Last updated 2026-07-26
TL;DR
CJC-1295 with DAC is a growth-hormone-releasing hormone analogue chemically linked to a fatty acid (DAC, Drug Affinity Complex) that binds serum albumin, extending its half-life to roughly 6-8 days versus about 30 minutes without DAC. One published human trial found sustained GH and IGF-1 elevation over weeks. It is not FDA-approved for any use and is sold only as a research chemical.
What is CJC-1295 with DAC, exactly?
CJC-1295 is a synthetic analogue of growth-hormone-releasing hormone (GHRH), built from the first 29 amino acids of native GHRH with four substitutions that resist enzymatic breakdown [1]. The "with DAC" version adds a Drug Affinity Complex, a maleimide-linked fatty acid chain grafted onto the peptide's lysine residue. That fatty tail lets the molecule bind covalently to circulating albumin once injected, and albumin has a very long residence time in blood. That's the whole trick. Without DAC, the same core peptide (sometimes called CJC-1295 without DAC, or sold under the name Mod GRF 1-29) gets cleared in about 30 minutes [1]. With DAC attached, the terminal half-life stretches to somewhere between 5.8 and 8.1 days in the pharmacokinetic data reported by the compound's originating research group [1][2]. That's roughly a 300-fold difference in how long the molecule circulates in usable form. Both versions work on the same receptor, the GHRH receptor on pituitary somatotrophs, and both push the pituitary to release more growth hormone in a pulsatile pattern rather than dumping GH all at once. The difference is entirely about how long the drug stays around to keep nudging that pulse. For a side-by-side comparison of dosing patterns, injection frequency, and practical tradeoffs between the two forms, see cjc 1295 dac vs no dac.
How does the DAC modification actually extend half-life?
The DAC technology was developed by ConjuChem and later licensed out; it's the same albumin-binding chemistry used in a handful of other long-acting peptide candidates from that era [2]. The maleimide group on the fatty acid side chain reacts specifically with a free cysteine on albumin (Cys34), forming a stable covalent bond within minutes of injection. Once bound, the peptide essentially rides along with albumin through circulation. Albumin itself has a serum half-life measured in weeks. The conjugated peptide inherits a large chunk of that longevity, though it's not identical, because the peptide portion still gets degraded by proteases over time even while attached. The practical result, per the pharmacokinetic modeling in the original human trial, is a terminal elimination half-life of 5.8 to 8.1 days depending on dose, with GH and IGF-1 levels staying measurably elevated for at least 6 days after a single injection [1]. That single number is the whole reason this version exists: it converts a peptide that would need multiple daily injections into something dosed weekly or less often, at least in theory.
What does the human study actually show?
There's one frequently cited human trial, published in the Journal of Clinical Endocrinology & Metabolism in 2006, led by researchers including some of the peptide's original developers [1]. It tested single and multiple doses of CJC-1295 (with DAC) in healthy adults. Key findings reported in that paper: a single subcutaneous dose produced a dose-dependent increase in GH, with mean GH levels increased 2 to 10-fold depending on dose, and IGF-1 levels increased by 1.5 to 3-fold and sustained for 6 to 9 days after just one injection [1]. In the multiple-dose portion, participants got weekly or twice-weekly injections over 20 to 28 days, and IGF-1 stayed elevated above baseline for the entire dosing period without any obvious drop in response over time (no acute tachyphylaxis) [1]. That's genuinely useful data on mechanism and duration. It is also, as far as public literature goes, close to the entirety of the controlled human evidence base for this specific molecule. There isn't a large randomized trial measuring body composition, strength, sleep quality, or any downstream outcome bodybuilders actually care about. The 2006 paper measured hormone levels, not muscle gained or fat lost. Everything past that (protocols claiming specific fat-loss percentages, stacking ratios, "pulse versus constant elevation" theories) comes from forum reports and anecdote, not from published trials. Treat that material as folklore, not evidence, no matter how confidently it's written.
Is CJC-1295 with DAC FDA-approved or legal to buy for personal use?
No. CJC-1295, with or without DAC, has no FDA approval for any human indication. It is not a prescription drug and it is not an approved dietary supplement. In practice it is sold as a research chemical labeled "not for human consumption," which is the same legal framing used across the peptide research-chemical market. The FDA's guidance on bulk drug substances nominated for compounding lays out the case-by-case review process outsourcing facilities must go through before a substance can be used in compounded drugs, and unapproved GHRH-analogue peptides generally have not cleared that bar for the 503B bulk substances list [3]. Growth hormone itself, separately, is a controlled substance in most contexts and its non-prescribed distribution carries specific federal penalties under 21 U.S.C. § 333(e), which addresses unlawful distribution of human growth hormone [4]. CJC-1295 is not GH itself, it's a GHRH analogue that stimulates the body's own GH release, so it sits in a legal gray zone rather than falling directly under that GH-specific statute, but the regulatory posture toward unapproved injectable hormone-axis peptides generally is that they aren't legal for over-the-counter human use. Anyone considering this compound should understand they're in research-chemical territory, not approved-medicine territory. That changes what oversight, purity testing, and legal protection actually exist.
Why is CJC-1295 with DAC usually paired with ipamorelin?
The rationale is mechanistic, not a proven clinical outcome. CJC-1295 (with or without DAC) works on the GHRH receptor. Ipamorelin is a separate class of molecule, a ghrelin-receptor agonist (a GH secretagogue in the growth hormone secretagogue receptor family), and it stimulates GH release through a different pathway [5]. Because the two receptors sit on the same somatotroph cells but trigger release through different signaling cascades, combining a GHRH analogue with a ghrelin-receptor agonist is a well-established pattern in GH-axis research generally: GHRH analogues increase the amplitude of GH pulses, ghrelin-mimetics can increase pulse frequency and also blunt somatostatin's inhibitory tone. That combination principle is documented in endocrinology literature on GH secretagogues broadly [5], and it's the actual basis for pairing these two compounds. What's not established: that CJC-1295 with DAC plus ipamorelin produces a meaningfully different or better outcome than either compound alone in humans, at defined doses, over a defined period, with measured body-composition or health endpoints. Nobody has published that trial. The pairing is a reasonable extrapolation from receptor pharmacology, not a settled clinical result. If you see claims of combined effects backed only by a forum thread, that's the gap between mechanism and evidence. Ipamorelin itself has a short half-life (roughly 2 hours in early pharmacological characterization work), which is part of the logical fit: a long-acting GHRH-DAC background dose paired with a short-acting ghrelin-mimetic taken around specific times (often bedtime, to align with natural GH pulsatility) [5].
How is CJC-1295 with DAC dosed in research settings, and how does that differ from no-DAC protocols?
In the 2006 human trial, doses tested ranged up to 250 to 300 mcg/kg in some single-dose cohorts, with multiple-dose regimens using doses in the same general range delivered weekly or twice weekly over the 20 to 28 day study period [1]. Those are research-trial doses in a controlled setting, not a consumer dosing chart, and body-weight-scaled dosing in a clinical trial is not the same thing as fixed microgram amounts sold in research-chemical vials. The practical distinction that matters most: because DAC extends the half-life to days rather than minutes, dosing frequency in research use is typically far less often, sometimes once or twice weekly, whereas no-DAC CJC-1295 (Mod GRF 1-29) needs multiple daily doses to maintain any elevation, given its roughly 30-minute half-life [1]. That's the entire reason someone would choose the DAC version over the non-DAC version: convenience of injection frequency, traded against a flatter, more sustained hormone elevation versus a sharper pulse. For a full breakdown of dosing math, reconstitution, and how frequency schedules are typically calculated in research contexts, see cjc 1295 dosage and the cjc-1295 dac dosage calculator. Neither of those resources, nor this one, constitutes medical dosing advice, since no approved human dose exists.
What side effects and safety signals have been reported?
In the 2006 trial, reported adverse events were generally mild and consistent with what's seen with other GH-axis stimulating agents: injection site reactions, flushing, and some reports of headache [1]. That trial was short in duration (weeks, not months or years) and small in size, so it cannot rule out rarer or longer-term effects. Broader concerns that apply to sustained GH/IGF-1 elevation generally, based on endocrinology literature on growth hormone physiology rather than this specific peptide, include potential effects on insulin sensitivity, fluid retention, and joint discomfort, all recognized effects of elevated GH exposure in conditions like acromegaly [5]. Because CJC-1295 with DAC is specifically designed to keep IGF-1 elevated for days at a stretch rather than mimicking a natural pulsatile pattern, some researchers have raised theoretical concern about whether that sustained, non-pulsatile elevation carries different long-term risk than natural GH pulses. This hasn't been directly studied for this compound over a long duration. For a fuller rundown of documented and theoretical side effects, see cjc 1295 side effects.
How does CJC-1295 with DAC compare to CJC-1295 without DAC?
| Feature | CJC-1295 with DAC | CJC-1295 without DAC (Mod GRF 1-29) | |
|---|---|---|---|
| Half-life | 5.8 to 8.1 days [1] | Approximately 30 minutes [1] | |
| Typical research dosing frequency | Weekly to twice weekly | Multiple times daily | |
| GH release pattern | Sustained, flatter elevation | Sharper, more pulsatile | |
| Human trial data | One published PK/PD study, JCEM 2006 [1] | Studied primarily as GHRH(1-29) analogue class, less DAC-specific human data | |
| Molecular addition | Albumin-binding fatty acid (DAC) | None | The core peptide sequence is functionally similar between the two; the difference is entirely the DAC tail and what it does to circulation time. Neither is FDA-approved. For readers deciding between the two, the deeper comparison, including cost-per-week tradeoffs and injection burden, lives at cjc 1295 dac vs no dac. |
What does CJC-1295 do to GH and IGF-1 levels, in plain terms?
It raises both, and the DAC version keeps them raised longer than a single shot of most other GH secretagogues could manage. In the 2006 trial, a single dose of CJC-1295 with DAC produced GH increases described as several-fold above baseline (ranging roughly 2 to 10-fold across the dose range tested) and sustained IGF-1 elevation of about 1.5 to 3-fold baseline for 6 to 9 days after just one injection [1]. Over multiple weekly doses across the trial's 20 to 28 day period, mean IGF-1 levels stayed elevated throughout, which the authors interpreted as evidence the compound doesn't lose effect quickly with repeated dosing, at least across that short window [1]. That's a meaningfully different picture from a peptide you'd need to inject two or three times a day just to keep any signal going. What that data does not show is anything about downstream effects like lean mass, strength, recovery time, or fat loss, because the trial wasn't designed to measure those things. IGF-1 elevation is a biomarker, not a training outcome.
Where does the source material and evidence base come from, and what's still missing?
The core pharmacokinetic and safety data on CJC-1295 with DAC traces back almost entirely to one published trial: Teichman et al., 2006, in the Journal of Clinical Endocrinology & Metabolism [1]. That paper is legitimate peer-reviewed research and it's the single best primary source anyone can point to for this compound's actual behavior in the human body. What's missing is everything that would normally follow a promising phase 1/2 result: larger randomized trials, longer follow-up, dose-response studies in specific populations, and any trial measuring functional outcomes rather than hormone levels. As far as public record shows, CJC-1295 (with or without DAC) never advanced through that pipeline toward FDA approval, and it isn't currently listed as an active investigational new drug program in public FDA trial databases. That gap between one solid mechanistic trial and an approved, well-characterized therapeutic is exactly where most of the bodybuilding-forum confidence outruns the actual science. If you read a claim about CJC-1295 with DAC's effect on fat loss percentage, sleep architecture, or long-term safety over months of use, ask what study it's citing. Usually the honest answer is: none. For the broader mechanism-level background on the compound as a class, see cjc 1295.
If someone wants to research this compound, what should they actually look for in a source?
Because CJC-1295 with DAC is unregulated as a consumer product, quality control is the buyer's problem entirely, not a pharmacy's or the FDA's. Third-party certificates of analysis (COAs) confirming peptide identity and purity, clear sourcing of the actual synthesis lab, and transparent batch testing are the baseline things to check before anything else. CJC-1295 Co reviews providers against those criteria and points researchers toward a provider-reviewed sourcing path, with fulfillment through Tailor Made Compounding, a licensed pharmacy partner, rather than unverified individual sellers. That's a sourcing-quality distinction, not a claim that this makes the compound approved, safe for self-administration, or effective for any specific outcome. None of that changes based on who fills the vial. For a broader look at how to evaluate vendors, pricing, and what "provider-reviewed" actually means in practice, see cjc 1295 for sale.
Frequently asked questions
What is the difference between CJC-1295 and CJC-1295 with DAC?
CJC-1295 without DAC (often sold as Mod GRF 1-29) has a half-life of about 30 minutes and needs multiple daily doses. CJC-1295 with DAC has a fatty acid chain that binds serum albumin, extending its half-life to 5.8-8.1 days, so it's dosed weekly or twice weekly in research protocols instead [1].
How long does CJC-1295 with DAC stay in your system?
Published pharmacokinetic data puts the terminal half-life at 5.8 to 8.1 days, with GH and IGF-1 levels measurably elevated for at least 6 to 9 days after a single injection in the 2006 human trial [1]. That's the whole point of the DAC modification: extended circulation time via albumin binding.
Is CJC-1295 with DAC FDA-approved?
No. CJC-1295, with or without DAC, has no FDA approval for any human use. It's sold as a research chemical labeled not for human consumption, and it doesn't appear as an approved drug product in FDA's public drug databases.
Why do people combine CJC-1295 with DAC and ipamorelin?
CJC-1295 acts on the GHRH receptor while ipamorelin acts on the separate ghrelin/GH secretagogue receptor, so the combination targets two different GH-release pathways on the same pituitary cells [5]. This is a reasonable pharmacological rationale, but no published human trial has tested the combination's effect on body composition or long-term outcomes specifically.
What did the 2006 CJC-1295 human study actually find?
Published in the Journal of Clinical Endocrinology & Metabolism, it found dose-dependent GH increases (roughly 2-10 fold) and sustained IGF-1 elevation (1.5-3 fold baseline) lasting 6-9 days after a single dose, with elevation maintained across a 20-28 day multiple-dose regimen without an obvious drop in effect [1].
What are the known side effects of CJC-1295 with DAC?
The 2006 trial reported mostly mild effects: injection site reactions, flushing, and some headache reports [1]. The trial was short and small, so longer-term or rarer effects aren't well characterized. Theoretical concerns tied to sustained GH/IGF-1 elevation, including effects on insulin sensitivity and fluid retention, come from broader GH physiology literature, not CJC-1295-specific long-term studies.
How often do you inject CJC-1295 with DAC versus without DAC?
With DAC, research protocols generally used weekly to twice-weekly dosing because of the extended half-life. Without DAC, the roughly 30-minute half-life means multiple injections per day would be needed to maintain any consistent elevation, which is the main practical tradeoff between the two forms [1].
Does CJC-1295 with DAC cause a flatter or more natural GH release pattern?
It produces a more sustained, flatter elevation of GH and IGF-1 over days, rather than the sharp, short pulses seen with no-DAC CJC-1295 or with ghrelin-mimetics like ipamorelin. Whether that flatter pattern is more or less desirable physiologically than natural pulsatility hasn't been directly studied long-term for this compound.
Is it legal to buy CJC-1295 with DAC for personal use?
It's sold as a research chemical, not an approved drug, which puts it in a legal gray zone rather than clearly permitted for personal human use. Growth hormone itself carries specific federal distribution restrictions under 21 U.S.C. § 333(e), though CJC-1295 as a GHRH analogue is a distinct substance from GH itself [4].
What dose of CJC-1295 with DAC was used in clinical research?
The 2006 human trial tested single doses up to roughly 250-300 mcg/kg in some cohorts, with multiple-dose regimens using comparable per-dose amounts delivered weekly or twice weekly over 20-28 days [1]. These are controlled trial doses, not a validated consumer dosing standard.
Can CJC-1295 with DAC help with fat loss or muscle gain?
No published human trial has measured fat loss, muscle gain, strength, or body composition outcomes for CJC-1295 with DAC. The available evidence covers GH and IGF-1 blood levels only. Claims about specific body-composition results come from anecdote, not from the peer-reviewed record [1].
What's the difference between CJC-1295 with DAC and ipamorelin alone?
CJC-1295 with DAC is a long-acting GHRH-receptor agonist dosed infrequently due to its multi-day half-life. Ipamorelin is a short-acting ghrelin-receptor agonist with a half-life of roughly 2 hours, typically dosed once or more daily. They act on different receptors, which is the pharmacological basis for stacking them [5].
Sources
- Journal of Clinical Endocrinology & Metabolism, Teichman et al. 2006: Half-life of 5.8-8.1 days, GH/IGF-1 fold increases, and sustained elevation over 20-28 days of dosing
- National Center for Biotechnology Information, PubChem - CJC-1295: Structural description of CJC-1295 and its albumin-binding DAC modification
- U.S. Code, 21 U.S.C. § 333(e): Federal penalties for unlawful distribution of human growth hormone
- Sigalos & Pastuszak, "The Safety and Efficacy of Growth Hormone Secretagogues," Sexual Medicine Reviews, NIH National Library of Medicine (PMC5039080): Ghrelin-receptor agonists like ipamorelin act through a distinct GH secretagogue receptor pathway from GHRH analogues
- National Cancer Institute / NIH, DailyMed label reference for Somatropin (recombinant human growth hormone) via NLM: Reference labeling for recombinant human growth hormone used for comparison of GH-axis effects and adverse event categories
- PubChem, National Center for Biotechnology Information - Ipamorelin: Structural classification of ipamorelin as a ghrelin receptor agonist and its pharmacological profile