/kg dose in its GH-pulsatility study. These are body-weight-based research doses for different cohorts. [1–3]

How often was DAC given in the repeat-dose study?

Two cohorts received 30 or 60 µg/kg on days 0 and 14. Two others received 30 or 20 µg/kg on days 0, 7 and 14. Each cohort contained five active participants and one placebo participant; the four schedules were not successive titration steps for one patient. [1,3]

How long did the trial schedules and follow-up last?

The repeat-dose schedules placed two or three administrations within 14 days. The principal studies lasted 28 and 49 days, and repeated-dose IGF-I elevation was reported through day 28. Those observation periods are different from an 8–12-week treatment cycle. [1,3]

Is there a published weekly DAC dosing description?

The practitioner educational attachment in FDA docket FDA-2024-N-4777-0002 describes 600 µg (0.6 mg) once weekly, 2–3 hours after the last meal. It gives no cycle duration. This is the attachment author’s educational description, not an FDA dosing recommendation or a clinical efficacy trial. [7]

How long did GH and IGF-I responses last after one dose?

Across Teichman’s studied exposures, mean GH rose 2–10-fold for at least six days and mean IGF-I 1.5–3-fold for 9–11 days. The estimated compound half-life was 5.8–8.1 days. Response ranges describe the trial groups rather than a guaranteed individual response. [1]

Does GH remain pulsatile with DAC?

Yes, in the cited physiological study. One week after a single 60 or 90 µg/kg dose, pulse frequency and magnitude were unchanged; trough GH was 7.5-fold higher, mean GH 46% higher and IGF-I 45% higher. [2]

How does the published bedtime CJC/ipamorelin mixture differ?

The same educational attachment explicitly labels that mixture as CJC-1295 w/o DAC plus ipamorelin, at 1 mg/mL each. Its 0.05–0.1 mL bedtime volume supplies 50–100 µg of each ingredient, five days weekly. This is a separate no-DAC formulation, not the 600 µg once-weekly DAC description. [7]

Research References

1. 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. 2006. Teichman et al. Primary report of randomised human pharmacokinetic/pharmacodynamic trials.
2. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. 2006. Ionescu and Frohman. Primary human physiological study.
3. FDA evaluation of CJC-1295-related bulk drug substances for the December 2024 Pharmacy Compounding Advisory Committee. Official identity, safety and regulatory assessment; not a primary efficacy trial.
4. Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analog. 2005. Jetté et al.; primary cell-based and rat research.
5. FDA: Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Current official safety page; CJC-1295 under nominated-but-withdrawn substances.
6. WADA 2026 Prohibited List. Official list; CJC-1295 explicitly named in S2.2.4.
7. CJC 1295 — practitioner educational attachment in public docket FDA-2024-N-4777-0002. Documents 600 µg once weekly explicitly for the DAC form; practice description, not an FDA dosing recommendation or efficacy trial.
8. Activation of the GH/IGF-1 axis by CJC-1295, a long-acting GHRH analog, results in serum protein profile changes in normal adult subjects. Exploratory human serum-biomarker study.

For educational and research purposes only. Not medical advice.