CJC-1295

At a glance

What is CJC-1295?

CJC-1295 is a synthetic peptide designed to mimic your body's natural growth hormone-releasing hormone (GHRH) — the signal that tells your pituitary gland to produce and release growth hormone. What makes CJC-1295 different from natural GHRH is that it lasts dramatically longer in the body: days instead of minutes.^[1]

The compound was developed by ConjuChem Biotechnologies, a Montreal-based biotech company, and first described scientifically in 2005. ConjuChem's innovation was a proprietary "Drug Affinity Complex" (DAC) — a chemical modification at the end of the peptide that allows it to bind to albumin (a protein in your blood), extending its half-life from minutes to approximately 6-8 days.

The critical distinction: with DAC vs. without DAC

When people discuss "CJC-1295," they may be talking about two related but pharmacologically distinct compounds:

• CJC-1295 with DAC is the original compound tested in clinical trials. The DAC allows it to bind to albumin, producing sustained, continuous GH elevation over days. Half-life: 6-8 days.
• CJC-1295 without DAC (also called Mod GRF 1-29 or Modified GRF 1-29) is the same peptide backbone without the albumin-binding modification. It has a much shorter half-life (~30 minutes) and produces pulsatile rather than continuous GH release.

This distinction matters because most community protocols use the version without DAC, reasoning that pulsatile GH release better mimics the body's natural pattern. But the published clinical trial data is exclusively on the version with DAC. They are not interchangeable, and evidence for one does not automatically apply to the other.

How it works

In simple terms, CJC-1295 tells your pituitary gland to make and release more growth hormone. It does this by binding to the same receptor as your body's natural GHRH signal — but because of its chemical modifications, it stays active for much longer than the natural hormone.^[2]

The result is a sustained elevation of both growth hormone (GH) and IGF-1 (insulin-like growth factor 1, which GH stimulates your liver to produce). Importantly, Phase I data showed that GH secretion under CJC-1295 remains pulsatile — it comes in bursts rather than a steady stream — which preserves the body's natural rhythm.^[3]

What the research says

CJC-1295 works. Phase I data clearly shows it elevates growth hormone and IGF-1 in a sustained, dose-dependent manner. But working as a pharmacologic tool and working as a medicine are two very different things — and the Phase II trial that might have bridged that gap was halted after a participant died.

Research timeline

CJC-1295 has a relatively brief research history — most of it concentrated in a single year — followed by complete abandonment of clinical development:

Human clinical trials

The published human evidence for CJC-1295 consists of two Phase I studies from the same research program and one halted Phase II trial. Here's what each found:

Both Phase I studies were published in the Journal of Clinical Endocrinology & Metabolism (JCEM) in 2006 — the single-dose study by Teichman et al. and the multiple-dose study by Ionescu and Frohman.^[2][3] The Phase II trial was registered as NCT00267527 but predated mandatory results reporting, and no data was ever published.^[7]

Animal studies

The preclinical evidence base for CJC-1295 is narrower than some peptides but mechanistically sound. The most important study demonstrated that once-daily CJC-1295 normalized body weight and length in GHRH knockout mice — animals genetically engineered to lack GHRH signaling — confirming that CJC-1295 functionally activates the GHRH receptor in vivo.^[4]

CJC-1295's mechanism doesn't require extensive preclinical validation in the same way as a novel target would, because the GHRH-GH-IGF-1 axis is one of the most thoroughly studied hormonal pathways in endocrinology. The question was never whether a GHRH analog would elevate GH — it was whether the DAC technology could extend the duration of action. The Phase I data answered that question.

What the evidence shows

CJC-1295 is marketed for a range of benefits — from body recomposition to better sleep to anti-aging. Here's what the published research actually supports:

Safety & side effects

The Phase II death

The most significant safety event in CJC-1295's history is a death during the Phase II clinical trial. A participant in a multi-site study of CJC-1295 for HIV-associated lipodystrophy died from myocardial infarction approximately 3 hours after receiving the 11th weekly dose. The attending physician attributed the death to underlying asymptomatic coronary artery disease with plaque rupture — essentially, a heart attack that could have happened at any time.^[8]

However, it's important to note that the Phase I studies observed vasodilatory effects (flushing) and transient heart rate changes in participants. Whether CJC-1295 could have contributed to the cardiovascular event — perhaps by triggering hemodynamic stress in a patient with vulnerable plaque — is unknown. ConjuChem made the decision to permanently halt all development.

What the FDA has said

Those same cardiovascular signals are the reason CJC-1295 was restricted for compounding, and the FDA has now published its reasoning. In the safety rationale accompanying its bulk-substance categories — page content current as of April 22, 2026 — the agency writes:^[9]

FDA has identified serious adverse events associated with CJC-1295 including increased heart rate and systemic vasodilatory reaction. Available clinical data are limited.

Reporting in April 2026 established that this and the other 2023 peptide category decisions rested on documented immunogenicity risk and adverse events in study subjects across six compounds — GHRP-2, ibutamoren, ipamorelin, CJC-1295, AOD-9604 and melanotan II — including deaths, with causality not established.^[12]

Read plainly: the two independent lines of evidence about CJC-1295's cardiovascular effects — the Phase I flushing and heart rate changes, and the fatal myocardial infarction that ended the Phase II — are the same signals FDA cites. That does not prove CJC-1295 causes cardiac harm. It does mean the concern is not a regulatory abstraction, and "available clinical data are limited" is the operative phrase twenty years on.

A 2026 review in Sports Medicine covering CJC-1295 and the other GH-axis peptides comes to the same place: favorable animal data, scarce rigorous human safety data, real potential for serious harm.^[13]

What Phase I showed

In the Phase I studies at doses of 30-60 mcg/kg, CJC-1295 was generally well-tolerated. Observed side effects included:^[2]

• Injection site reactions (redness, pain)
• Transient flushing
• Headache
• Dizziness
• No serious adverse events at the studied doses

Community-reported side effects

Among people who have used CJC-1295 (primarily the no-DAC version) outside of clinical settings, commonly reported effects include:

• Water retention and bloating
• Tingling or numbness in hands and fingers (carpal tunnel-like symptoms, consistent with elevated GH)
• Increased hunger (especially when combined with ipamorelin)
• Vivid dreams and disrupted sleep (especially the DAC version)
• Flushing after injection
• Fatigue and joint pain
• Lightheadedness (more common at higher doses)

These are self-reported and not from controlled studies.

Theoretical risks

How people use it

CJC-1295 is most commonly discussed in the context of body composition optimization, anti-aging, and recovery. Here's what the landscape of use looks like — with important caveats.

The CJC-1295 / Ipamorelin stack

The most common community protocol pairs CJC-1295 (usually the no-DAC version) with ipamorelin, a ghrelin receptor agonist. The rationale: CJC-1295 stimulates GH release via the GHRH receptor, while ipamorelin stimulates it via the ghrelin receptor. These two pathways are synergistic — together, they amplify GH release beyond what either achieves alone.

Before the FDA's Category 2 classification in 2023, the CJC-1295/ipamorelin combination was one of the most commonly prescribed peptide protocols through telehealth and anti-aging clinics. It was often positioned as a "safer alternative to HGH."

Administration

• Subcutaneous injection is the standard route for both versions
• CJC-1295 with DAC: Typically discussed as weekly dosing (long half-life)
• CJC-1295 without DAC (Mod GRF 1-29): Typically discussed as 1-3 times daily (short half-life), often before bed to coincide with the natural nocturnal GH pulse

If you plan to reconstitute peptides, see our reconstitution guide for safety-first preparation instructions.

Legal & regulatory status

As of August 2026:

FDA status

CJC-1295 is not FDA-approved for any indication. Its regulatory history is unusually convoluted:

• 2023: FDA places CJC-1295 on the Category 2 list of bulk drug substances that may present significant safety risks in compounding.
• September 2024: The nominator withdraws. CJC-1295 moves into FDA's separate "nominated but withdrawn" table rather than the active Category 2 table.
• 2024: The Pharmacy Compounding Advisory Committee (PCAC) reviews CJC-1295 and recommends against including it in the 503A bulks list, which would permit compounding.
• April 22, 2026: The most recent update to FDA's category page. CJC-1295's position is unchanged, and FDA's stated safety rationale — increased heart rate, systemic vasodilatory reaction, limited clinical data — remains published alongside it.^[9][10]

WADA / USADA status

CJC-1295 is prohibited at all times under WADA Section S2, specifically S2.2.4 (growth hormone releasing factors), where the 2026 List names it explicitly alongside CJC-1293, sermorelin and tesamorelin. Testing methods for detecting CJC-1295 in biological samples have been published.^[6][11]

All S2 substances are non-Specified. Sanctions run up to four years, but the actual outcome depends on whether the athlete can establish how the substance entered their system and whether the violation was intentional — four years is the ceiling, not an automatic result.

International status

CJC-1295 is not approved for clinical use in any country. ConjuChem Biotechnologies, the original developer, is defunct. No pharmaceutical company is currently pursuing clinical development of CJC-1295. The compound is available as a research chemical from online suppliers.

Developer status

ConjuChem Biotechnologies, which held the patents on the DAC technology and CJC-1295 formulation, no longer exists. Many patents have expired or been abandoned. There is no active pharmaceutical development program for CJC-1295 anywhere in the world.

How CJC-1295 compares

To put CJC-1295 in context, here's how it compares to sermorelin — the FDA-approved GHRH analog that is essentially CJC-1295's predecessor:

The comparison is instructive. Sermorelin is the native GHRH (1-29) fragment — essentially the unmodified version of what CJC-1295 was built from. Sermorelin earned FDA approval for pediatric growth hormone deficiency and was only discontinued due to supply chain issues, not safety concerns. CJC-1295 was designed to be a better sermorelin — longer-lasting, less frequent dosing — but its development was cut short before those advantages could be proven in clinical outcomes.