CJC-1295

CNot approvedCJC-1295 DACmodified GRF(1-29)tesamorelin's cousin
In one paragraphCJC-1295 is a modified growth-hormone-releasing hormone fragment engineered to bind albumin so that it lasts days rather than minutes. Early human trials showed substantial, sustained rises in growth hormone and IGF-1 with weekly dosing. Development was discontinued and no trial has measured whether that translates into any clinical outcome. It is not approved anywhere and is banned in sport.
Schematic 3D structure of CJC-1295
29 residues · modified GRF(1-29), helical · schematic
Overall gradeC Weak
Human trialsEarly-phase only; programme discontinued
Outcomes graded4
Last reviewed2 September 2026
EvidenceWhat it isHow it worksUnknownsRegulationQuestionsReferences

What the human research shows

A drug that did exactly what it was designed to do to a blood marker, and was never tested for whether that mattered. The hormone data are real and from proper early-phase trials. Everything downstream of the hormone is unmeasured.

OutcomeGradeEffect sizeHuman studiesWhere the evidence comes from
Growth hormone / IGF-1 elevationBProbableLargePhase 1 / early phase 2Weekly dosing produced sustained multi-fold GH increases and IGF-1 elevations over weeks in healthy adults — a large, reproducible effect on the marker.1
Body compositionDNo human evidenceNot measurableNoneNo trial has measured muscle or fat change.
Any clinical outcomeDNo human evidenceNot measurableNoneThe programme was discontinued before efficacy trials in any indication.
Safety in humansadverseCWeakNot measurableEarly-phase onlyShort early-phase exposure only. Long-term safety of sustained IGF-1 elevation is unstudied.
AMultiple good human trials, consistentBSome human trials, mostly consistentCFew or weak human studiesDAnimal or anecdotal onlyeffect size · red = adverse

Literature searched to 2 September 2026. Human studies only; animal and cell work informs the mechanism section and nothing else.

What it is

CJC-1295 is the same 29-amino-acid GHRH fragment as sermorelin, with four amino-acid substitutions to resist breakdown and — in the DAC version — a chemical linker that binds it to albumin in the blood. Albumin circulates for weeks, so the peptide goes with it. That is the whole design idea: turn a minutes-long hormone into a weekly injection.

Confusingly, much of what is sold as "CJC-1295" without DAC is simply modified GRF(1-29), which does not have the long half-life. The two are routinely conflated in marketing.

How it is thought to work

Same receptor as sermorelin and tesamorelin, sustained far longer. The pharmacological question that was never answered is whether continuous elevation is better or worse than the body's natural pulses — growth hormone is normally released in bursts, and receptors respond differently to a constant signal.

What is still unknown

  • Whether sustained rather than pulsatile GH elevation is beneficial or harmful.
  • Any clinical outcome at all.
  • Long-term safety; the trials never ran long enough to say.

Regulatory status

European Union
Unapproved medicinal product

No authorisation; sale for human use is an offence for the seller.

United States
Not approved

Never approved; development discontinued.

Sport (WADA)
Prohibited

GH-releasing factors banned at all times.

Australia
Prescription-only or unapproved

Scheduled by the TGA; not available without a prescription.

Questions people actually ask

Does CJC-1295 build muscle?
Unknown. It raises growth hormone and IGF-1 substantially — that part is well documented in early trials. Whether that changes muscle or fat has never been measured in a trial.
What is the difference between CJC-1295 with and without DAC?
The DAC (drug affinity complex) version binds to albumin and lasts about a week. Without DAC it is essentially modified GRF(1-29), lasting around half an hour. They are sold under the same name.
Why was development stopped?
The programme was discontinued after early-phase work, without efficacy trials in any indication.

References

  1. 1

Change log

  • 2026-09-02Initial publication. Hormone effect graded B; all downstream outcomes D.