What Is CJC-1295?

CJC-1295 is a synthetic, long-acting analogue of growth hormone-releasing hormone, abbreviated GHRH. It was developed by ConjuChem using a technology called the Drug Affinity Complex, or DAC, to attach the peptide to circulating albumin after administration.

Main research themes

• Prolonged stimulation of endogenous growth hormone
• Sustained IGF-1 elevation
• Preservation of pulsatile GH secretion
• Albumin-based peptide half-life extension
• Growth-hormone deficiency research
• Body composition and anabolic signaling
• GH-axis biomarkers and anti-doping detection

🧬 Structure, Sequence, and DAC Chemistry

Modified GHRH backbone

H-Tyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Gln-Ser-Tyr-Arg-Lys-Val-Leu-Ala-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg-Lys(DAC)-NH₂

CJC-1295 uses a stabilized GHRH(1-29) backbone with four substitutions and a C-terminal lysine carrying the DAC reactive group.

D-Ala2

D-Ala at position 2 increases resistance to dipeptidyl peptidase-IV cleavage at the N terminus.

Gln8, Ala15, and Leu27

These substitutions improve stability while preserving GHRH-receptor agonism.

Lys30-DAC

The added lysine carries a maleimide-containing chemical linker designed to react with a free thiol on albumin.

Why molecular weight varies across listings

Reported values may differ depending on whether the calculation includes the intact maleimide, hydrolyzed maleimide, acetate or TFA counterions, hydration, or a vendor-specific representation. Lot identity should be established by intact LC-MS and site-specific peptide mapping rather than a catalog number alone.

CJC-1295 vs Modified GRF 1-29

Why mislabeling matters

A study designed around a brief GH pulse may produce very different exposure when true DAC-containing CJC-1295 is used. Conversely, no-DAC material cannot reproduce CJC-1295’s albumin-linked pharmacokinetics.

COA requirement

A certificate should explicitly state “CJC-1295 with DAC” and demonstrate the reactive DAC group, attachment site, and albumin-binding capability.

Albumin Binding and Prolonged Action

Albumin cysteine-34

Human serum albumin contains a reactive free cysteine at position 34. The CJC-1295 maleimide is designed to form a covalent thioether bond with this site.

In-vivo bioconjugation

The peptide is administered as an unconjugated molecule and then attaches to albumin in circulation.

Half-life extension

Albumin association reduces renal filtration and proteolytic clearance, extending biological activity from minutes to days.

Potential sources of failure

• Hydrolysis of the maleimide before administration
• Premature reaction with thiol-containing contaminants
• Incorrect DAC attachment site
• Incomplete DAC substitution
• Aggregation or self-adduct formation
• Loss of receptor potency after modification

Albumin binding changes safety

Long persistence means that excessive exposure, elevated IGF-1, vasodilatory reactions, or other adverse effects may not resolve quickly.

📅 Development and Research Timeline

• 1980s–1990s: GHRH biology and short active fragments were characterized.
• Early 2000s: ConjuChem developed albumin-binding DAC technology for peptide half-life extension.
• 2005: CJC-1295 was identified as a long-lasting GHRH analogue capable of albumin bioconjugation.
• 2006: Human studies reported prolonged, dose-dependent increases in GH and IGF-1 after subcutaneous CJC-1295.
• 2006: Detailed endocrine sampling showed preserved GH pulsatility with increased mean and trough GH.
• 2006: CJC-1295 normalized growth and body composition in GHRH-knockout mice.
• 2009: Proteomic research documented serum-protein changes after GH/IGF-1-axis activation.
• 2010s: CJC-1295 became widely marketed in research and compounded-peptide settings despite lack of approval.
• December 2024: FDA’s Pharmacy Compounding Advisory Committee reviewed CJC-1295-related bulk substances.
• May 14, 2026: FDA continued to classify CJC-1295 among compounded substances with identified significant safety risks pending further evaluation.
• 2026: WADA continued to explicitly prohibit CJC-1295.

🧠 How Does CJC-1295 Work?

1. GHRH receptor binding

CJC-1295 acts on GHRH receptors located on pituitary somatotroph cells.

2. Gs and cyclic AMP

Receptor activation stimulates Gs protein, adenylate cyclase, cyclic AMP, and protein kinase A.

3. Growth-hormone release

Intracellular signaling promotes synthesis and exocytosis of endogenous GH.

4. IGF-1 production

Released GH stimulates hepatic and local production of IGF-1.

5. Sustained receptor exposure

Unlike short-acting GHRH fragments, albumin-bound CJC-1295 continues to provide receptor stimulation over several days.

🎯 Receptor Profile

Dependence on pituitary reserve

CJC-1295 requires functioning pituitary somatotroph cells. It is not equivalent to direct recombinant GH replacement.

No ghrelin-receptor agonism

CJC-1295 does not directly activate GHSR-1a. Commercial combinations with ipamorelin add a separate ghrelin-receptor mechanism.

Growth-Hormone Pulsatility and IGF-1

Preserved pulses

Detailed human sampling found that pulsatile GH secretion persisted during prolonged CJC-1295 exposure.

Increased trough GH

CJC-1295 raised GH concentrations between pulses, producing a higher endocrine baseline than short-acting GHRH.

Increased mean GH

Overall mean GH secretion increased significantly.

Sustained IGF-1

IGF-1 remained elevated for approximately nine to eleven days after single administration in published studies.

Cumulative effect

Repeated doses produced accumulation of endocrine effect, especially for IGF-1.

Clinical interpretation

Preserved pulsatility does not mean physiologic exposure. Elevated trough and mean GH can still create pharmacologic effects and risk.

Human Clinical Evidence

Healthy-adult trials

Published phase I/II studies evaluated subcutaneous CJC-1295 in healthy adults.

Single-dose findings

GH increased for six days or longer, while IGF-1 remained elevated for approximately nine to eleven days.

Repeated-dose findings

Multiple administrations produced sustained and cumulative increases in IGF-1.

Tolerability in early trials

The original publication described the compound as relatively well tolerated at selected studied doses, but the trials were small and not designed to detect uncommon or long-term adverse events.

Outcome limitations

The studies primarily measured GH, IGF-1, and pharmacodynamic markers. They did not establish clinically meaningful improvements in:

• Muscle strength
• Body-fat reduction
• Sleep
• Injury recovery
• Longevity
• Quality of life
• Cardiovascular outcomes

No approved clinical-development endpoint

CJC-1295 did not progress to an approved medicine.

Body Composition, Muscle, and Recovery Research

Biological rationale

GH and IGF-1 influence protein synthesis, lipolysis, collagen turnover, bone, connective tissue, and muscle.

Animal findings

CJC-1295 supported normal growth and body composition in GHRH-knockout mice.

Human evidence gap

No controlled human trial establishes CJC-1295 as effective for increasing muscle, reducing fat, improving strength, or accelerating recovery.

Hormones are surrogate markers

Increased GH and IGF-1 do not automatically translate to useful functional outcomes.

Recovery claims

No validated evidence establishes treatment of tendon, ligament, muscle, surgical, or athletic injuries.

Metabolic and Glucose Considerations

GH and insulin sensitivity

Growth hormone can increase lipolysis but may reduce insulin sensitivity and raise blood glucose.

IGF-1 complexity

IGF-1 has insulin-like actions, but net glucose effects depend on GH exposure, nutrition, baseline metabolism, and treatment duration.

Long exposure

DAC-mediated persistence can prolong metabolic effects beyond the period expected from short GHRH analogues.

Human uncertainty

Long-term diabetes risk, fasting-glucose effects, and interactions with insulin or diabetes medicines are not established.

Sleep and Nocturnal GH Research

Natural GH physiology

The largest normal GH pulse often occurs during early slow-wave sleep.

Continuous background stimulation

CJC-1295 preserves pulses but also raises GH trough levels throughout the day and night.

No approved sleep indication

No controlled trial establishes CJC-1295 as a treatment for insomnia, sleep quality, circadian disorders, or fatigue.

Sleep-apnea concern

Chronic GH and IGF-1 elevation may contribute to soft-tissue growth and potentially worsen obstructive sleep apnea in susceptible individuals.

Animal and Preclinical Research

GHRH-knockout mice

Daily CJC-1295 restored growth and normalized body composition in mice unable to produce endogenous GHRH.

Albumin-bioconjugation studies

Preclinical experiments confirmed prolonged activity after albumin attachment.

Serum-protein changes

Proteomic studies identified downstream changes associated with activation of the GH/IGF-1 axis.

Translation limits

Animal growth models cannot establish safe performance, body-composition, or anti-aging outcomes in healthy humans.

Major Evidence Limitations

• No FDA-approved indication
• Small early human trials
• Hormonal rather than clinical endpoints
• No long-term randomized safety program
• No validated anti-aging or bodybuilding benefit
• No established obesity or recovery indication
• No approved dose, route, or monitoring framework
• Commercial confusion between DAC and no-DAC products
• Variable molecular-weight and salt reporting
• Maleimide hydrolysis can change pharmacology
• Potential premature reaction with thiol-containing contaminants
• Limited data on malignancy, glucose, cardiovascular, and reproductive risks
• No FDA-reviewed current finished-product specification

FDA and Anti-Doping Status

FDA approval

CJC-1295 is not FDA approved for any indication.

FDA compounding concerns

FDA states that compounded CJC-1295 may present immunogenicity and peptide-related impurity risks. The agency also reports serious adverse events associated with CJC-1295, including increased heart rate and systemic vasodilatory reaction.

Current 503A status

As of May 14, 2026, CJC-1295 remained among bulk drug substances with identified significant safety risks pending further evaluation.

WADA prohibition

The 2026 WADA Prohibited List explicitly names CJC-1295 among prohibited GHRH analogues.

Research-use labeling

A research-use label does not establish clinical legality, safety, or anti-doping compliance.

Potential Side Effects and Safety Considerations

FDA-identified serious adverse events

• Increased heart rate
• Systemic vasodilatory reaction

Growth-axis effects

• Elevated IGF-1
• Edema and fluid retention
• Arthralgia and myalgia
• Carpal-tunnel-type symptoms
• Headache
• Soft-tissue growth
• Potential worsening of sleep apnea

Metabolic concerns

• Reduced insulin sensitivity
• Hyperglycemia
• Potential diabetes risk

Malignancy concern

GH and IGF-1 activate cell-growth and survival pathways. Long-term stimulation may be inappropriate in active malignancy or significant oncologic risk.

Immunogenicity

Peptide impurities, aggregates, hydrolyzed DAC species, premature adducts, or altered albumin conjugates may increase anti-drug-antibody risk.

Product-quality risks

• No-DAC material mislabeled as CJC-1295
• Incorrect DAC attachment site
• Hydrolyzed or inactive maleimide
• Premature thiol adducts
• Incorrect sequence or stereochemistry
• Inaccurate net content
• Endotoxin, microbial contamination, or particles

🧪 Laboratory Testing Methods

📄 How to Interpret a CJC-1295 COA

1. Confirm the product contains DAC.
2. Do not accept “CJC-1295 no DAC” as the same compound.
3. Confirm the complete modified GHRH sequence.
4. Verify D-Ala2, Gln8, Ala15, and Leu27 substitutions.
5. Confirm the added Lys30.
6. Map the maleimidopropionyl DAC group to Lys30.
7. Measure intact versus hydrolyzed maleimide.
8. Demonstrate thiol reactivity and albumin Cys34 conjugation.
9. Confirm C-terminal amidation.
10. Use intact LC-MS plus MS/MS peptide mapping.
11. Measure clipping, oxidation, deamidation, epimers, aggregates, and premature adducts.
12. State free base versus acetate or TFA salt.
13. Report net peptide content after correcting for water and counterions.
14. Use GHRH-receptor binding and cAMP potency assays.
15. Confirm potency after albumin conjugation.
16. For finished injectables, require sterility, endotoxin, particles, pH, osmolality, fill accuracy, container closure, and post-reconstitution stability.
17. A COA does not establish FDA approval, human safety, or clinical effectiveness.

📊 Comparison Tables

CJC-1295 vs Modified GRF 1-29

CJC-1295 vs Sermorelin vs Tesamorelin

CJC-1295 vs Recombinant Growth Hormone

Basic CJC Claim vs Research-Qualified CJC-1295

🖼️ Original Diagram Specifications

1. Sequence architecture: Modified GHRH backbone with D-Ala2, Gln8, Ala15, Leu27, and Lys30-DAC highlighted.
2. DAC chemistry: Maleimide reaction with albumin Cys34.
3. Pharmacokinetic comparison: Native GHRH, Modified GRF 1-29, and albumin-bound CJC-1295.
4. GHRH-receptor pathway: Pituitary receptor, cAMP, GH pulse, liver IGF-1, and peripheral tissues.
5. Pulsatility diagram: Preserved GH peaks with elevated trough and mean concentrations.
6. Risk map: IGF-1 elevation, hyperglycemia, edema, tachycardia, vasodilation, malignancy, and immunogenicity.
7. COA workflow: Sequence, DAC site, maleimide integrity, albumin binding, potency, sterility, and stability.

❓ Frequently Asked Questions

Is CJC-1295 a peptide?

Yes. It is a chemically modified GHRH analogue with a Drug Affinity Complex.

What does DAC mean?

Drug Affinity Complex, a maleimide-containing linker that enables covalent albumin binding.

Is CJC-1295 without DAC the same compound?

No. It is more accurately called Modified GRF 1-29.

How does CJC-1295 bind albumin?

Its maleimide group reacts primarily with cysteine-34 of serum albumin.

What receptor does CJC-1295 activate?

The pituitary GHRH receptor.

Does it increase growth hormone?

Yes. Human studies demonstrated prolonged, dose-dependent GH increases.

Does it increase IGF-1?

Yes. Human studies reported sustained IGF-1 elevation for approximately nine to eleven days after a single dose.

Does CJC-1295 preserve GH pulses?

Yes, but it also raises mean and trough GH, so exposure is not simply physiologic.

Is CJC-1295 FDA approved?

No.

Does it build muscle or burn fat?

No controlled human trial establishes clinically meaningful muscle gain or fat loss.

Can it affect glucose?

Yes. Prolonged GH stimulation may reduce insulin sensitivity and increase blood glucose.

Can it affect heart rate or blood pressure?

FDA has identified increased heart rate and systemic vasodilatory reaction among serious adverse events associated with CJC-1295.

Is it prohibited in sports?

Yes. WADA explicitly prohibits CJC-1295.

What is the most important COA requirement?

Proof of an intact, functional DAC group attached at Lys30 with demonstrated albumin-binding capability.

Does 99% HPLC purity prove authentic CJC-1295?

No. Sequence, DAC integrity, attachment site, albumin binding, potency, net content, sterility, and stability must also be established.

Final Thoughts

CJC-1295 is a long-acting GHRH analogue whose defining feature is its Drug Affinity Complex. The maleimide-containing DAC group binds serum albumin, allowing the peptide to circulate and stimulate pituitary GHRH receptors for days rather than minutes.

Human studies demonstrate that CJC-1295 can produce prolonged, dose-dependent growth-hormone and IGF-1 elevation while preserving pulsatile GH secretion. However, the same studies primarily measured endocrine biomarkers and did not establish long-term clinical benefit for body composition, recovery, sleep, healthy aging, or quality of life.

The distinction from Modified GRF 1-29 is essential. A no-DAC product does not have CJC-1295’s albumin-binding pharmacology and should not be described as equivalent. FDA currently identifies safety concerns involving immunogenicity, peptide impurities, increased heart rate, and systemic vasodilatory reaction, and WADA prohibits the compound.

Analytical authentication requires the exact modified GHRH sequence, D-Ala2 and other substitutions, Lys30-DAC site mapping, intact-maleimide measurement, albumin Cys34 conjugation, albumin-bound receptor potency, counterion-corrected content, impurity profiling, sterility, and stability. A simple HPLC purity result cannot establish genuine CJC-1295 or suitability for human administration.

📚 References

1. Jetté L, et al. Human Growth Hormone-Releasing Factor 1-29 Albumin Bioconjugates Activate the GRF Receptor: Identification of CJC-1295 as a Long-Lasting GRF Analogue. Endocrinology. 2005.
2. Teichman SL, et al. Prolonged Stimulation of Growth Hormone and Insulin-Like Growth Factor I Secretion by CJC-1295 in Healthy Adults. Journal of Clinical Endocrinology & Metabolism. 2006.
3. Ionescu M, Frohman LA. Pulsatile Secretion of Growth Hormone Persists During Continuous Stimulation by CJC-1295. Journal of Clinical Endocrinology & Metabolism. 2006.
4. Alba M, et al. Once-Daily Administration of CJC-1295 Normalizes Growth in Growth Hormone-Releasing Hormone Knockout Mice. American Journal of Physiology. 2006.
5. Sackmann-Sala L, et al. Activation of the GH/IGF-1 Axis by CJC-1295 Results in Serum Protein Profile Changes. Growth Hormone & IGF Research. 2009.
6. Henninge J, et al. Identification of CJC-1295 in an Unknown Pharmaceutical Preparation. Drug Testing and Analysis. 2010.
7. Memdouh S, et al. Advances in the Detection of Growth Hormone-Releasing Hormone Synthetic Analogues. Drug Testing and Analysis. 2021.
8. U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding That May Present Significant Safety Risks: CJC-1295.
9. U.S. Food and Drug Administration. Pharmacy Compounding Advisory Committee Briefing Document for CJC-1295-Related Bulk Drug Substances. December 2024.
10. U.S. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act. Updated May 14, 2026.
11. U.S. Food and Drug Administration. Tailor Made Compounding LLC Warning Letter. April 1, 2020.
12. World Anti-Doping Agency. 2026 Prohibited List.
13. World Anti-Doping Agency. Scientific Research on Detection and Identification of CJC-1295 and Other GHRH Analogues.
14. International Council for Harmonisation. ICH Q1A(R2), Q2(R2), Q3A, Q3B, Q3C, Q5C, and Q6B.
15. United States Pharmacopeia General Chapters <621>, <71>, <85>, and <788>.

Identity, DAC chemistry, human evidence, current FDA status, anti-doping status, safety, and analytical recommendations reviewed in July 2026.