CJC-1295 DAC: Long-Acting GHRH with Drug Affinity Complex
A modified GHRH analogue with extended half-life through albumin binding, enabling sustained growth hormone elevation.
Quick Reference
| Research Dosage | 1-2mg per week |
|---|---|
| Frequency | Once or twice weekly |
| Administration | Subcutaneous injection |
| Half-Life | 6-8 days |
| Reconstitution | 2mL bacteriostatic water per 5mg vial |
| Storage | Refrigerate after reconstitution, use within 4-6 weeks |
CJC-1295 DAC represents a different approach to growth hormone releasing hormone (GHRH) therapy compared to its No DAC counterpart. The Drug Affinity Complex (DAC) modification extends the half-life from approximately 30 minutes to 6-8 days, enabling weekly dosing while maintaining sustained GHRH receptor stimulation.
The DAC technology enables binding to serum albumin – the most abundant protein in blood. This creates a circulating reservoir of peptide that releases slowly over days, producing sustained GH elevation rather than discrete pulses.
This fundamental difference (sustained vs. pulsatile GH elevation) determines when to use each version and what research applications each suits.
CJC-1295 DAC vs No DAC: Understanding the Difference
This is the critical distinction that determines which version to use:
| Property | CJC-1295 DAC | CJC-1295 No DAC |
|---|---|---|
| Also Called | DAC:GRF | Mod GRF 1-29 |
| Half-Life | 6-8 days | ~30 minutes |
| GH Pattern | Sustained elevation | Pulsatile (discrete bursts) |
| Dosing | 1-2x weekly | Multiple times daily |
| Ipamorelin Combo | Less common | Very common |
| GH Physiology | Non-physiological | Mimics natural |
| Convenience | Higher | Lower |
When to Choose DAC
- Weekly dosing convenience is important
- Sustained GH elevation is desired for research
- Less frequent administration preferred
When to Choose No DAC
- Pulsatile GH release desired (mimics natural)
- Combination with Ipamorelin (coordinated timing)
- Research requiring GH pulses rather than baseline elevation
Research Applications
Sustained GH Elevation Research
CJC-1295 DAC produces continuous GHRH receptor stimulation:
- Elevated baseline GH levels throughout the week
- Increased IGF-1 over extended periods
- Different physiological profile than pulsatile release
- Research into sustained vs. pulsatile GH effects
IGF-1 Research
Clinical studies documented significant IGF-1 effects:
- IGF-1 elevation lasting 10+ days after single doses
- Cumulative effects with repeated administration
- Sustained IGF-1 elevation profile ideal for certain research models
Convenience-Focused Protocols
When research requires GH axis stimulation but frequent dosing is impractical:
- Weekly administration sufficient for maintained effect
- Reduces injection frequency compared to No DAC or other GHRH analogues
- Simplified protocols with fewer variables
Dosage Information
Standard Research Dosages
Dosages commonly referenced in research literature range from 1-2mg per week. This can be administered as a single weekly dose or split into two doses.
Dosage Protocols
Once weekly: 1-2mg administered at the same time each week
Twice weekly: 0.5-1mg administered twice weekly (e.g., Monday and Thursday)
The extended half-life means more frequent dosing is unnecessary and may lead to accumulation beyond intended levels.
Administration
CJC-1295 DAC is administered via subcutaneous injection. Common injection sites include the abdominal area, thigh, or upper arm. Rotating injection sites is recommended to prevent localised reactions.
Cycle Duration
Research protocols typically range from 8-12 weeks. The sustained nature of DAC means effects build over time with repeated weekly doses. Some protocols include washout periods between cycles to assess baseline effects.
Reconstitution Guide
Required Materials
- CJC-1295 DAC lyophilised powder (5mg vial)
- Bacteriostatic water (water containing 0.9% benzyl alcohol)
- Sterile insulin syringe for reconstitution
- Alcohol swabs for sterile technique
Reconstitution Steps
- Allow the CJC-1295 DAC vial to reach room temperature before reconstitution
- Draw 2mL of bacteriostatic water into the syringe
- Insert the needle into the vial and direct the stream of water down the inside wall of the vial – do not spray directly onto the powder
- Allow the powder to dissolve naturally without shaking. Gentle swirling is acceptable if needed. Complete dissolution typically occurs within a few minutes. The solution should be clear with no visible particles.
- Store reconstituted solution refrigerated at 2-8°C immediately after reconstitution
Concentration Reference Table
| Vial Size | Water Added | Concentration | 1mg Dose | 2mg Dose |
|---|---|---|---|---|
| 5mg | 1mL | 5mg/mL | 20 units (0.2mL) | 40 units (0.4mL) |
| 5mg | 2mL | 2.5mg/mL | 40 units (0.4mL) | 80 units (0.8mL) |
| 5mg | 2.5mL | 2mg/mL | 50 units (0.5mL) | 100 units (1mL) |
Storage Guidelines
Lyophilised (Powder) Form
- Refrigeration (2-8°C) recommended for optimal stability
- Stable for 12+ months when refrigerated
- Freezing (-20°C) extends stability to 24+ months
- Protect from light and moisture
- Keep vial sealed until ready for reconstitution
Reconstituted Solution
- Must be refrigerated at 2-8°C
- Stable for 4-6 weeks when stored correctly
- Do not freeze after reconstitution – freezing can damage the peptide structure
- Avoid repeated temperature fluctuations
- Use sterile technique when drawing doses to prevent contamination
- If solution becomes cloudy or contains particles, discard and reconstitute a fresh vial
The Science: How CJC-1295 DAC Works
Drug Affinity Complex Technology
The DAC modification is the key innovation that distinguishes this peptide from other GHRH analogues. Understanding how it works explains the unique pharmacokinetic profile:
Albumin Binding Mechanism
- Albumin is the most abundant blood protein (~35-50 g/L in serum)
- The DAC modification enables reversible binding to circulating albumin
- Bound peptide is protected from enzymatic degradation
- Slow dissociation from albumin maintains active peptide levels over days
- Creates a "reservoir" effect that sustains activity
Pharmacokinetic Profile
A single dose of CJC-1295 DAC produces:
- Initial peak GH release within hours of administration
- Sustained GH elevation maintained over 6-8 days
- Gradual decline as peptide clears from circulation
- Cumulative effect with repeated weekly doses
GHRH Receptor Activation
Like all GHRH analogues, CJC-1295 DAC works by binding to GHRH receptors on pituitary somatotroph cells:
- Activates GHRH-R (Growth Hormone Releasing Hormone Receptor)
- Stimulates synthesis and secretion of growth hormone
- Works through the natural GH axis rather than bypassing it
- GH release remains subject to somatostatin feedback
Sustained vs. Pulsatile Release
The extended half-life creates a fundamentally different GH profile than natural secretion or short-acting GHRH:
- Natural GH: Released in discrete pulses, especially during sleep
- CJC-1295 No DAC: Produces pulses when administered, mimicking natural pattern
- CJC-1295 DAC: Produces sustained elevation, non-physiological but convenient
Whether sustained or pulsatile GH elevation is preferable depends on specific research objectives.
Technical Specifications
| Systematic Name | DAC:GRF (Drug Affinity Complex Growth Hormone Releasing Factor) |
|---|---|
| Other Names | CJC-1295 with DAC, CJC with DAC, DAC:GRF, CJC DAC, Drug Affinity Complex GRF, Long-Acting CJC |
| Amino Acid Count | 30 (modified GHRH 1-29 + DAC) |
| Sequence | 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 |
| Molecular Formula | C165H269N47O46 |
| Molecular Weight | ~3647 Da |
| CAS Number | 863288-34-0 |
| Appearance | White to off-white lyophilised powder |
| Solubility | Freely soluble in water and aqueous buffers |
| Purity (PurposeLabs) | ≥99% (HPLC verified) |
| Storage (Lyophilised) | -20°C long-term, 2-8°C short-term |
| Storage (Reconstituted) | 2-8°C, use within 4-6 weeks |
Frequently Asked Questions
Common questions about CJC-1295 DAC research
What is the difference between CJC-1295 DAC and CJC-1295 No DAC?
The critical difference lies in the Drug Affinity Complex (DAC) modification. CJC-1295 DAC has an extended half-life of 6-8 days due to albumin binding, producing sustained GH elevation with weekly dosing. CJC-1295 No DAC (Mod GRF 1-29) has a ~30 minute half-life, producing pulsatile GH release that mimics natural physiology and requires multiple daily doses. Choose DAC for convenience and sustained elevation; choose No DAC for pulsatile release and Ipamorelin combinations.
How does the Drug Affinity Complex (DAC) extend half-life?
The DAC modification enables the peptide to bind reversibly to serum albumin, the most abundant protein in blood (~35-50 g/L). This albumin binding protects the peptide from degradation and creates a circulating reservoir that releases slowly over days. The bound peptide gradually dissociates to maintain active levels, extending the effective half-life from minutes to 6-8 days.
Can CJC-1295 DAC be combined with Ipamorelin?
While possible, this combination is less common than CJC-1295 No DAC with Ipamorelin. The timing coordination that makes the No DAC/Ipamorelin combination effective (synchronised GHRH + GHRP pulse) is not achievable with DAC due to its sustained release profile. If combining GH secretagogues, CJC-1295 No DAC is typically preferred for Ipamorelin stacks.
What is the optimal dosing frequency for CJC-1295 DAC?
Research protocols typically utilise once or twice weekly administration at 1-2mg total weekly. The extended 6-8 day half-life means more frequent dosing is unnecessary and may lead to accumulation. Some protocols use a single weekly dose, while others split into two doses for more even levels.
How long does IGF-1 elevation last after a CJC-1295 DAC dose?
Clinical studies documented IGF-1 elevation lasting 10+ days following single doses of CJC-1295 DAC. With repeated weekly administration, cumulative effects create sustained IGF-1 elevation throughout the research period. This prolonged IGF-1 response distinguishes DAC from the shorter-acting No DAC version.
Is the GH release pattern from CJC-1295 DAC physiological?
No. CJC-1295 DAC produces sustained, non-physiological GH elevation rather than the pulsatile pattern of natural GH secretion. Natural GH is released in discrete pulses, particularly during sleep. If mimicking physiological GH patterns is important for your research, CJC-1295 No DAC provides pulsatile release more consistent with natural secretion.
What are the storage requirements for CJC-1295 DAC?
Lyophilised (powder) form: refrigeration (2-8°C) recommended, stable for 12+ months. Freezing (-20°C) extends stability further. Reconstituted solution: must be refrigerated at 2-8°C, stable for 4-6 weeks. Do not freeze after reconstitution. Protect from light and use sterile technique when drawing doses.
What is the molecular weight of CJC-1295 DAC?
CJC-1295 DAC has a molecular weight of approximately 3647 Daltons (Da). This is larger than the No DAC version due to the Drug Affinity Complex modification.
Quality: Australian University Testing
Why Peptide Quality Matters
The research peptide market contains products of highly variable quality. Independent testing of products from various suppliers has revealed significant issues:
- Purity levels as low as 50% in products claiming "99% purity"
- Incorrect amino acid sequences (entirely wrong peptides)
- Truncated sequences (missing amino acids)
- Bacterial endotoxin contamination
- Oxidised or degraded peptides with reduced activity
Our Testing Protocol
Every batch of CJC-1295 DAC from PurposeLabs undergoes comprehensive testing at a leading proteomics laboratory based at an Australian university in Sydney – one of Australia's premier analytical facilities.
Confirms purity levels of ≥99%, identifies any impurities or degradation products.
Verifies exact molecular weight, confirms correct amino acid sequence.
Determines actual peptide content versus salt, moisture, and counter-ions.
Why Australian University Testing?
Our testing partner is an established, verifiable proteomics facility at a major Australian university, with published research credentials, transparent methodology, and no commercial conflict of interest. This contrasts with overseas "certificates of analysis" from unknown or unverifiable laboratories.
Shop CJC-1295 DAC
Australian university tested. 99%+ purity verified by HPLC and mass spectrometry. Fast shipping from Sydney.
| Product | Size | Price |
|---|
References
Key studies for researchers seeking primary literature:
- Teichman SL, et al. "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." Journal of Clinical Endocrinology & Metabolism, 2006.
- Ionescu M, Bhawanie RN. "The biology of the growth hormone-releasing hormone receptor." Reviews in Endocrine and Metabolic Disorders, 2007.
- Alba M, et al. "Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout mouse." American Journal of Physiology-Endocrinology and Metabolism, 2006.
- Jetté L, et al. "hGH1-44-albumin fusion protein that confers prolonged half-life to a GHRH peptide." Bioconjugate Chemistry, 2005.
- Johansen PB, et al. "Pharmacokinetics of a long-acting GHRH-albumin fusion protein in rats." Growth Hormone & IGF Research, 2006.
Disclaimer
All products sold by PurposeLabs are intended for laboratory and research use only. They are not intended for human or animal consumption. The information provided is for educational purposes only and should not be construed as medical advice. Consult with qualified healthcare professionals for any health-related decisions.
CJC-1295 DAC is not approved by the TGA for therapeutic use in Australia. Products are sold strictly for research purposes in accordance with Australian regulations.