CJC-1295 No DAC: What Distinguishes It from the DAC Construct
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“CJC-1295 no DAC” is commonly a catalog name for Modified GRF (1-29), a short GHRH analog that lacks the albumin-binding element found in CJC-1295 with DAC. Without that binding domain, it clears the bloodstream fast, producing brief, pulsatile growth hormone releases rather than a sustained signal. This distinction matters because most published pharmacokinetic and pharmacodynamic data on “CJC-1295” describe the DAC construct specifically.
No-DAC material: short half-life, pulsatile GH pattern, limited direct human PK/PD data
DAC construct: multi-day half-life, sustained IGF-I elevation, backed by peer-reviewed human trials
The naming overlap between the two is the single biggest source of confusion in supplier literature
Key Takeaways
CJC-1295 no DAC (Modified GRF 1-29) lacks the albumin-binding domain that gives the DAC construct its multi-day half-life, so pulsatile-response research protocols cannot borrow endpoints built for sustained-exposure studies.
Point | Details |
Two distinct constructs | Modified GRF (1-29) and CJC-1295 with DAC have different sequences and pharmacokinetics despite overlapping catalog names. |
DAC evidence is construct-specific | Teichman et al.'s multi-day GH and IGF-I data apply to the DAC construct, not automatically to no-DAC material. |
Sampling strategy must match the analog | Pulsatile no-DAC responses need frequent draws; sustained DAC exposure suits multi-day IGF-I AUC tracking. |
Anti-doping and regulatory status apply broadly | Both constructs are WADA-monitored and lack FDA approval for human use. |
Verify identity before use | Rapidcorebio provides lot-matched COAs with HPLC/MS purity data for research-grade CJC-1295 orders. |
This article is general information, not a substitute for advice from a qualified doctor. Consult a qualified healthcare professional about your own circumstances before acting on anything here.
Table of Contents
What Is CJC-1295 No DAC? Naming and Molecular Identity
Modified GRF (1-29) is the peptide most vendors mean when they list “CJC-1295 no DAC.” It’s a 29-amino-acid analog of growth hormone-releasing hormone with four stabilizing substitutions but no attached drug affinity complex (DAC). CJC-1295 with DAC, by contrast, carries a maleimide-linked lysine that binds covalently to circulating albumin, a modification that fundamentally changes how long the molecule stays active.
Why does the label matter so much? Because “CJC-1295” alone has been used loosely across research forums and catalogs to refer to either construct.
Modified GRF (1-29): also sold as “Mod GRF 1-29,” “GRF 1-29 modified,” or “CJC-1295 no DAC”
CJC-1295 with DAC: sometimes just called “CJC-1295” without qualification
Sequence, CAS number, and PubChem identifiers differ between the two, and a batch certificate of analysis should confirm which one a supplier actually shipped
DAC vs No-DAC: Half-Life, Exposure Pattern, and Practical Implications
The pharmacokinetic gap between these two constructs isn’t subtle. Peer-reviewed human data on the DAC construct describe a half-life in the range of roughly 5.8 to 9.2 days, with growth hormone elevations lasting up to six days and IGF-I increases persisting as long as two weeks after a single dose. No-DAC material behaves nothing like that.
DAC construct: sustained exposure supports long-interval sampling and IGF-I area-under-curve analysis
No-DAC material: rapid clearance means researchers need frequent, tightly spaced sampling to catch each GH pulse
Neither profile is directly interchangeable with the other when designing an experiment
This changes what a study can even measure. A protocol built around the DAC construct’s sustained IGF-I signal will miss the point entirely if applied to no-DAC material, where the interesting data live in the shape and frequency of individual GH pulses, not a smooth curve.
GHRH Receptor Activation and the GH/IGF-I Cascade
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Both constructs work through the same receptor. They bind the GHRH receptor on pituitary somatotrophs, triggering a cyclic AMP cascade that stimulates the pulsatile release of growth hormone from the pituitary. GH then travels to the liver, where it drives IGF-I production, the downstream marker researchers typically track as a proxy for sustained GHRH receptor stimulation.
The difference is what happens after that initial trigger.
No-DAC material activates the receptor and clears quickly, producing a single, short GH pulse
The DAC construct’s covalent albumin binding keeps it circulating for days, generating repeated stimulation
That prolonged exposure is what produces the fold-change data documented in human trials
Statistic callout: Human DAC-construct data reported mean GH increases of 2 to 10 times baseline sustained for up to six days, and IGF-I increases of 1.5 to 3 times baseline lasting as long as 14 days after single dosing in healthy adults. No comparable human dataset exists for the no-DAC material at this scale.
Primary Evidence: Strong Data for DAC, a Thinner Record for No-DAC
The Teichman et al. trial remains the primary human PK/PD record for CJC-1295, and it tested the DAC construct exclusively. Preclinical work backs the mechanism further: a study in GHRH knockout mice found that a long-acting, albumin-binding CJC-1295 construct normalized growth after once-daily dosing, supporting the idea that covalent albumin binding is what drives prolonged exposure.
None of that evidence transfers automatically to no-DAC material. The mechanism that produces multi-day GH and IGF-I elevation is the albumin-binding domain itself, and no-DAC material doesn’t have one.
Evidence guides on the topic are blunt about this gap: the name “CJC-1295” in vendor catalogs is used loosely, and the DAC group is integral to the exact construct tested in human trials. Mapping a supplier’s “no DAC” label onto DAC-construct study results is not a supported inference.
Researchers publishing or procuring material should require explicit construct identification, matched against sequence data and a batch-specific COA, in every methods section and purchase record. Assuming equivalence because two products share part of a name is how experimental conclusions go wrong.
Safety Signals, Anti-Doping Status, and Regulatory Standing
Reported acute effects associated with GHRH analogs in general include injection-site reactions, flushing, headache, and transient changes in blood glucose, though the strength of that evidence varies widely between formal trial reporting and anecdotal accounts. Neither construct has been evaluated in a large-scale safety trial specific to the no-DAC form.
Injection-site irritation and flushing appear most frequently in available reports
Headache and mild dizziness are reported less consistently, mostly outside controlled trials
Growth-hormone axis peptides, including CJC-1295 variants, are monitored and prohibited under the WADA Prohibited List, a relevant consideration for anyone in competitive sport
Neither the DAC construct nor Modified GRF (1-29) carries FDA approval for human use, and FDA substance registry records track the two moieties as distinct entries
Research-Use Disclaimer and Quality Controls to Demand
Every peptide discussed here is sold and described strictly as a research compound, not for human or animal use, diagnostic purposes, or consumption of any kind. Before using any batch in a study, confirm the following against the supplier’s documentation:
HPLC and mass spectrometry purity data specific to that lot
Endotoxin testing results and sterility notes
Lot-to-lot matching between the COA and the physical vial received
Storage conditions documented for stability over the study period
Pro Tip: Cross-check the sequence listed on the COA against the PubChem or FDA substance entry for the construct you intend to study, not just the product name on the label.
Designing Sampling and Endpoints for Short-Acting vs Long-Acting Analogs
Comparing a pulsatile analog against a sustained one demands different sampling logic, not just a different peptide.
Use frequent, closely spaced blood draws to capture GH pulsatility when studying no-DAC material, since a single pulse can resolve within an hour
Use multi-day sampling windows and IGF-I area-under-curve calculations when studying the DAC construct, matching the sustained exposure pattern reported in human trials
Add antibody monitoring and confirm assay sensitivity thresholds before finalizing a protocol, since low-amplitude pulses are easy to miss with an underpowered assay
Report material identity, lot number, COA data, and assay method in every publication so results can be mapped to the correct construct later
Why Precise Identity Still Drives Good Research
Getting the construct right isn’t a formality. It’s the difference between a dataset that means something and one that gets quietly retracted when someone notices the “CJC-1295” in the methods section was never specified as DAC or no-DAC. That ambiguity has already muddied enough forum discussion and marketing copy; peer-reviewed research doesn’t have room for it.
At Rapidcorebio, every batch ships with documentation built around that same standard, because a research program is only as reliable as the identity of what’s in the vial.
— Adrian K. Solis
Research-Grade CJC-1295 With Verified Documentation
Rapidcorebio’s advantage isn’t a lower price. It’s that every batch of research-grade CJC-1295 ships with a lot-matched certificate of analysis, so your methods section can cite exact purity data instead of a vague supplier claim.
Every peptide Rapidcorebio distributes is sold strictly for laboratory research and is not intended for human or animal use. Each listing links to third-party COA verification covering HPLC and mass spectrometry purity results, so you can confirm identity before the material ever enters a protocol. If you’re still mapping out sourcing standards for a study, the research handbook walks through how to read a COA line by line. Ready to source a verified batch? Check current CJC-1295 availability and request the lot-specific COA before you order.
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