CJC-1295 is a synthetic peptide hormone from the GHRH analog class - it mimics the body's own growth-hormone-releasing hormone, indirectly boosting growth hormone (GH) secretion from the pituitary gland. It belongs to the so-called GH secretagogues - substances that stimulate the body to release more of its own growth hormone. In peptide stacks, especially paired with ipamorelin, it is one of the most discussed compounds.

What is CJC-1295?

CJC-1295 was originally developed by ConjuChem Biotechnologies as a modified fragment of human GHRH (1-29) - so it is 29 amino acids long. The most important variant carries an additional Drug Affinity Complex (DAC), a chemical "anchor" that forms a strong chemical bond with serum albumin (the most abundant protein in blood plasma, which acts as the body's natural transport protein) after injection. That anchor is what dramatically extends its stay in the bloodstream.

A second variant without DAC (often called "modified GRF 1-29" or "CJC-1295 without DAC") has a half-life (i.e., the time until the body has cleared half of the substance) of only 30-60 minutes and is typically injected daily. The DAC version, in contrast, has a half-life of roughly 6-8 days.

How does CJC-1295 work?

The mechanism of action is well defined:

GHRH receptor binding: CJC-1295 binds the GHRH receptor on somatotroph cells in the anterior pituitary - the cells responsible for GH release.
cAMP signaling cascade: Binding triggers a kind of domino effect inside the cell (the so-called cAMP cascade) that ends in growth hormone release into the bloodstream.
IGF-1 rise: Released GH stimulates IGF-1 production in the liver. IGF-1 (Insulin-like Growth Factor 1) is the actual mediator of many GH effects - tissue repair, protein synthesis, fat metabolism.
Albumin anchor (DAC variant): The DAC modification forms a strong chemical bond between the peptide and circulating serum albumin, so it shares albumin's half-life of roughly 6-8 days.

Important: GHRH analogs like CJC-1295 mimic the physiological pulsatile GH release, in contrast to exogenous HGH, which produces constantly elevated GH levels. That pulsatility is precisely the argument for calling them "more physiological" and therefore safer.

That "pulsatile" claim only holds with caveats: it works for the non-DAC variant with its short half-life. The DAC version, with its extremely long residence time, produces a continuous GH signal rather than discrete pulses - in the community described as "GH bleed". Anyone invoking pulsatility as a safety argument has to strictly separate DAC from non-DAC.

What does the research show?

The evidence is clinical but thin:

Teichman et al. (2006, JCEM) showed in a Phase I study in healthy adults that a single CJC-1295 DAC dose raised GH release for at least 6 days and elevated IGF-1 in a dose-dependent manner for 9-11 days. With multiple doses, IGF-1 stayed above baseline for up to 28 days.
A follow-up (2009) documented changes in the serum protein profile after CJC-1295 injection.
The development program was halted after Phase II without Phase III data - CJC-1295 has no FDA or EMA approval.

Multiple dosing showed a cumulative effect: the peptide itself was still detectable in blood 10-13 days after single and multiple doses. This long residence time pharmacokinetically explains why trials only injected once or twice weekly - and is also an implicit warning about accumulation at higher off-label doses.

Why was CJC-1295 never approved?

The Phase II program in HIV-associated lipodystrophy was halted after the death of a trial participant - reported as a cardiovascular event (i.e., a heart or circulation problem) - and the developer ConjuChem subsequently went bankrupt, so CJC-1295 remains to this day merely an unapproved research-only peptide without FDA or EMA approval anywhere. The exact circumstances of the death were never fully published in peer-reviewed journals (i.e., specialist publications whose articles are checked by independent experts), so a direct causal link between the peptide and the event cannot be proven - but it was reason enough for the commercial program to fold. For every later safety discussion, this is the historical anchor: the only company that ever pushed it towards market threw in the towel.

How thin is the evidence base?

The human data on CJC-1295 essentially rests on a small group of healthy adults from the Teichman et al. Phase I program - the exact total number is not clearly reported in the publications - with no follow-up long-term or pivotal efficacy trials ever published, meaning any claim beyond short-term pharmacokinetics in healthy subjects rests on very thin evidence. When you read "clinically tested" in off-label contexts, that is essentially this one dose-escalation study (i.e., doses were gradually increased) plus a small follow-up - nothing more.

Post-2020, GHRH analog research also leans heavily on indirect evidence, notably from the approved drug tesamorelin. Anyone searching for CJC-1295 trials quickly hits tesamorelin data and misapplies it.

Does CJC-1295 help with fat loss?

Visceral fat reduction attributed to CJC-1295 has only been documented in animals and in adults with HIV-associated lipodystrophy (abnormal fat distribution) - in healthy adults there is no clinical efficacy trial, so the popular expectation of losing belly fat with CJC-1295 in otherwise healthy people has no real evidence base. The mechanism (higher GH or IGF-1) is plausible, but in a functioning endocrine system the extra stimulus does not appear to produce measurable fat loss. If you go looking for proof in bodybuilding forums, you mostly find animal studies or data from the HIV-lipodystrophy indication - neither is a valid basis for healthy users.

Dosing and practical use

Published studies used single subcutaneous doses of 30-250 micrograms per kilogram of body weight (i.e., injected under the skin; the multiple-dose arms used 60-250 µg/kg weekly), typically 1-2 times per week. Off-label protocols circulate at much higher "research" doses - there are no validated human data beyond the Phase I studies. If you're mixing CJC-1295 in practice, you'll want the injection calculator for proper dilution, a step-by-step mixing guide, and ideally a look at the CJC-1295/Ipamorelin profile for the typical stack context.

Safety and regulatory status

In Phase I, CJC-1295 DAC was considered safe and well tolerated. The most common side effect was transient local injection-site reactions (pain, swelling, redness). Concerns about abnormal bone and tissue growth (acromegaly risk), blood-sugar problems (glucose intolerance), or a suppressed pituitary gland (pituitary suppression) come from theoretical reasoning and long-term observations with real HGH - not from direct CJC-1295 trials.

Important for self-application: histamine reactions are well documented in the community - from harmless flushing and warmth at the injection site to generalized urticaria; in isolated documented cases an ambulance with an EpiPen was needed. Risk of severe reactions rises with accidental intravenous injection and with progressive sensitization over multiple weeks. A clear stop rule: if redness and welts get worse with each injection, stop - continuing to inject can worsen the reaction instead of "getting used to it".

The label of the approved GHRH analog tesamorelin and the broader GHRH analog class also list flu-like symptoms, headache, irritability, anxiety, and nausea - there is no FDA listing for CJC-1295 itself, since the compound was never approved.

Without approval and outside clinical studies, CJC-1295 DAC is a typical gray-market compound - sourcing, purity, and the lab certificate of analysis (CoA) are the biggest practical risks. How to vet vendors is laid out in Peptigraph's Vendor Radar.

Evidence at a glance

Research status

CJC-1295 is a synthetic, long-acting growth hormone-releasing hormone (GHRH) analog that is not approved by the FDA or EMA for any indication. No NDA or BLA has been submitted, and there is no marketing authorization from the EMA [8, 11, 16, 17]. In the US, it is available only through 503A and 503B compounding pharmacies [11, 16]. Human evidence is limited to short-term Phase I trials [6, 19] and an unknown-status Phase II trial [5, 13]. Preclinical evidence is derived from rat [4] and mouse models [2, 22]. The FDA has flagged CJC-1295 for serious adverse events and states that available clinical data are limited [7]. In 2025, the FDA classified a recall of a CJC-1295 injectable product as Class II due to a lack of assurance of sterility [20].

Human evidence

Phase I Trials: Two randomized, placebo-controlled, double-blind, ascending dose trials were conducted in healthy adults (ages 21-61) with durations of 28 and 49 days [6, 19]. Subcutaneous administration resulted in sustained, dose-dependent increases in mean plasma GH concentrations by 2- to 10-fold for 6 days or more, and IGF-I concentrations by 1.5- to 3-fold for 9-11 days [1, 6]. Pulsatile secretion of GH persists during continuous stimulation by CJC-1295 [3, 15]. The estimated half-life in humans is reported as 5.8-8.1 days [1], 6-8 days [6], and 8-10 days [9]. A cumulative effect was observed after multiple doses, with IGF-I levels remaining above baseline for up to 28 days [1, 6]. A 2009 study showed that activation of the GH/IGF-1 axis results in serum protein profile changes in normal adult subjects [9, 10]. Phase II Trials: A multicenter, randomized, placebo-controlled, double-blind Phase 2 study was registered to evaluate efficacy and safety for 12 weeks in HIV-infected patients with HIV-associated visceral obesity (NCT00267527 / 2005-003797-25) [5, 13]. The current status of this trial on ClinicalTrials.gov is listed as "Unknown" [5].

Dosages in studies & practice

The following dosages appear in the cited sources and are reported strictly as historical clinical trial parameters, not as recommendations or instructions: 30 or 60 µg/kg (subcutaneous) was reported in a Phase 1 trial as safe and relatively well-tolerated [1, 6]. 60 or 90 mcg/kg (subcutaneous, single dose) was administered to healthy adult men in a separate study [15]. Once-daily administration was used in the GHRH knockout mouse study (animal model) [2, 22].

Risks & side effects

The most frequently reported adverse events in Phase I trials were injection site reactions, consisting of transient pain, swelling, and induration, sometimes accompanied by local urticaria [1, 6]. An increase in heart rate that was dose-dependent was also reported [14, 15]. No serious adverse reactions were reported in these early Phase 1 trials [1, 6, 14, 15]. However, the FDA has identified serious adverse events associated with CJC-1295, including increased heart rate and systemic vasodilatory reaction [7]. The FDA also notes that compounded drugs containing CJC-1295 may pose risks for immunogenicity for certain routes of administration and may have complexities regarding peptide-related impurities and API characterization [7]. Additionally, a recall of a CJC-1295 injectable product was classified as Class II due to a lack of assurance of sterility [20].

Research gaps

The evidence base for CJC-1295 in humans is thin, consisting of short-term, small studies, some of which were conducted by groups with ties to the peptide's original developer (ConjuChem Biotechnologies) [8]. The FDA explicitly states that available clinical data are limited [7]. There is a contradiction in safety reporting: while early Phase 1 trials reported no serious adverse reactions [1, 6, 14, 15], the FDA has subsequently identified serious adverse events [7]. Preclinical animal models are generally poor predictors of human toxicities in early clinical trials [21], limiting the extrapolation of animal data for human harm-reduction purposes. Claims of benefits such as fat loss or anti-aging are primarily supported by animal studies rather than robust human clinical data [12]. The human evidence demonstrates biochemical effects (increased GH and IGF-1) but does not establish clinical outcomes such as muscle gain, fat loss, or cognitive benefits.

Editorial, sourced from primary literature - not medical advice.

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