Contents
Key findings
- 1CJC-1295 with DAC reliably raises growth hormone 2–10× and IGF-1 1.5–3× for a week or more after a dose, in a small randomised placebo-controlled study of healthy adults.
- 2Ipamorelin releases GH via the ghrelin receptor with less cortisol/prolactin than older secretagogues — an animal-pharmacology property. Its only outcome trial (post-operative ileus) was negative and development stopped.
- 3No controlled human trial has measured body composition, strength, recovery, sleep quality or any aging endpoint for either peptide or the combination.
- 4Growth hormone itself, given to healthy older adults in trials, produces small body-composition changes and frequent side effects — fluid retention, joint pain, glucose intolerance — a cautionary benchmark for "restoring GH".
- 5FDA placed both in category 2 of its compounding interim policies in September 2023 over immunogenicity concerns; ipamorelin acetate is still listed there under the 503B policy, while the CJC-1295 nomination was withdrawn. Neither is eligible for compounding. Both are banned in sport.
Evidence level
Small randomised human pharmacology studies show CJC-1295 (DAC) raises GH and IGF-1 for days; ipamorelin releases GH in phase 1 studies. There are no controlled trials of body composition, strength, recovery, sleep or aging outcomes for either, alone or combined.
Regulatory status
Neither is FDA-approved; both development programmes were discontinued. Both were placed in category 2 of the FDA compounding interim policies in September 2023; on the list current 22 April 2026 CJC-1295 appears among withdrawn nominations, while ipamorelin acetate remains in category 2 under the 503B policy. Both are prohibited in sport under WADA S2.
CJC-1295 and ipamorelin are almost always sold together, as a "stack" that promises lean muscle, fat loss, deeper sleep and slower aging by "restoring youthful growth hormone." Every part of that sentence except the hormone bit is untested. This analysis lays out what has been measured, what hasn't, and why the untested risks deserve more attention than they get.
The question readers ask
Does the CJC-1295/ipamorelin combination change body composition, recovery or aging? No trial has measured any of those outcomes. What has been measured — carefully, in randomised studies — is that these compounds raise growth hormone and IGF-1. Everything else is inference.
The two compounds
CJC-1295 is a modified 29-amino-acid fragment of growth hormone-releasing hormone (GHRH). The "DAC" version carries a chemical group that binds albumin in the blood, so a single dose stimulates GH release for a week or more; the "no-DAC" version (Mod GRF 1-29) acts for minutes. It was developed by ConjuChem in the early 2000s and abandoned around 2006 before any outcome trial.
Ipamorelin is a five-amino-acid peptide that stimulates GH release through the ghrelin receptor. It was designed by Novo Nordisk in the 1990s to be more selective than earlier "GHRPs" — releasing GH without much cortisol or prolactin, a property shown in animal models[3]. It was later studied by another company for post-operative ileus; the phase 2 trial did not show efficacy and development stopped[4].
They are combined because GHRH analogues and ghrelin-receptor agonists act through different receptors and produce larger GH pulses together in pharmacology studies. That is a real, well-described synergy — on a hormone level.
What the human research shows
The best study of CJC-1295 is a genuine randomised, placebo-controlled trial in 53 healthy adults[1]. Single doses raised mean GH concentrations 2- to 10-fold for at least six days and IGF-1 1.5- to 3-fold for nine to eleven days; repeated doses sustained the elevation. A companion study in 11 men showed the natural pulsatile pattern of GH secretion was preserved, with bigger pulses[2].
Study details: 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
- Study type
- Randomised, placebo-controlled, phase 1
- Population
- Healthy adults 21–61
- Sample size
- 53
- Primary result
- GH increased 2–10× for ≥6 days; IGF-1 1.5–3× for 9–11 days after single doses.
- Limitations
- Short; hormone endpoints only.
- Year
- 2006
- Source
- Journal of Clinical Endocrinology & Metabolism(link not yet independently re-verified)
For ipamorelin, human data are phase 1 pharmacology (GH release, tolerability) and the negative ileus trial. We could not find a published controlled human trial of ipamorelin for any of the uses it is marketed for.
That is the complete controlled human literature. Nothing on muscle mass. Nothing on fat. Nothing on strength, recovery, injury, sleep architecture, skin, cognition or any aging endpoint. Nothing on the combination.
The benchmark nobody mentions: growth hormone itself
If secretagogues work by raising GH, the obvious question is what raising GH does in healthy adults. That has been tested. A systematic review of 31 studies of GH given to healthy older adults found small changes — a couple of kilograms less fat, a couple more lean mass — with no improvement in strength or function, and significantly more soft-tissue swelling, joint pain, carpal tunnel syndrome and glucose intolerance[5]. Secretagogues might behave better because they preserve pulsatility and are self-limited by feedback. Or they might not. No one has checked.
Study details: Systematic review: the safety and efficacy of growth hormone in the healthy elderly
- Study type
- systematic-review
- Population
- Healthy elderly adults in 31 studies
- Sample size
- 220
- Primary result
- GH modestly reduced fat mass and increased lean mass without improving strength or function; significantly increased soft-tissue oedema, arthralgia, carpal tunnel and glucose intolerance.
- Year
- 2007
- Source
- Annals of Internal Medicine(link not yet independently re-verified)
The unanswered risks
Because outcome trials were never run, neither were long-term safety studies. The concerns are not speculative in kind, only in degree:
- Glucose and insulin. GH is counter-regulatory to insulin; sustained elevation impairs glucose tolerance in the GH trials above.
- Fluid retention and joint pain. The commonest GH side effects; short CJC-1295 studies noted flushing, headache and injection-site reactions.
- IGF-1 and cancer. Higher IGF-1 is associated with some cancers in observational data, and reduced GH/IGF-1 signalling is linked to longer lifespan in several animal models — the opposite of the "restore GH for longevity" pitch (see the healthy-aging hub).
- A death in development. A participant died during the ConjuChem CJC-1295 programme; it was reported as unrelated to the drug, but the programme was halted and never resumed.
- Product quality. Both are sold only as unregulated products; content and purity are unverified.
Regulatory position
Neither compound is approved anywhere. On 29 September 2023 the FDA placed both in category 2 of its compounding interim policies — substances the agency judges may present significant safety risks — citing possible immunogenicity for certain routes of administration. Their positions have since diverged: on the list current at 22 April 2026, ipamorelin acetate remains in category 2 under the 503B policy, while CJC-1295 appears among substances whose nominations were withdrawn by the nominators[6]. A withdrawn nomination is an administrative change, not a safety finding, and neither compound is on the 503A bulks list, so neither can lawfully be compounded. Both are prohibited in sport under WADA's S2 class (peptide hormones, growth factors and related substances).
Grades by claim
| Claim | Best evidence | Grade |
|---|---|---|
| CJC-1295 raises GH and IGF-1 | Randomised placebo-controlled study, n=53 | Preliminary evidenceSmall human RCT, hormone endpoint |
| Ipamorelin releases GH | Phase 1 pharmacology; animal selectivity data | Preliminary evidenceEarly human |
| Builds muscle / reduces fat | None | Preclinical evidenceNo outcome trial |
| Improves recovery or sleep | None | Preclinical evidenceNo outcome trial |
| Slows aging | None; contrary animal signals | Unsupported evidenceContradicts available biology |
| Safe long-term | None | Unsupported evidenceNo data |
Where to go next
- CJC-1295 profile and ipamorelin profile.
- CJC-1295 vs ipamorelin vs tesamorelin — the one GHRH analogue that did complete phase 3.
- Body composition hub — where the strong evidence actually is.
Frequently asked questions
- Does CJC-1295/ipamorelin build muscle?
- No controlled trial has measured it. The studies show hormone levels rise; they do not show more muscle, less fat, or better recovery.
- Why combine CJC-1295 with ipamorelin?
- GHRH analogues and ghrelin-receptor agonists act on different receptors and release more GH together in pharmacology studies. That is a hormone effect, not an outcome, and the combination has never been tested for any clinical endpoint.
- Is CJC-1295 safer than growth hormone injections?
- Unknown. It preserves natural GH pulsatility, which is theoretically favourable, but there are no long-term human safety data. The risks of GH itself in healthy older adults — fluid retention, joint pain, glucose intolerance — are a reasonable starting assumption until shown otherwise.
References
Numbered in order of first use. Study type is shown for every source; see our methodology for how we rank evidence.
- 1.
Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA. 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 Journal of Clinical Endocrinology & Metabolism, 2006.
Randomized controlled trialHealthy adults 21–61n = 53
Result: GH increased 2–10× for ≥6 days; IGF-1 1.5–3× for 9–11 days after single doses.
Limitations: Short; hormone endpoints only.
↑ back to text - 2.
Ionescu M, Frohman LA. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog Journal of Clinical Endocrinology & Metabolism, 2006.
Human studyHealthy menn = 11
Result: GH pulsatility preserved with amplified pulses.
↑ back to text - 3.
Raun K, Hansen BS, Johansen NL, et al.. Ipamorelin, the first selective growth hormone secretagogue European Journal of Endocrinology, 1998.
Preclinical
Result: Selective GH release without significant ACTH/cortisol in animal models.
↑ back to text - 4.
Clinical trials of ipamorelin (search) ClinicalTrials.gov.
Trial registry
Result: Phase 1/2 studies including post-operative ileus; none for body composition or aging.
↑ back to text - 5.
Liu H, Bravata DM, Olkin I, et al.. Systematic review: the safety and efficacy of growth hormone in the healthy elderly Annals of Internal Medicine, 2007.
Systematic reviewHealthy elderly adults in 31 studiesn = 220
Result: GH modestly reduced fat mass and increased lean mass without improving strength or function; significantly increased soft-tissue oedema, arthralgia, carpal tunnel and glucose intolerance.
↑ back to text - 6.
Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks (category 2 list) U.S. Food and Drug Administration, 2026.
Regulatory source
Result: CJC-1295 appears on the withdrawn-nomination list; ipamorelin acetate remains in category 2 under the 503B interim policy (added 29 September 2023).
↑ back to text
Review status: Editorially reviewed against primary sources. This article was fact-checked against the primary sources listed in the references by our editorial team, and it has not been reviewed by a licensed clinician. It is educational content, not medical advice. Read our editorial policy and methodology. Spotted an error? Tell us.
