What Is CJC-1295? (Same as CJC 1295 Peptide Explained)

The molecule you'll see written as 'CJC-1295', 'CJC 1295', or occasionally 'CJC1295' is chemically identical. The spacing and hyphenation are stylistic conventions, not structural distinctions. This isn't three different peptides. It's one compound: a 30-amino-acid synthetic analog of growth hormone-releasing hormone (GHRH) developed to resist enzymatic degradation that normally limits native GHRH to a half-life of fewer than seven minutes. Research published in the Journal of Clinical Endocrinology & Metabolism demonstrated that substituting four amino acids in the native GHRH sequence extended the bioactive half-life to approximately eight days when paired with Drug Affinity Complex (DAC), the albumin-binding moiety that keeps the peptide circulating rather than clearing through renal filtration.

Our team has worked with research institutions studying growth hormone secretagogues for over a decade. The confusion around CJC-1295 naming stems from one historical mistake: early suppliers mislabelled modified GRF(1-29). A structurally different peptide without DAC. As 'CJC-1295'. That error propagated through underground forums, research logs, and product catalogues for years. The result? Two peptides with overlapping nicknames but entirely different pharmacokinetic profiles.

What is CJC-1295, and is it the same as CJC 1295?

CJC-1295 and CJC 1295 refer to the same synthetic peptide analog of growth hormone-releasing hormone (GHRH). The naming variations (spacing, hyphenation) are stylistic only. The authentic compound contains 30 amino acids and includes Drug Affinity Complex (DAC), which extends its plasma half-life to approximately eight days by binding serum albumin. Modified GRF(1-29), often mislabelled as 'CJC-1295 no-DAC', is a structurally different peptide with a half-life of roughly 30 minutes and does not contain DAC.

The Direct Answer Block clarifies what most summaries skip: CJC-1295 exists in two commercially distinct forms. One with DAC (the original compound developed by ConjuChem Biotechnologies) and one without (modified GRF(1-29), which should never have been called CJC-1295 but frequently is). This matters because the pharmacokinetics differ by orders of magnitude: DAC-conjugated CJC-1295 produces sustained elevation in growth hormone and IGF-1 over days, while modified GRF(1-29) generates acute pulses lasting 90–120 minutes. Research protocols using these peptides are not interchangeable. This article covers the molecular structure of authentic CJC-1295, the DAC vs. no-DAC distinction, what each form does mechanistically, and why naming precision matters when sourcing research-grade peptides.

CJC-1295 Molecular Structure and Mechanism

Authentic CJC-1295 consists of a 30-amino-acid sequence with four strategic substitutions relative to native GHRH(1-29): Tyr1 → D-Ala2, Ala8 → Gln8, Ala15 → Leu15, and Met27 → Leu27. These changes block dipeptidyl peptidase-IV (DPP-IV) cleavage at the N-terminus. The primary degradation pathway that limits endogenous GHRH to a circulating half-life of under seven minutes. Without that enzymatic vulnerability, the peptide persists long enough to bind GHRH receptors on anterior pituitary somatotrophs repeatedly across multiple secretory cycles.

The Drug Affinity Complex (DAC) attached at the C-terminus is a maleimidoproprionic acid derivative that binds non-covalently to serum albumin. Albumin binding creates a depot effect: the peptide-albumin complex is too large for glomerular filtration, so renal clearance drops from minutes to days. Published pharmacokinetic studies show peak plasma concentration occurs 1–2 hours post-injection with sustained detectability for 6–8 days. Growth hormone pulses don't stop after a single secretory event. They continue as long as CJC-1295 remains bound to pituitary GHRH receptors, which is why IGF-1 elevation persists across the dosing interval rather than spiking and returning to baseline within hours.

Modified GRF(1-29). The peptide frequently mislabelled as 'CJC-1295 no-DAC'. Contains the same four amino acid substitutions but lacks the DAC moiety entirely. It's 29 amino acids, not 30. The half-life is approximately 30 minutes, which means it must be dosed multiple times daily to sustain growth hormone elevation. ConjuChem Biotechnologies never referred to this peptide as CJC-1295 in any clinical documentation. The 'no-DAC' nomenclature was a retroactive invention by suppliers attempting to differentiate inventory after the mislabelling became widespread. You can explore the structural precision we apply to every synthesis in our full peptide collection.

CJC-1295 With DAC vs. Modified GRF(1-29)

The DAC vs. no-DAC distinction is not a dosing preference. It's a structural difference that changes how the peptide behaves in vivo. CJC-1295 with DAC produces tonic, low-amplitude growth hormone elevation over days. Modified GRF(1-29) produces acute, high-amplitude pulses over minutes. These are not interchangeable tools. Research examining pulsatile vs. continuous GH secretion patterns requires one or the other, not both simultaneously.

CJC-1295 with DAC was evaluated in Phase I and Phase II clinical trials as a once-weekly subcutaneous injection for growth hormone deficiency. A 2006 study published in Clinical Endocrinology found that a single 60 mcg/kg dose elevated mean serum IGF-1 by 1.5–2× baseline for up to two weeks post-injection. The elevation was gradual. Not a spike, but a sustained increase that mimicked continuous low-dose GH infusion. Adverse events included injection site reactions and mild facial flushing; there were no reports of hypoglycaemia or oedema at clinically studied doses.

Modified GRF(1-29). Structurally identical to Sermorelin with the four DPP-IV-resistant substitutions. Was never intended to replace CJC-1295. It was developed as a short-acting GHRH analog for protocols requiring precise temporal control over GH pulses. Research combining modified GRF(1-29) with GHRP-6 or ipamorelin has shown synergistic amplification of growth hormone release when dosed simultaneously, but the effect dissipates within two hours. Our experience reviewing research logs shows that mislabelling these peptides as variants of the same compound has caused dosing errors, protocol mismatches, and wasted research funding across multiple institutions. The naming matters.

Storage and Reconstitution Requirements for CJC-1295

CJC-1295 ships as a lyophilised white powder in sterile glass vials, typically at 2 mg or 5 mg per vial. Store unreconstituted peptide at −20°C (standard freezer temperature) to prevent oxidation and aggregation. Once reconstituted with bacteriostatic water, the peptide must be refrigerated at 2–8°C and used within 28 days. This is the window during which the peptide retains ≥95% of its original potency based on HPLC assay data.

Reconstitution protocol: inject bacteriostatic water slowly down the inside wall of the vial. Never directly onto the lyophilised cake. The powder should dissolve without agitation within 30–60 seconds. Vigorous shaking denatures peptide bonds and creates aggregates that reduce bioavailability and may trigger immune responses. If the solution appears cloudy or contains visible particles, discard it. CJC-1295 with DAC should form a clear, colourless solution; any deviation signals degradation or contamination.

Temperature excursions above 25°C for more than 4 hours can denature the peptide structure irreversibly. This is particularly relevant during shipping: peptides shipped without cold packs during summer months may arrive degraded even if the vial appears intact. We've seen research institutions lose entire batches because storage protocols weren't followed post-delivery. Every peptide at Real Peptides is synthesised with exact amino-acid sequencing and shipped with cold chain integrity verification. But once it arrives, temperature discipline is the researcher's responsibility.

CJC-1295 Comparison: DAC vs. Modified GRF(1-29) vs. Native GHRH

Before selecting a peptide for growth hormone research, understand what each compound does differently at the receptor and clearance level.

| Peptide | Structure | Half-Life | GH Release Pattern | Albumin Binding | Primary Use Case | Professional Assessment |
|—|—|—|—|—|—|
| Native GHRH(1-44) | 44 amino acids, no modifications | <7 minutes | Acute pulse, rapid clearance | None | Diagnostic GH provocation tests | Too short-lived for sustained research applications. Baseline comparison only |
| CJC-1295 with DAC | 30 amino acids + DAC moiety | ~8 days | Sustained tonic elevation over days | Yes (via DAC) | Long-duration GH elevation studies | Authentic long-acting compound. Ideal for protocols requiring stable IGF-1 over weeks |
| Modified GRF(1-29) | 29 amino acids, no DAC | ~30 minutes | Acute pulse, moderate duration | None | Pulsatile GH release studies, combination protocols | Mislabelled as 'CJC-1295 no-DAC'. Structurally closer to Sermorelin than CJC-1295 |
| Sermorelin (GRF 1-29) | 29 amino acids, unmodified | ~10 minutes | Acute pulse, very rapid clearance | None | Clinical GH deficiency therapy (historical) | No DPP-IV resistance. Degrades faster than modified GRF(1-29) |

The 'Bottom Line' column exists because peptide selection isn't about preference. It's about matching pharmacokinetics to protocol design. If your study measures cumulative IGF-1 changes over 14–21 days, CJC-1295 with DAC is the only rational choice. If you're studying synergistic GH pulse amplification with GHRP analogs, modified GRF(1-29) is the tool. Native GHRH is a reference standard, not a research reagent.

What If: CJC-1295 Research Scenarios

What If I Receive a Vial Labelled 'CJC-1295 No-DAC'?

You've received modified GRF(1-29), not authentic CJC-1295. Verify the amino acid count and structure with the supplier's certificate of analysis. If the peptide is 29 amino acids and lacks the DAC moiety, expect a half-life of approximately 30 minutes. Not eight days. This changes dosing frequency, storage stability, and expected IGF-1 kinetics. Modified GRF(1-29) must be dosed 2–3 times daily to sustain GH elevation, whereas CJC-1295 with DAC is effective at once-weekly administration. If your protocol was designed for sustained IGF-1 elevation, the peptide you received won't match your experimental design.

What If the Reconstituted Peptide Looks Cloudy?

Discard it. Cloudiness indicates protein aggregation, bacterial contamination, or particulate matter. None of which are acceptable in research-grade peptides. Aggregated peptides have unpredictable bioavailability and may trigger immune responses that confound growth hormone assays. Reconstituted CJC-1295 should form a clear, colourless solution within 60 seconds of adding bacteriostatic water. If it doesn't, the peptide was either degraded before reconstitution or contaminated during mixing. Do not attempt to filter or salvage cloudy solutions.

What If I Left the Vial Out of the Fridge Overnight?

If the reconstituted peptide was left at room temperature (20–25°C) for fewer than 12 hours, refrigerate it immediately and use it within the next 48 hours. Beyond 12 hours at room temperature, assume potency has degraded by 10–15%. If the vial was left out for more than 24 hours or exposed to temperatures above 30°C, discard it. Temperature excursions denature peptide bonds irreversibly. The solution may still appear clear, but HPLC assay would show fragmented peptide chains and reduced receptor binding affinity. Unreconstituted lyophilised powder tolerates brief ambient exposure better than reconstituted solution, but both should return to cold storage within hours.

The Structural Truth About CJC-1295

Here's the honest answer: the peptide research community has been circulating incorrect nomenclature for over 15 years. Modified GRF(1-29) is not 'CJC-1295 no-DAC'. It's a completely different molecule with a different amino acid count, different pharmacokinetics, and different clinical history. ConjuChem Biotechnologies never used that term. The mislabelling originated with grey-market suppliers who didn't understand the distinction and labelled their inventory based on forum terminology rather than chemical structure. That mistake has now become the default naming convention across peptide catalogues, research logs, and even some published papers that should have known better.

The DAC moiety isn't optional. It's not a variant or an add-on. It's the defining structural feature that makes CJC-1295 clinically relevant. Without DAC, you have modified GRF(1-29). A peptide that works, but works completely differently. Calling them both CJC-1295 is like calling aspirin and ibuprofen 'the same pain reliever' because they both reduce inflammation. The mechanism overlaps, but the pharmacology does not.

If you're sourcing peptides for research and the supplier can't tell you the exact amino acid count, whether DAC is present, and what the expected half-life is. Find a different supplier. Precision matters. At Real Peptides, every synthesis is verified by HPLC and mass spectrometry before shipping. We don't guess at structure. We don't mislabel inventory. And we don't perpetuate naming conventions that originated from forum posts rather than chemical documentation.

Authentic CJC-1295 with DAC remains one of the most studied long-acting GHRH analogs in peptide research. Modified GRF(1-29) is a legitimate short-acting alternative. Both are useful. Neither should be confused with the other.

The peptide you choose determines the data you collect. Make sure you're using the right one.

References

Peer-reviewed sources on CJC-1295 indexed in PubMed, listed for research context. Real Peptides supplies CJC-1295 for laboratory research use only.

1. Netnography of Female Use of the Synthetic Growth Hormone CJC-1295: Pulses and Potions. Substance use & misuse, 2016. PMID 26771670. doi:10.3109/10826084.2015.1082595
2. Identification of CJC-1295, a growth-hormone-releasing peptide, in an unknown pharmaceutical preparation. Drug testing and analysis, 2010. PMID 21204297. doi:10.1002/dta.233
3. Activation of the GH/IGF-1 axis by CJC-1295, a long-acting GHRH analog, results in serum protein profile changes in normal adult subjects. Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society, 2009. PMID 19386527. doi:10.1016/j.ghir.2009.03.001
4. 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. The Journal of clinical endocrinology and metabolism, 2006. PMID 16352683. doi:10.1210/jc.2005-1536
5. 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. PMID 16822960. doi:10.1152/ajpendo.00201.2006
6. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. The Journal of clinical endocrinology and metabolism, 2006. PMID 17018654. doi:10.1210/jc.2006-1702
7. 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. doi:10.1210/en.2004-1286