What is the difference between CJC-1295 DAC and CJC-1295 without DAC (Mod GRF 1-29)?

The key difference is half-life and GH release pattern. CJC-1295 DAC binds to albumin, extending its half-life to approximately 6–8 days and producing sustained, tonic GH elevation. CJC-1295 without DAC (Mod GRF 1-29) has a half-life of roughly 30 minutes and produces acute GH pulses, more closely mimicking natural pulsatile secretion. The DAC version requires less frequent dosing but does not replicate the physiological GH release pattern.

Is CJC-1295 DAC approved for human use?

No. CJC-1295 DAC is not approved for human therapeutic use by any regulatory authority including the MHRA, EMA, or FDA. Although it advanced to Phase II clinical trials, the pharmaceutical development programme was discontinued. It remains a research compound only.

How does CJC-1295 DAC compare to exogenous growth hormone injections?

CJC-1295 DAC stimulates the body's own GH production rather than introducing exogenous hormone. This means the pituitary remains involved, and feedback mechanisms (particularly somatostatin) are partially preserved. Exogenous GH suppresses endogenous production and bypasses physiological regulation entirely. However, CJC-1295 DAC's sustained stimulation pattern differs from natural pulsatile GH secretion.

Why was the CJC-1295 DAC clinical programme discontinued?

A serious adverse event (cardiac event) occurred during clinical trials, leading to a temporary clinical hold. Although investigators determined the event was likely unrelated to the study drug, ConjuChem Biotechnologies faced financial and development challenges and ultimately discontinued the programme. The compound itself was not conclusively linked to the adverse event.

Can CJC-1295 DAC be combined with Ipamorelin?

In research settings, GHRH analogues and GHRPs (growth hormone releasing peptides) are sometimes used together because they act through complementary mechanisms — GHRH amplifies GH pulse amplitude whilst GHRPs increase pulse frequency. However, this combination approach is more commonly discussed with the short-acting CJC-1295 (Mod GRF 1-29) rather than the DAC version, as the sustained nature of CJC-1295 DAC may make pulsatile GHRP co-administration less pharmacologically rational. No safety data exists for such combinations.

Is CJC-1295 DAC legal in the UK?

CJC-1295 DAC is not a controlled substance in the UK but is not licensed as a medicine. It may be available as a research chemical for legitimate scientific purposes. It is not legal to sell for human consumption, and it is prohibited by WADA in all competitive sports.

Fact-checked by the Peptide Authority Editorial Board · Last reviewed: 13 March 2026

Share:X Post LinkedIn

Hormonal & Endocrine•Updated 2026-03-13•7 min read

What Is CJC-1295 DAC? Benefits, Research & Safety

A modified growth hormone releasing hormone (GHRH) analogue featuring a Drug Affinity Complex (DAC) that extends its half-life to approximately 8 days, enabling sustained growth hormone elevation with less frequent dosing.

Share:X Post LinkedIn

Also known as:

CJC-1295 with Drug Affinity Complex

DAC:GRF

Modified GRF(1-29) with DAC

DAnimal/cell evidence onlyUK: Unlicensed (UK)WADA: Prohibited in sport

UK summary: Not a licensed UK medicine. The long-acting (1-2 week half-life) variant of CJC-1295, with original pharmaceutical development discontinued. Prohibited at all times under WADA S2.

Quick Facts

Overview

CJC-1295 DAC is a synthetic analogue of growth hormone releasing hormone (GHRH) that incorporates a unique Drug Affinity Complex (DAC) — a reactive chemical group that binds covalently to serum albumin following subcutaneous injection. This albumin-binding modification dramatically extends the peptide's half-life from approximately 30 minutes (as seen with standard CJC-1295 or Mod GRF 1-29) to roughly 6–8 days, enabling sustained elevation of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels with far less frequent administration. The base peptide is a 30-amino-acid GHRH analogue (also known as tetrasubstituted GRF(1-29)) in which four amino acid substitutions confer resistance to enzymatic degradation by dipeptidyl peptidase-IV (DPP-IV). The addition of the DAC moiety — a maleimidopropionic acid linker coupled to a lysine residue — allows the peptide to form a stable thioether bond with Cysteine-34 of circulating albumin, creating a long-lived bioconjugate. CJC-1295 DAC was originally developed by ConjuChem Biotechnologies (later ConjuChem LLC) and advanced into Phase II clinical trials for growth hormone deficiency and lipodystrophy. Although development was discontinued following a serious adverse event (unrelated to the compound per investigators), the peptide has remained a subject of research interest. CJC-1295 DAC is not approved for human therapeutic use by any regulatory authority including the MHRA, EMA, or FDA. All information presented here is for educational purposes based on published research.

Evidence standards summary

CJC-1295 DAC — evidence and risk at a glance

Twenty standard modules scored against the Peptide Authority evidence grading methodology. Missing modules indicate the field has not yet been characterised editorially — treat absences as uncertainty rather than reassurance.

01Evidence snapshot

DAnimal/cell evidence onlyOverall grade against our evidence grading methodology.

Not a licensed UK medicine. The long-acting (1-2 week half-life) variant of CJC-1295, with original pharmaceutical development discontinued. Prohibited at all times under WADA S2.

02Human evidence grade

DAnimal/cell evidence onlyStrength of evidence from published human trials.

03Preclinical evidence grade

BModerate human evidenceAnimal-model and in-vitro evidence quality.

04Regulatory status

UK: Not licensed for human therapeutic use. Not approved by the MHRA. Available only as a research chemical.
EU: Not authorised by the EMA for any indication. Classified as an investigational compound.
Notes: CJC-1295 DAC has undergone Phase I and Phase II clinical trials but is not approved for human use by any regulatory authority. The original pharmaceutical development programme was discontinued. Products available online are unregulated and may be of unknown quality, purity, or authenticity. WADA prohibits all GH-releasing peptides in competitive sport.

05Approved medical uses

None in the UK or EU as a finished medicine. (Or: not yet documented; treat as absence rather than approval.)

06Unapproved / promotional claims

Single weekly injection equivalent to daily GH.
Safer than HGH replacement.
Anti-ageing protocol.

07Common internet claims

Marketed by 'anti-ageing' clinics on extended half-life.
Sold by grey-market vendors as long-acting CJC-1295.

08Claim vs evidence

Claim	Evidence	Human evidence?	Regulatory concern	Safer wording
“More efficient than weekly CJC-1295 / Ipamorelin stacks”	D	Limited	High	DAC's sustained GH elevation differs from natural pulsatile release; whether that's a clinical advantage or disadvantage is unsettled. Original development was discontinued.
“Safe long-term anti-ageing protocol”	E	No	High	Sustained GH/IGF-1 elevation has theoretical safety concerns; long-term human data are absent.

09Safety uncertainty score

High

Limited human safety data; meaningful uncertainty about rare or long-term effects.

10Known adverse signals

Sustained (non-pulsatile) GH elevation differs from physiological release — unknown chronic effects.
WADA S2 prohibited.
Original pharmaceutical development discontinued.

11Drug-interaction uncertainty

High

Interaction picture sparse; meaningful uncertainty when combined with other medicines.

12Anti-doping status

WADA: Prohibited in sportWADA strict-liability framing applies.

13UK legal position

UK: Unlicensed (UK)

Not licensed for human therapeutic use. Not approved by the MHRA. Available only as a research chemical.

Read the full UK legal guide → Peptides and athletes (UK)

14EU legal position

Not authorised by the EMA for any indication. Classified as an investigational compound.

15What this page cannot tell you

Whether grey-market 'CJC-1295 DAC' contains the labelled compound.
Long-term safety of sustained GH/IGF-1 elevation in healthy adults.

16Last reviewed

Last reviewed: 13 March 2026

Next review due: 13 March 2027

Spotted an error or something out of date? Send a correction.

17Citation quality score

CLimited human evidenceQuality of the sources we cite, graded against the evidence grading methodology.

18Research gaps

Phase 3 trials for any indication absent.
Comparative-effectiveness vs daily GH or weekly CJC-1295 + Ipamorelin not published.

19Safer alternatives / established care pathways

Endocrinologist review for confirmed GH deficiency.
Licensed recombinant HGH where genuinely indicated.

20Doctor discussion prompts

Questions to ask a qualified clinician

These are starter questions you can adapt for a GP, specialist, pharmacist, or anti-doping advisor. The aim is to help you have a better-informed conversation — not to replace one.

Is CJC-1295 DAC a licensed UK medicine?
What is the WADA position?

Discovery & History

CJC-1295 DAC was developed by ConjuChem Biotechnologies, a Canadian biopharmaceutical company specialising in long-acting peptide therapeutics through their proprietary DAC technology platform. The technology was designed to overcome the fundamental pharmacokinetic limitation of native peptide hormones — their extremely short half-lives in circulation. The development built upon earlier work characterising modified GRF(1-29) analogues with enhanced DPP-IV resistance. ConjuChem's innovation was the addition of the Drug Affinity Complex, which enabled in vivo albumin binding and dramatic half-life extension without compromising receptor binding affinity. Phase I clinical trials were conducted in the early 2000s, demonstrating that a single subcutaneous injection could sustain elevated GH and IGF-1 levels for up to two weeks. Phase II trials followed, examining the compound in growth hormone deficiency and HIV-associated lipodystrophy. In 2006, a clinical trial participant experienced a serious adverse event (cardiac event), which led to a temporary clinical hold. Although investigators determined the event was unrelated to CJC-1295 DAC, the programme faced challenges, and ConjuChem ultimately discontinued development. Despite the cessation of formal pharmaceutical development, CJC-1295 DAC has remained widely discussed in research and biohacking communities, particularly in comparison to the non-DAC version (Mod GRF 1-29 or CJC-1295 without DAC), which requires more frequent dosing but offers pulsatile GH release patterns more closely mimicking natural physiology.

Mechanism of Action

CJC-1295 DAC exerts its effects through a multi-step process involving albumin conjugation, sustained GHRH receptor activation, and downstream growth hormone axis stimulation: **Albumin Binding and Half-Life Extension** Following subcutaneous injection, the maleimide group of the DAC moiety reacts with the free thiol of Cysteine-34 on circulating serum albumin, forming a stable covalent thioether bond. This bioconjugation effectively converts the peptide into a macromolecular complex (~67 kDa) that is protected from renal filtration, proteolytic degradation, and rapid clearance. The result is a biological half-life of approximately 6–8 days, compared to roughly 30 minutes for the unconjugated peptide. **GHRH Receptor Activation** The albumin-bound CJC-1295 DAC retains full agonist activity at the GHRH receptor (GHRHR), a G-protein-coupled receptor expressed primarily on somatotroph cells of the anterior pituitary gland. Receptor activation triggers: - Adenylate cyclase stimulation and cyclic AMP (cAMP) production - Protein kinase A (PKA) pathway activation - Transcription and release of stored growth hormone **Sustained vs Pulsatile GH Release** Unlike the standard CJC-1295 (Mod GRF 1-29), which produces discrete GH pulses reflecting its short half-life and is typically co-administered with a GHRP such as Ipamorelin, CJC-1295 DAC produces a sustained, tonic elevation of baseline GH and IGF-1 levels. This continuous stimulation pattern differs from natural GH secretion, which is characteristically pulsatile. **IGF-1 Elevation** Sustained GH release stimulates hepatic production of IGF-1, a key mediator of GH's anabolic effects on muscle, bone, and other tissues. Clinical data showed IGF-1 elevations of 1.5 to 3-fold above baseline persisting for 6–14 days following a single injection. **Somatostatin Interaction** CJC-1295 DAC's effects remain subject to negative feedback by somatostatin, meaning GH release is partially physiologically regulated despite the sustained stimulation. However, the continuous nature of GHRH receptor activation may partially override normal pulsatile regulation.

Researched Benefits

Based on preclinical and clinical research findings:

1
Sustained elevation of GH and IGF-1 levels for 6–14 days following a single injection in clinical studies
2
Reduced injection frequency compared to standard CJC-1295 (Mod GRF 1-29) — potentially once or twice weekly versus multiple daily doses
3
Increased lean body mass observed in Phase II clinical trial participants
4
Potential improvement in body composition with decreased visceral adiposity
5
Enhanced deep-wave sleep quality associated with elevated GH levels
6
Potential bone density benefits through sustained IGF-1 elevation
7
Improved recovery capacity and tissue repair associated with growth hormone axis stimulation
8
Maintained physiological feedback regulation (somatostatin responsiveness) unlike exogenous GH administration

Claim vs Evidence

How popular claims about CJC-1295 DAC stack up against the current research, graded using our public evidence grading methodology.

Claim	Evidence	Human evidence?	Regulatory concern	Safer wording
“More efficient than weekly CJC-1295 / Ipamorelin stacks”	D	Limited	High	DAC's sustained GH elevation differs from natural pulsatile release; whether that's a clinical advantage or disadvantage is unsettled. Original development was discontinued.
“Safe long-term anti-ageing protocol”	E	No	High	Sustained GH/IGF-1 elevation has theoretical safety concerns; long-term human data are absent.

Theoretical Dosing & Protocols

⚠️ Educational Only: The following information is derived from research literature and is not a prescription or recommendation. No standardised human dosing exists. Always consult a qualified healthcare professional.

Theoretical Dosage	1000–2000 mcg (1–2 mg) per injection (based on clinical trial dosing)
Frequency	Once or twice weekly due to extended half-life
Duration	Variable; clinical trials examined 4–12 week protocols
Notes	CJC-1295 DAC is NOT approved for human use. These are theoretical protocols derived from clinical trial data. The sustained GH elevation pattern differs from natural pulsatile release, which some researchers consider a potential disadvantage compared to short-acting GHRH analogues. The long half-life means effects cannot be rapidly reversed if adverse reactions occur. Always consult a qualified healthcare professional.

Administration Routes

Routes studied in research settings (educational only):

Subcutaneous injection (used in all clinical trials)
Intravenous injection (research settings only)

Half-Life	Stability
Approximately 6–8 days due to albumin conjugation (compared to ~30 minutes for CJC-1295 without DAC)	Lyophilised powder should be stored at -20°C; reconstituted solution should be refrigerated at 2–8°C and used within a limited timeframe; the DAC moiety is sensitive to hydrolysis under certain conditions

Safety Profile & Known Risks

Commonly Reported Side Effects

Injection site reactions including redness, swelling, itching, or induration
Water retention and peripheral oedema
Transient flushing and warmth following injection
Headache reported in clinical trial participants
Fatigue and somnolence, particularly in the first days following injection
Paraesthesia (tingling sensations) associated with GH elevation

Rare Risks & Concerns

Sustained GH elevation may carry risks associated with chronic growth hormone excess including insulin resistance and glucose intolerance
Theoretical risk of accelerating growth of undiagnosed tumours through prolonged IGF-1 elevation
Carpal tunnel syndrome-like symptoms with prolonged use
Unknown long-term cardiovascular effects — one serious cardiac adverse event occurred in clinical trials (deemed unrelated by investigators)
Potential for antibody formation against the peptide–albumin conjugate

Contraindications

Active malignancy or history of cancer (sustained IGF-1 elevation may promote tumour growth)
Pregnancy and breastfeeding (no safety data available)
Uncontrolled diabetes mellitus (GH can worsen glucose tolerance)
Active pituitary tumours or pituitary disease
Children and adolescents (risk of abnormal growth patterns)
Individuals with a history of carpal tunnel syndrome

UK & EU Regulatory Context

🇬🇧 United Kingdom

Not licensed for human therapeutic use. Not approved by the MHRA. Available only as a research chemical.

🇪🇺 European Union

Not authorised by the EMA for any indication. Classified as an investigational compound.

CJC-1295 DAC has undergone Phase I and Phase II clinical trials but is not approved for human use by any regulatory authority. The original pharmaceutical development programme was discontinued. Products available online are unregulated and may be of unknown quality, purity, or authenticity. WADA prohibits all GH-releasing peptides in competitive sport.

Clinical Studies Summary

Prolonged Stimulation of Growth Hormone (GH) and Insulin-Like Growth Factor I Secretion by CJC-1295

Phase I/II study demonstrating that a single injection of CJC-1295 DAC produced dose-dependent increases in GH (2–10 fold) and IGF-1 (1.5–3 fold) lasting 6–14 days in healthy subjects. The compound was well tolerated with primarily injection site reactions.

J Clin Endocrinol Metab. 2006View on PubMed

Looking for CJC-1295 DAC?

Source research-grade CJC-1295 DAC from a trusted UK supplier — third-party tested with certificate of analysis.

View at Supplier

Frequently Asked Questions

Questions to ask a qualified clinician about CJC-1295 DAC