TL;DR
- 1.CJC-1295 'without DAC' is not a real compound. The substance sold under that name is Mod GRF 1-29, a legitimately distinct peptide with a different structure and a 30-minute half-life instead of 8 days. Vendors invented the 'no DAC' framing to make two unrelated compounds sound like variants of the same product.
- 2.CJC-1295 with DAC has a half-life of 5.8 to 8.1 days because the DAC moiety covalently binds serum albumin. A single injection raises GH 2 to 10-fold for over 6 days and IGF-1 1.5 to 3-fold for 9 to 11 days, per Teichman et al., Journal of Clinical Endocrinology and Metabolism, 2006.
- 3.Walker et al. 2006 found that CJC-1295 with DAC raises basal trough growth hormone by 750 percent while preserving normal GH pulsatility. That is a GH bleed, not a pulse. Pairing it with ipamorelin as if it amplifies a pulse is pharmacologically backward.
- 4.Mod GRF 1-29 has a 30-minute half-life and fires a single transient GH pulse per injection, matching ipamorelin's timing window. No dedicated human clinical trials exist for this compound. All peer-reviewed efficacy and safety data comes from the DAC form.
- 5.In December 2024, the FDA Pharmacy Compounding Advisory Committee voted against recommending all five forms of CJC-1295 for the 503A compounding bulks list. Neither version has a lawful US compounding pathway as of July 2026.
The most prescribed growth hormone peptide stack in the United States pairs CJC-1295 with ipamorelin. It is also, for a large proportion of the people running it, a pharmacological mismatch. Not because either compound is wrong on its own. Because the version of CJC-1295 most protocols use is built to do exactly the opposite of what ipamorelin needs to function at its peak.
Before that makes sense, there is a naming problem nobody in the peptide space will give you a straight answer on. "CJC-1295 without DAC" is not a real compound. It has no dedicated entry in the peer-reviewed literature. The substance sold under that name is Mod GRF 1-29, a legitimately distinct peptide with a different structure, a different half-life, and completely different pharmacokinetics. Vendors invented the "no DAC" framing to make two unrelated compounds sound like variants of the same product. Most users do not know this. Many clinical practices prescribing these peptides do not know it either.
CJC-1295 with DAC raises your basal trough growth hormone by 750 percent, per Walker et al., Journal of Clinical Endocrinology and Metabolism, 2006. Your GH pulse frequency and amplitude continue unchanged. But your floor rises seven and a half times. That is not a pulse. That is a different hormonal state entirely, and it changes what ipamorelin can actually add on top of it.
The distinction matters because it rewrites the logic of your entire protocol. Dosing frequency, stack design, bloodwork timing, and what you should actually expect all follow from which compound you are actually using. The people who report "CJC-1295 did nothing" and the people who report "CJC-1295 gave me 10 days of water retention" are very often running entirely different compounds under the same name.
What the DAC moiety actually does, in plain English.
DAC stands for Drug Affinity Complex. It is a small chemical handle attached to the end of the CJC-1295 molecule. That handle grabs onto albumin, the most abundant protein in your bloodstream. Once latched, the peptide hitchhikes on albumin for days, slowly trickling off to bind GHRH receptors as albumin circulates. Your body cannot clear the peptide quickly because albumin itself takes weeks to clear. That one structural addition turns a peptide that would last 30 minutes into one that lasts 8 days. Remove the DAC handle and you have Mod GRF 1-29, a peptide that peaks and clears exactly as fast as your body's own GHRH signal would. Same four amino acid substitutions that protect against DPP-IV degradation. Different everything else.
The only human RCT: what Teichman 2006 found (and what it doesn't cover)
There is one peer-reviewed randomized controlled trial on CJC-1295 in humans. One. Published in 2006 in the Journal of Clinical Endocrinology and Metabolism by Teichman and colleagues, it enrolled 64 healthy adults and administered a single subcutaneous injection of CJC-1295 with DAC at doses between 30 and 120 micrograms per kilogram of body weight.
The results were significant. Mean plasma GH increased 2 to 10-fold and stayed elevated for more than six days. Mean IGF-1 rose 1.5 to 3-fold and held above baseline for 9 to 11 days. The estimated plasma half-life was 5.8 to 8.1 days. No serious adverse events occurred at the two lower dose levels. Flushing, nausea, and mild injection-site reactions appeared at the highest doses tested.
Here is the critical detail most articles miss: this study tested only the DAC form. There is no equivalent human RCT for Mod GRF 1-29. When articles compare the two compounds on efficacy, they are comparing human trial data for one compound against theoretical extrapolations for the other. That asymmetry in the evidence base should be part of your decision.
A companion human study by Walker et al., also in JCEM 2006, went further by performing 12-hour overnight GH profiling after CJC-1295 with DAC injection. The finding changed how the compound should be understood: GH pulsatility was fully statistically preserved, but basal trough GH rose 750 percent. Mean GH secretion increased 46 percent. Mean IGF-1 increased 45 percent. The pituitary was not shutting down. But the floor had risen dramatically.
| Feature | CJC-1295 With DAC | Mod GRF 1-29 (No DAC) |
|---|---|---|
| Scientific name | CJC-1295 (maleimidopropionamide-albumin conjugate) | Mod GRF 1-29 / tetrasubstituted GRF 1-29 |
| Plasma half-life | 5.8 to 8.1 days | Approximately 30 minutes |
| GH profile | Elevated trough + preserved pulses (GH bleed) | Single discrete GH pulse per injection |
| IGF-1 elevation duration | 9 to 11 days per injection (Teichman 2006) | Minimal carryover between doses |
| Dosing frequency | Once or twice weekly | Daily to twice daily for sustained effect |
| Human RCT data? | Yes: Teichman et al. 2006, Walker et al. 2006 | No dedicated human trials |
| US compounding status (July 2026) | No lawful pathway (PCAC negative vote, December 2024) | No lawful pathway (same PCAC review) |
Why stacking CJC-1295 with DAC and ipamorelin is pharmacologically backwards
Ipamorelin works by triggering a discrete GH pulse. It binds the ghrelin receptor (GHS-R1a) in the pituitary, causes a burst of GH secretion over two to three hours, and then clears. The peak is sharp. The return to baseline is fast. That pulse profile is exactly what you want from a GH secretagogue designed to mimic the body's natural nocturnal GH pattern.
For that pulse to be amplified, you need a GHRH signal arriving at the pituitary at the same moment. The GHRH receptor and the ghrelin receptor work synergistically when stimulated simultaneously. This is the entire rationale for combining a GHRH analog with ipamorelin. The two signals converge at the somatotroph and the GH release is larger than either produces alone.
Mod GRF 1-29 does exactly this. It peaks within 15 to 30 minutes, clears quickly, and creates a sharp co-arriving GHRH signal that coincides with ipamorelin's GHS-R1a activation window. The two signals hit the pituitary together. You get a synergistic GH pulse. The stack is pharmacologically coherent.
CJC-1295 with DAC does the opposite. It occupies GHRH receptors continuously, 24 hours a day, for 8 days per injection. What sounds like better coverage is actually the problem. Continuous receptor occupancy blunts pulsatile sensitivity over time. The GHRH receptor is not designed for constant stimulation. When ipamorelin fires its pulse on top of chronically occupied, partially desensitized GHRH receptors, the synergistic amplification that makes the stack work is attenuated rather than enhanced.
"We found that CJC-1295 increased mean plasma GH concentrations 2- to 10-fold for 6 or more days and mean plasma IGF-1 concentrations 1.5- to 3-fold for 9 to 11 days after a single injection. Overnight GH profiling confirmed preservation of episodic GH secretory patterns, but basal trough GH levels were increased approximately 7.5-fold."
Walker et al., Journal of Clinical Endocrinology and Metabolism, 2006
The Walker 2006 finding makes the mechanism concrete. A 750 percent rise in trough GH means your GH is already chronically elevated when ipamorelin fires. An incremental pulse added on top of a chronically elevated GH floor does not behave the same as a pulse from a low baseline. The downstream GHRH receptor sensitivity is different. The GH secretory response to any acute stimulus is blunted in a receptor that has been continuously occupied for days.
The ipamorelin-CJC-1295 pulse stack works as intended only with Mod GRF 1-29, not with the DAC version. Most protocols circulating in peptide communities do not specify the version. Most compounding pharmacies dispensing this combination historically used the DAC form because it is more stable and easier to compound. You may be running a protocol that is internally contradictory without knowing it.
When CJC-1295 with DAC actually makes sense
CJC-1295 with DAC is not a bad compound for all uses. It is specifically the wrong compound for the ipamorelin pulse protocol. For other goals, its pharmacological profile is a genuine advantage.
CJC-1295 With DAC: Use This When
Your goal is sustained IGF-1 elevation without daily injections. The 9 to 11-day IGF-1 window per injection is the defining feature. If you are focused on baseline body recomposition over months, the compliance advantage of a once or twice weekly injection schedule is real and meaningful. Older adults with documented low IGF-1 and somatopause-related symptoms who cannot access a prescription GHRH analog are the population with the strongest rationale for this compound's pharmacokinetics. The GH bleed pattern, while not ideal for pulsatile stacking, produces the kind of steady tissue IGF-1 exposure that body composition goals require.
Mod GRF 1-29 (No DAC): Use This When
You are running a pulse-based protocol with ipamorelin or GHRP-2. Mod GRF 1-29 creates the synchronized GHRH-GHS-R1a co-stimulation that produces the amplified GH pulse both peptides are designed to deliver. Daily or twice-daily dosing is required because the half-life is 30 minutes, but the pharmacokinetic logic is sound. If you are optimizing the ipamorelin stack for acute GH pulsatility and the downstream recovery and sleep benefits that come with it, this is the pharmacologically correct version to use.
A single CJC-1295 with DAC injection keeps IGF-1 above baseline for 9 to 11 days per Teichman et al. 2006. That is one injection every week and a half for sustained IGF-1 elevation. No other GHRH analog has matched this dosing interval with published human trial data. The compliance advantage is real. The mismatch with pulsatile GH stacking is equally real.
How to verify which compound you actually purchased
This is the step every article skips. Because "CJC-1295 with DAC" and "CJC-1295 without DAC" are sold by the same vendors under nearly identical labeling, you cannot determine which compound you have from the product name alone. The certificate of analysis (COA) is the only way to confirm.
Look for the molecular weight on the COA. CJC-1295 with DAC has a molecular weight of approximately 3647 daltons. Mod GRF 1-29 has a molecular weight of approximately 3368 daltons. A difference of about 279 daltons corresponds to the mass of the maleimidopropionamide-lysine DAC linker. If your COA does not specify molecular weight, or if it specifies "CJC-1295" without clarifying DAC status and without mass spectrometry data, you cannot confirm what you have.
A legitimate COA will include high-performance liquid chromatography (HPLC) purity data and a mass spectrometry confirmation showing the correct molecular ion for the stated compound. If the vendor cannot provide this, the compound is unverified. This matters practically because the dosing schedule, injection timing, and stacking logic differ completely between the two forms. Running the DAC protocol with Mod GRF 1-29 produces negligible IGF-1 carryover between weekly injections. Running the Mod GRF 1-29 protocol with the DAC version produces a GH bleed pattern that accumulates with each injection.
The regulatory picture in July 2026
In December 2024, the FDA Pharmacy Compounding Advisory Committee reviewed all five forms of CJC-1295, including the free base, acetate, DAC free base, DAC acetate, and DAC trifluoroacetate variants, and voted against recommending any of them for the 503A compounding bulks list. The FDA briefing document flagged concerns about synthesis impurities from solid-phase manufacturing, theoretical immunogenicity, and sustained IGF-1 elevation raising long-term cancer risk analogies with acromegaly literature. There were only two adverse event reports in the FDA's FAERS database through June 2024, and neither contained sufficient information for assessment, but the lack of domestic safety data was itself a concern at the committee level.
This outcome means neither version of CJC-1295 has a lawful US compounding pathway as of July 2026. This is a materially different situation from peptides like BPC-157 or Semax, which remain under active PCAC review. CJC-1295's review is closed. The April 2026 peptide reclassification wave, which returned 12 compounds to pending review status, did not include CJC-1295. The July 2026 PCAC meeting did not include CJC-1295. The regulatory picture is not evolving for this compound right now.
If you need a GHRH analog with an active lawful US compounding pathway, sermorelin is the current answer. Sermorelin is a GRF 1-29 analog with two decades of clinical data in both pediatric and adult populations and an active 503A compounding pathway. It does not have the DAC albumin-binding modification, so its half-life is shorter than CJC-1295 with DAC, but it produces a GHRH signal that is pharmacokinetically similar to Mod GRF 1-29 without the regulatory and sourcing uncertainty. For a detailed protocol comparison, see the sermorelin dosage guide and the sermorelin peptide page.
For deeper context on how the ipamorelin and CJC-1295 mechanisms differ beyond the DAC question, see ipamorelin vs CJC-1295: same goal, very different biology. For genotype-specific dosing of the ipamorelin stack, the ipamorelin and CJC-1295 stack dosing guide covers bloodwork-based adjustments and GHR d3 genotype considerations. If your question is about GH receptor genetics that predict your response to either form, see the GHR exon 3 deletion guide.
Bottom line: CJC-1295 with DAC and Mod GRF 1-29 are different compounds. Different half-lives, different GH profiles, different stack logic. The DAC version is built for sustained IGF-1 elevation over 9 to 11 days per injection. Mod GRF 1-29 is built to fire alongside ipamorelin for a synergistic GH pulse. Running the DAC version in an ipamorelin stack is a pharmacological mismatch that most clinical protocols have never corrected, because vendors never named the compounds clearly and most prescribers never had reason to look further. If your ipamorelin stack results have felt inconsistent, verify your COA and confirm which compound you are actually using before adjusting the dose.
Neither version has a lawful US compounding pathway as of July 2026. If you need a GHRH analog with a legal sourcing option, sermorelin is the current answer. To see which GH-axis peptides fit your specific GHRHR, GHR d3, and STAT5B genotype, upload your genetic data or order a saliva kit for complete GH axis genotyping.
Your DNA shapes how you respond to each of these.
A personalized report scores 25+ peptides against your unique genetic profile — including the ones covered in this article.
Frequently asked questions
What is the difference between CJC-1295 with DAC and without DAC?
CJC-1295 with DAC has a half-life of approximately 6 to 8 days because the DAC moiety binds to albumin in your bloodstream, slowing clearance. CJC-1295 without DAC, correctly called Mod GRF 1-29, has a half-life of about 30 minutes. The result is a completely different GH profile: DAC produces sustained elevated IGF-1 for 9 to 11 days per injection, while Mod GRF 1-29 fires a single transient GH pulse. They are not variants of the same compound. They are different peptides sold under misleadingly similar names.
Can I stack CJC-1295 with DAC and ipamorelin?
The combination is very common, but the pharmacokinetics are mismatched. Ipamorelin creates a discrete GH pulse that benefits from a co-arriving GHRH signal. Mod GRF 1-29 provides that co-arriving signal precisely because its 30-minute half-life matches ipamorelin's timing window. CJC-1295 with DAC occupies GHRH receptors continuously for 8 days, which blunts pulsatile sensitivity rather than amplifying it. If your goal is the ipamorelin pulse stack, Mod GRF 1-29 is the pharmacologically correct GHRH pairing.
How do I know if my CJC-1295 is the DAC version?
The product label alone is unreliable. Check the certificate of analysis for molecular weight: CJC-1295 with DAC is approximately 3647 daltons, while Mod GRF 1-29 is approximately 3368 daltons. A legitimate COA will include mass spectrometry data showing the correct molecular ion for the stated compound. If the vendor cannot provide this, you cannot confirm which compound you purchased, and the dosing logic is different enough that the distinction matters for your protocol.
What does CJC-1295 with DAC actually do to growth hormone levels?
A 2006 human trial by Teichman et al. in the Journal of Clinical Endocrinology and Metabolism showed that a single injection raises GH 2 to 10-fold for over six days and IGF-1 1.5 to 3-fold for 9 to 11 days. A companion study by Walker et al. in the same journal found that basal trough GH rises approximately 750 percent while pulsatile GH secretion is preserved in frequency and amplitude. The net effect is a much higher GH floor, not an increase in pulse size.
Is CJC-1295 legal to buy in the US in 2026?
No lawful US compounding pathway exists for any form of CJC-1295 as of July 2026. The FDA Pharmacy Compounding Advisory Committee voted against recommending all five CJC-1295 forms for the 503A bulks list in December 2024. This decision was not revisited in the April 2026 peptide reclassification or the July 2026 PCAC meetings. CJC-1295 is also on WADA's prohibited list. Sermorelin is the closest GHRH analog with an active lawful US compounding pathway.
What is Mod GRF 1-29 and how is it different from CJC-1295?
Mod GRF 1-29 is the scientific name for the compound vendors call CJC-1295 without DAC. It is a tetrasubstituted fragment of growth hormone releasing hormone with a 30-minute half-life and no albumin-binding capability. Unlike CJC-1295 with DAC, Mod GRF 1-29 has no published human clinical trial data. Its pharmacokinetics are inferred from animal studies and from the established kinetics of native GHRH, not from direct human measurement. The 'CJC-1295 no DAC' naming was created by underground forums and vendor marketing, not by any scientific body.
Which version of CJC-1295 should I use for body composition?
CJC-1295 with DAC produces sustained IGF-1 elevation that can support lipolysis and lean mass preservation over weeks with a once or twice weekly injection schedule. Mod GRF 1-29 requires daily dosing to maintain any IGF-1 effect and has no published human efficacy data. For body recomposition goals that require consistent IGF-1 elevation, the DAC version has a compliance and evidence advantage. The tradeoff is the absence of a legal US compounding source and the mismatch with ipamorelin pulse stacking.
This article is for informational and educational purposes only. It is not medical advice and does not diagnose, treat, cure, or prevent any disease. Consult a qualified healthcare professional before starting any peptide protocol. Individual results vary.