CJC-1295 vs ipamorelin: which half of the GHRH stack has the deeper evidence file?

You want growth hormone to do more work without crossing into actual growth hormone. The forum recommendation lands almost immediately: CJC-1295 to raise the baseline, ipamorelin to add the pulse on top, run them together every night, problem solved. It’s one of the most-searched GHRH protocols on the internet because it sounds clean and it sounds finished.

It is not finished. CJC-1295 and ipamorelin are not two flavours of the same thing. They are two different peptides built decades apart in two different countries to push two different upstream levers on the pituitary. The stack is a marketing object. The evidence files for the two individual molecules look almost nothing alike, and the part of the protocol that has actually been tested in humans is only one of the two halves.

So before which one, or both, the honest move is the same as it ever is. Lay the two side-by-side and look at what each is carrying.

Two peptides, two upstream levers

These compounds come from different corners of the GH-axis story.

CJC-1295 is a modified version of human growth-hormone-releasing hormone — the natural 44-amino-acid pituitary signal, truncated to its first 29 residues and decorated with four substitutions to resist breakdown. The DAC variant adds a chemical handle that latches onto serum albumin and rides it for days. The 2005 Endocrinology paper by Jetté and colleagues at ConjuChem is the founding document — the lab built three maleimido bioconjugates of hGRF(1-29), tested each on rats, and identified CJC-1295 as the best of the three by a 4-fold increase in GH AUC and detectable plasma levels past 72 hours.

Ipamorelin is a different molecule entirely. A synthetic pentapeptide — five residues, non-natural amino acids, designed at Novo Nordisk in the 1990s. It is not a fragment of GHRH or of anything else in your body. Its target is the ghrelin receptor (GHSR-1a) — the same receptor older GH-releasing peptides like GHRP-2, GHRP-6, and hexarelin hit, but with a selectivity profile the older compounds did not have. Raun and colleagues in 1998 (European Journal of Endocrinology) introduced it as the first selective growth hormone secretagogue — strong dose-dependent GH release at potency comparable to GHRP-6 in rats, with cortisol, prolactin, and ACTH far less affected.

Different receptors. Different mechanisms. Different design eras. The reason the two get paired is that the pituitary has separate upstream channels for GHRH and ghrelin signalling, and the chemistry community worked out long ago that hitting both at once produces more GH than hitting either alone. That is the mechanistic foundation of the stack. It is also the part that has only been tested in animals.

The spec sheet

Pull the basic structural and regulatory facts into one frame, because the marketing flattens these into two recovery peptides when they are not.

Two things to take from the spec sheet. The half-life difference is huge — eight days versus two hours is the entire mechanical reason these get stacked in the first place. And the FDA picture is different from the PCAC peptides like BPC-157 or TB-500 — neither CJC-1295 nor ipamorelin is being evaluated at the July 2026 meeting, because both already had their PCAC reviews in late 2024 and the committee voted against inclusion on the 503A list. The regulatory question for these two is a different question entirely, and it has a different answer than the marketing pitch admits.

The DAC question on the CJC-1295 side

This is the part that breaks the comparison if you skip it.

The compound the Teichman 2006 trial characterised was CJC-1295 with DAC — the long-acting albumin-binding form, half-life roughly eight days. The compound widely sold to consumers as CJC-1295 is often CJC-1295 without DAC, sometimes labelled MOD-GRF(1-29) by more careful suppliers. Same four amino-acid substitutions for stability. No albumin handle. Half-life about half an hour.

These compounds share a name. They do not share a pharmacology. A buyer reading the Teichman 2006 data and assuming it applies to the form in the syringe is making an inference the chemistry does not support. The without-DAC form is dosed daily or multiple times a day — once an injection of the DAC variant is described as one shot a week, the conversation is no longer about the same compound.

The cleaner way to read the GHRH side of the stack is this: the well-characterised, sustained-elevation, weekly-dose evidence applies to CJC-1295 with DAC, and that is the variant we mean for the rest of this comparison. The without-DAC variant has its own short-half-life pharmacokinetics and its own daily-dosing protocol, and the published human file is not the same file.

Either way the molecule should be specified by the prescriber. Which version is this is not a marketing detail. It changes the dose, the frequency, the duration of effect, and what the protocol is supposed to do.

The human file, side-by-side

This is the part the stack pitch quietly skips, and it is where the two peptides actually separate.

Read those two columns honestly. On the CJC-1295 side, the human file is a clean Phase 1 PK/PD result and a same-year follow-up showing pulsatile GH is preserved. Both come out of 2006. Nothing past Phase 1 has been registered or published since. The science is confirmed at the hormone level and silent on everything downstream.

On the ipamorelin side, the file is shaped differently. A 1999 Phase 1 PK study established pharmacokinetics — short two-hour half-life, predictable GH release per dose. Then Helsinn took the compound into a real Phase 2 program for postoperative ileus. Beck and colleagues published the result in 2014 in the International Journal of Colorectal Disease — 117 patients, intravenous ipamorelin versus placebo, primary endpoint median time to first tolerated meal. Ipamorelin group 25.3 hours. Placebo group 32.6 hours. P-value 0.15. The trial did not reach statistical significance on its primary endpoint. The published conclusion is explicit: no significant differences between ipamorelin and placebo in the key and secondary efficacy analyses. Helsinn read the result the same way and discontinued the POI development program. The registered trial record NCT00672074 carries that history.

So the asymmetry is real, and it points in a direction the marketing does not. CJC-1295 has Phase 1 data and nothing further. Ipamorelin has Phase 1 data, plus a Phase 2 trial that ran cleanly, failed to meet its endpoint, and was the reason its sponsor walked away. The compound that is supposedly the clean half of the stack is the one with the null Phase 2 in print. The compound that has never been pushed into a real clinical trial is the one with the cleaner-looking record.

That is not because CJC-1295 is somehow more proven. It is because nobody has put it in a position to fail yet.

The stack-them pitch

The forum framing is usually that you do not need to choose. Run them together. CJC-1295 raises your GH and IGF-1 baseline. Ipamorelin pulses GH on top of that baseline. Together they produce sustained anabolic conditions, deeper sleep, better recomp, smoother recovery. The mechanism story is internally consistent.

The animal data has a foothold here. The 2026 Am J Sports Med primer by Mayfield and colleagues summarises the recent evidence: a CJC-1295 plus ipamorelin combination improved tetanic tension in glucocorticoid-induced muscle loss mouse models. In mice with steroid-induced muscle wasting, the stack moved a measured muscle endpoint. Suggestive.

The same review names, in the next breath, what is missing — no human orthopaedic data supports the combination. The 2026 Frontiers in Aging review by Mavrych and colleagues reaches the same conclusion across the whole growth-hormone-modulation cluster: mechanism is plausible, optimal dosing is not agreed, validated efficacy biomarkers do not exist, combination therapy effects are uncharacterised.

There is no published controlled human trial of the CJC-1295 plus ipamorelin stack for any indication. None. Not for body composition, not for sleep, not for recovery, not for healthspan. The mouse muscle finding is interesting, and it is the strongest published support the stack has — which is a way of saying the strongest support is a tetanic-tension reading in a steroid-wasted mouse limb.

So synergy in this protocol is a mechanistic prediction with one supportive rodent endpoint. It is not a clinical result. The forum framing of the stack as a settled choice is not what the literature says — the literature says nobody has run the trial that would settle it.

Where regulators stand

This is where the comparison to the PCAC-docket peptides actually matters.

Neither CJC-1295 nor ipamorelin is on the July 23–24, 2026 FDA Pharmacy Compounding Advisory Committee agenda per the April 2026 Federal Register notice. The notice names seven substances across the two-day session — BPC-157, KPV, TB-500, and MOTs-C on July 23, then Emideltide (DSIP), Semax, and Epitalon on July 24. CJC-1295 and ipamorelin are absent from both days.

That absence is doing more work than it might look. The PCAC review is the closest current US regulatory process for clarifying whether a peptide can be legally compounded by a US-licensed pharmacy under Section 503A. The peptides on the July docket are being evaluated, with FDA-reviewed indications attached, in a forum that produces a recommendation and downstream rulemaking. Whatever the committee decides for BPC-157 or TB-500, those compounds will be inside an active regulatory process by the end of July.

CJC-1295 and ipamorelin will not — because the agency already asked the question and got a no. Ipamorelin was evaluated at the October 29, 2024 PCAC meeting. CJC-1295 was evaluated at the December 4, 2024 meeting. PCAC voted against inclusion on the 503A list for both. The FDA’s stated reasoning followed the standard pattern: insufficient human safety data, mechanistic concerns about unintended endocrine effects, and lack of reproducible efficacy data outside small or open-label trials. Neither has an active NDA, an active development program, or a sponsor pushing them through any FDA pathway. ConjuChem ceased operations more than a decade ago. Helsinn walked after the Phase 2 result. The molecules live on in compounding because the chemistry is straightforward and demand is real — not because anyone is actively running them toward approval, and not because the regulatory question is unanswered. It was answered eight months before the July 2026 meeting, and the answer was no.

The practical version of that posture for a US patient: a doctor compounding CJC-1295 or ipamorelin today is doing it off-label, outside the Section 503A list, on the strength of mechanism plus pharmacology plus their own clinical judgement. There is no FDA-reviewed indication attached, because no review has occurred. The compounded product comes from a pharmacy operating under state board authority. The legal posture is materially different from a future state in which BPC-157 or TB-500 is on the 503A list with an FDA-reviewed indication and a controlled prescribing path.

WADA is the cleaner line and the same on both. Growth-hormone-releasing factors and ghrelin-receptor agonists both sit in the 2026 S2 prohibited list — peptide hormones, growth factors, related substances, and mimetics — prohibited at all times in and out of competition. The marketing’s not specifically named framing does not override the category language.

What would actually change the answer

If you wanted the comparison to land on something firmer than a clean Phase 1 versus a null Phase 2, here is the short list of evidence neither half of the stack currently has.

For CJC-1295, the missing piece is a controlled trial that goes past Phase 1 PK/PD. The 2006 trial measured GH and IGF-1. It did not measure body composition, sleep, cognition, or functional fitness. A trial in healthy adults running longer than the 2006 dosing windows, with the endpoints the marketing actually promises, would be the first time the right question has been asked of this compound.

For ipamorelin, the missing piece is a Phase 2 in a population the compound is actually being sold to. Beck 2014 tested surgical patients with ileus, not healthy adults on a longevity protocol. Whether the compound does anything useful for the off-label use case it is now prescribed for is a question Beck 2014 does not answer in either direction.

For the stack, the missing piece is a head-to-head controlled trial: CJC-1295 alone, ipamorelin alone, both together, placebo, with a body-composition or recovery endpoint. The mouse muscle finding in Mayfield 2026 is worth following up. Following it up means actually running the comparison in humans. That trial does not exist.

For long-term safety, neither compound has a published controlled exposure beyond weeks. People prescribed the stack for off-label longevity use often stay on it for months or years. That dataset is not in print for either molecule.

And, for both, independent replication of the foundational papers in modern protocols. Teichman 2006 has not been re-run with the variant currently sold to consumers. Beck 2014 has not been re-attempted in a different indication. The original groups have moved on. Nobody else has stepped in.

So which one, if you are stacking them anyway

The honest read sits somewhere uncomfortable for the protocol.

CJC-1295-with-DAC has a real Phase 1 PK/PD record and a mechanistic story that lines up with its chemistry. It has no Phase 2 in any indication, no human evidence for body-composition or longevity outcomes, no long-term safety dataset, and the version sold to consumers is sometimes a different compound (without DAC) than the one the published evidence covers.

Ipamorelin has a real Phase 1 PK record, a published Phase 2 trial that did not reach statistical significance on its primary endpoint, and a discontinued development program. Its selectivity profile in rats is genuinely the better-documented part of its file — but the part that has been tested clinically in humans is the postoperative-ileus indication, not the off-label longevity use case it is now sold for.

The stack itself has one tetanic-tension finding in a steroid-wasted mouse model and zero published human trials. The mechanistic case is coherent. The clinical case has not yet been made.

If somebody asked you to pick on evidence alone, the cleaner answer is neither of them is what the marketing claims. The deeper-evidence half of the stack is whichever one you read most carefully — because what you find on close inspection is roughly the same shape on both sides. The deeper evidence base the headline question presumes does not exist on either side. What exists is a Phase 1 PK study that worked, a Phase 2 efficacy trial that didn’t, and a wide gap between we tested it once and we know what it does.

When the legitimate version exists

Wolverine Health is building the version that does not ask you to take any of this on faith — physician-supervised peptide protocols, US-licensed compounding pharmacies, every batch third-party tested. The peptides on offer will be the ones the regulation actually allows, in the indications the FDA has actually reviewed, with a doctor who saw your labs writing the script. For CJC-1295 and ipamorelin specifically, that posture matters more than usual: PCAC has already voted against putting either compound on the Section 503A list, neither has an active FDA pathway, and the legitimate prescribing route for either today runs through off-label compounded use under state pharmacy authority — not the Section 503A list the July 2026 PCAC peptides are being evaluated against.

That landscape is the one we are designing the protocol around. The DAC-versus-no-DAC question gets answered on the label, not on the forum. The stack pairing gets evaluated on the evidence that exists for each half, not on the marketing that paired them. When the compounding service opens for these two molecules in particular — what variants, what frequencies, what clinical oversight, and which indications the supervising physician will actually prescribe for — we will say so plainly. Join the waitlist if you want a heads-up the moment that version is available.