CJC-1295 with DAC
Drug Affinity Complex : Growth Hormone-Releasing Factor (1-29) · CJC-1295 DAC · DAC:GRF · DAC:GRF (1-29) · Modified GRF 1-29 with DAC
Albumin-binding GHRH analogue that lifts GH and IGF-1 for days from one injection.
Typical dose
1000 mcg
1-2x weekly
Range
500–1000
mcg
Half-life
7 days
see Dosing
Evidence
Early human
Subcutaneous · Intramuscular
What it is
CJC-1295 with DAC is a growth hormone-releasing hormone (GHRH) analogue built on the first 29 amino acids of human GHRH. Four substitutions stabilise the backbone — D-Ala at position 2 blocks the enzyme DPP-4, Gln8 prevents asparagine deamidation, Ala15 raises potency and proteolytic resistance, and Leu27 stops methionine oxidation — and a maleimidopropionyl group — the Drug Affinity Complex — is attached to an added lysine at position 30. That group forms a covalent bond with circulating albumin, and albumin is a large, slowly cleared carrier, so the peptide stays in circulation for days instead of minutes.
That single change is the point of the molecule and also its main drawback. One injection produces a broad, sustained rise rather than a short spike: the phase 1 work in healthy adults measured GH at roughly 2-10x baseline for six days or more and IGF-1 at 1.5-3x baseline for nine to eleven days after a single dose. Follow-up work confirmed GH is still released in pulses under CJC-1295, but those pulses now sit on a raised floor of GHRH signalling.
ConjuChem carried CJC-1295 through early human trials and then dropped it. It has never been approved anywhere, and everything sold today is research-grade material of variable purity. The community keeps using it because it is the only GH secretagogue that works on a once- or twice-weekly schedule.
How it works
CJC-1295 binds the GHRH receptor on pituitary somatotrophs and triggers the same cAMP/PKA cascade native GHRH does, telling the pituitary to make and release its own growth hormone. Because the pituitary does the work, the ceiling is your own somatotroph capacity, and negative feedback from somatostatin and rising IGF-1 still applies.
The DAC linker changes the pharmacokinetics, not the receptor pharmacology. Tethering to albumin turns a roughly 30-minute peptide into one with a 6-8 day half-life, which is why blood levels accumulate across doses and IGF-1 keeps drifting upward over the first few weeks rather than settling after the first injection.
Dosing
Weekly totals above roughly 2 mg mostly add side effects rather than GH — levels accumulate for 3-4 weeks before plateauing, so judge the dose on IGF-1 bloodwork rather than on how the first week feels.
Reconstitution calculator
Pre-loaded with CJC-1295 with DAC’s vial size, water volume and typical dose. Change anything.
Typical: 1000 mcg · range 500–1000
Draw to
100 u
1 mL · 1 mg
Concentration
1 mg/mL
10 mcg per unit
Doses per vial
2
Vial lasts
7 days
CheckThe draw fills more than 90% of the barrel. Workable, but there is no room for an air bubble or a correction.
Once mixed
Refrigerated at 2-8C and used within 3-4 weeks; do not freeze a reconstituted vial.
Aim the bacteriostatic water down the inside wall of the vial rather than straight onto the cake, then swirl or roll gently — never shake. A 2 mg vial in 2 mL gives 1000 mcg/mL, so 1000 mcg is 1.0 mL, or 100 units on a U-100 insulin syringe.
Storage
Before mixing
Sealed, dry and dark at -20C for long-term storage; several months at 2-8C or a few weeks at room temperature are tolerated.
After mixing
Refrigerated at 2-8C and used within 3-4 weeks; do not freeze a reconstituted vial.
Reported benefits
- ▪Once- or twice-weekly dosing instead of daily or multi-daily injections
- ▪Sustained IGF-1 elevation without injecting recombinant GH
- ▪GH still comes from your own pituitary, so the axis is stimulated rather than replaced
- ▪Deeper sleep and easier recovery between sessions are the most consistently reported effects
- ▪Higher IGF-1 supports connective tissue and soft-tissue repair
- ▪Works additively with a GHRP, which acts through a separate receptor
Side effects
- ▪Water retention, puffiness and morning facial swelling
- ▪Numbness, tingling or frank carpal tunnel symptoms in the hands
- ▪Joint aches and stiffness, especially in wrists and knees
- ▪Injection-site redness, itching or a warm flush in the first hour
- ▪Reduced insulin sensitivity and higher fasting glucose with prolonged use
- ▪Head rush, light-headedness or transient tachycardia shortly after dosing
- ▪IGF-1 can sit in a supraphysiological range for the full week between doses
Do not use if
- ▪Active or suspected malignancy — GH and IGF-1 are trophic to existing tumours
- ▪Diabetes or pre-diabetes where further insulin resistance is unacceptable
- ▪Pregnancy and breastfeeding
- ▪Known pituitary tumour, or prior pituitary surgery or cranial irradiation
- ▪Active proliferative diabetic retinopathy
Evidence level — Early human
Small or early-phase human studies only.
Never approved in any market; clinical development was abandoned after early-phase trials and it is sold only as a research chemical.
Commonly run with
Ipamorelin
The selective GHRP: a clean GH pulse with almost no cortisol, prolactin or hunger.
300 mcg · 1-3x daily
GHRP-2
Potent, well-studied GHRP with a bigger pulse than ipamorelin and more cortisol.
100 mcg · 2-3x daily
GHRP-6
The original GHRP: solid GH release and the strongest hunger response of the group.
100 mcg · 2-3x daily
Hexarelin
The most potent GHRP, and the fastest to stop working if you run it continuously.
100 mcg · 1-2x daily
MK-677
Oral ghrelin mimetic that raises GH and IGF-1 for a full 24 hours from one daily dose.
10 mg · Once daily
CJC-1295 with DAC FAQ
What is the actual difference between CJC-1295 with and without DAC?+
The peptide backbone is the same tetrasubstituted GRF(1-29); DAC adds a lysine and a maleimide linker that binds albumin. That takes the half-life from about 30 minutes to 6-8 days, which converts a pulse-mimicking peptide into a continuous-signal one. Neither is stronger at the receptor — they just deliver the signal on completely different timescales.
Does the constant GHRH signal blunt natural GH pulsatility?+
Follow-up human work found GH pulses persist under CJC-1295, so pulsatility is not abolished. What changes is the trough: the baseline between pulses rises, which is closer to a continuous infusion than to normal physiology. The long-term consequences of holding that pattern for months have not been studied.
Do I still need a GHRP alongside it?+
Not strictly, but most people run one. GHRH analogues and ghrelin-receptor agonists like ipamorelin act on different receptors and their effects are more than additive when given together. Running CJC-1295 DAC alone produces a smaller GH response than the same dose paired with a GHRP.
Why does it take weeks to feel anything?+
With a 6-8 day half-life, blood levels keep accumulating for roughly four half-lives before they plateau, so steady state is around week three or four. Raising the dose in week two because nothing is happening usually just overshoots by the time levels level off.
How do I know if the dose is right?+
IGF-1 drawn mid-week between injections is the only practical marker. Sleep quality and water retention track exposure loosely, but people routinely find their IGF-1 is either barely moved or well above the reference range when they finally test.
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 — J Clin Endocrinol Metab (2006) PMID 16352683
- 2.Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog — J Clin Endocrinol Metab (2006) PMID 17018654
- 3.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 — Endocrinology (2005) PMID 15817669
More gh secretagogues
CJC-1295 no-DAC
Short-acting GHRH fragment that sharpens one GH pulse, almost always run with a GHRP.
100 mcg · 1-3x daily
GHRP-2
Potent, well-studied GHRP with a bigger pulse than ipamorelin and more cortisol.
100 mcg · 2-3x daily
GHRP-6
The original GHRP: solid GH release and the strongest hunger response of the group.
100 mcg · 2-3x daily
Hexarelin
The most potent GHRP, and the fastest to stop working if you run it continuously.
100 mcg · 1-2x daily