Preloaded Autoinjector | CJC-1295 (No DAC) + Ipamorelin | 3ml Pen | 15mg

The cjc 1295 ipamorelin pen is a preloaded 3ml research autoinjector holding two peptides in one solution at 5.0 mg/ml combined, giving 15mg in total. Both substitutions that separate this GRF analogue from sermorelin, Gln8 and Leu27, were made to remove solution degradation sites, which is why a blend of a 29-mer and a pentapeptide can be offered as a liquid at all.

Specification Table

What Changes When a Two-Peptide Blend Ships in Solution?

Two molecules with different failure modes now share one buffer, one pH and one shelf life, and the compromise that suits the 29-mer is not automatically the one that suits the pentapeptide.

Take the GRF analogue first, because its substitutions are a formulation argument in disguise. Friedman and colleagues (1991) showed that degradation of growth hormone releasing factor analogues in neutral aqueous solution is driven by deamidation of asparagine residues. Native GRF(1-29) carries Asn8; this analogue carries Gln8, and glutamine deamidates far more slowly. Native GRF carries Met27, the residue most readily oxidised in any peptide that has one; this analogue carries Leu27. D-Ala2 blocks dipeptidyl peptidase IV, and Ala15 raises helix propensity. Two of the four substitutions answer solution chemistry directly.

That does not make the molecule inert in water. Asp3-Ala4 remains, and the succinimide route converts it to isoaspartate, which is isobaric with the parent and invisible to a mass check; Oliyai and Borchardt (1993) put isomerisation as the dominant path between pH 4 and 6. Asp25-Ile26 is sterically protected by the branched isoleucine, and Tyr1 and Tyr10 photo-oxidise slowly. The larger physical problem is that Ala15 was chosen to stabilise a helix: a helical, amphipathic, roughly plus four charged 29-mer is more prone to surface adsorption and self-association than any tetrapeptide, and FDA reviewers in December 2024 described the CJC-1295 substances as sensitive to formulation and environmental conditions with a risk of aggregation. No aggregation study of this peptide exists.

Ipamorelin is the quieter of the two on paper. It has no asparagine, aspartate, glutamine, methionine, cysteine or tryptophan, so deamidation, isomerisation and thioether oxidation have nothing to act on, and the N-terminal alpha-aminoisobutyric acid is too hindered for easy diketopiperazine formation. What remains is His2, oxidisable at plus 16 daltons, and D-2-naphthylalanine, whose ring absorbs out to about 320 nanometres and is the reason light protection has any mechanism here. With D-phenylalanine beside it, that ring also makes the molecule hydrophobic, at a calculated XLogP3 of plus 1.8.

Solubility is where the two components part company. FDA quotes ipamorelin free base at 0.0032 mg/ml in water against 5 mg/ml for the acetate salt, a factor of about 1,560, so a device holding 5 mg/ml combined can only work with the salt form and at a pH that keeps the histidine protonated. Both peptides are cationic, so charge-pair precipitation between them is not expected, but both adsorb to glass silanols and to hydrophobic polymer, and tesamorelin’s approved formulation includes polysorbate 20 for exactly that reason. Whether this vehicle contains a surfactant is not stated.

The only figure on record for solution behaviour is a supplier statement quoted in FDA’s review: 2 to 3 weeks stored at 4 degrees Celsius for ipamorelin, against 4 years at minus 20 degrees for the acetate as a solid. Those are certificate statements rather than studies, and no work of any kind addresses cjc 1295 ipamorelin solution stability for the two peptides together in one buffer.

Why Both Approved GRF Analogues Were Lyophilised

Two growth hormone releasing factor analogues have US approval, and both were sold as dry powder requiring reconstitution, which is the most useful piece of formulation evidence available for this class.

Sermorelin acetate was approved as Geref under NDA 020443 in 1997 and later discontinued for commercial rather than safety reasons. Tesamorelin is approved as Egrifta SV, supplied as 2 mg of lyophilized powder with histidine, mannitol, polysorbate 20 and sucrose, reconstituted with sterile water, stored at 20 to 25 degrees Celsius protected from light, injected immediately and with the remainder discarded. Neither product is the peptide in this device, and this research preparation is not either of them.

The instruction to inject immediately and discard the remainder is the part worth reading twice. A manufacturer holding full stability data on a related GRF analogue chose not to let the reconstituted solution stand at all, which puts the burden of proof for a liquid presentation in this class on the certificate rather than on precedent.

How Concentrated Is the CJC 1295 Ipamorelin Pen?

Fifteen milligrams in 3 ml is 5.0 mg/ml combined, each 0.01 ml increment carries 50 micrograms of total peptide and each 0.1 ml carries 500 micrograms, and the per-component figures depend on a split the product record does not state.

Writing it generally: each component is present at [SPLIT]/3 mg/ml, giving ([SPLIT]/3) divided by 3367.9 and multiplied by 1000 millimolar for the GRF analogue, and ([SPLIT]/3) divided by 711.9 and multiplied by 1000 millimolar for ipamorelin. At an equal 7.5 plus 7.5 milligram split that is 2.5 mg/ml each, which works out to 0.742 mM and 3.51 mM. The molar ratio in the cartridge is then 4.7 to 1 in favour of ipamorelin, purely because it is the smaller molecule. Anyone quoting cjc 1295 ipamorelin 15mg as though it described a defined ratio is quoting a mass, not a stoichiometry.

Against published assay concentrations the fill is enormous. Raun and colleagues (1998) measured an ipamorelin EC50 of 1.3 plus or minus 0.4 nanomolar in rat pituitary cells, so 3.51 mM is about 2.7 million-fold above it, and the plasma SC50 of 214 nanomoles per litre modelled by Gobburu and colleagues (1999) is about 16,000-fold below the cartridge concentration. Reaching a 10 nanomolar working solution requires a serial dilution of roughly 350,000-fold. The randomised ipamorelin trial of 2014 gave 0.03 mg/kg intravenously, which is 2.1 mg for a 70 kg participant, so one device holds about seven times that quantity of combined peptide.

CJC 1295 Ipamorelin Pen vs Vial: What Does the Format Suit?

The cjc 1295 ipamorelin pen vs vial question is unusual because the blend is already a compromise: a vial lets a researcher reconstitute two separate lyophilized components and set the ratio, and a device fixes both the ratio and the buffer at manufacture.

That is the real trade here, and it is not the usual one. PrymaLab lists the 10mg lyophilized blend vial and the components separately, as CJC-1295 (No DAC) 10mg and ipamorelin 10mg. Buying the components separately is the only route to a chosen molar ratio, and any experiment that varies the ratio has to take it. The device answers a different question, which is repeated equivalent draws of one fixed composition with no reconstitution error, the trade the pen versus vial article covers in general.

The clock argument matters more here than for a stable tetrapeptide. The only solution figure on record for either component is 2 to 3 weeks at 4 degrees for ipamorelin, from a supplier statement, and a dry cake has no such clock running until diluent goes in. Work spanning more than a few weeks from the fill date has a real reason to prefer a vial. The preloaded autoinjector category page covers graduation resolution and cold-chain history.

What the CJC 1295 Ipamorelin Pen Record Does Not State

Five values are missing, and the first of them is unusual for a peptide product: the per-component split, the formulation pH, the excipient system, the fill date, and any stability figure for the mixture.

The split is the one with no substitute. Fifteen milligrams combined can be 7.5 plus 7.5, or 10 plus 5, or any other pair, and each gives different molar concentrations and different arithmetic downstream. Every per-component figure on this page is written as [SPLIT] for that reason, and the equal-split example is an illustration rather than a specification.

The pH decides both the isomerisation rate at Asp3 and whether the histidine stays protonated enough to keep the ipamorelin acetate soluble at 5 mg/ml. A cationic 29-mer plus a hydrophobic pentapeptide is exactly the pair a surfactant would be protecting from adsorption, and if one is present its peroxide content becomes a question for the histidine. The fill date sets the age of a solution whose only stability reference is 2 to 3 weeks at 4 degrees for one of its two components. Confirm all five against certificate of analysis.

Verifying the CJC 1295 Ipamorelin Pen Before Use

A two-component solution needs a chromatographic method that resolves both peaks and their degradants, which is a materially harder analysis than for a single peptide and the main practical cost of buying the blend as a liquid.

Inspect the solution against a white background before each draw: clear, colourless and free of particulate. Haze is worth taking seriously here, since ipamorelin free base is practically insoluble and a pH drift that deprotonates the histidine could bring material out of solution. Let the cartridge reach ambient temperature before actuating, and verify delivered volume gravimetrically once per device.

Ultraviolet detection works here in a way it does not for the short acidic bioregulators. The GRF analogue carries Tyr1 and Tyr10 and absorbs at 280 nanometres; ipamorelin’s naphthalene ring absorbs to about 320, which gives a second channel separating the components by spectrum as well as retention time. Mass spectrometry sees the histidine oxidation product at plus 16 daltons above 711.9 and misses isoaspartate at Asp3, which sits on the 3367.9 parent mass. A shallow reversed-phase gradient against a same-day reference reconstituted from lyophilized material resolves that isomer, and it is the measurement worth paying for on a device several weeks into use.

What Does the Literature Actually Report?

Nothing has been published on the two peptides together in any species, the no-DAC GRF analogue has no human study of any kind, and the human data that circulate under the CJC-1295 name belong to the DAC conjugate, a different molecule with a different half-life.

Jette and colleagues (2005) identified CJC-1295 as a long-acting GRF analogue, showing in rats that the albumin-binding conjugate remained detectable beyond 72 hours and produced a four-fold higher growth hormone area under the curve than hGRF(1-29). Teichman and colleagues (2006) ran two randomised, placebo-controlled, double-blind ascending-level studies of 28 and 49 days in healthy adults aged 21 to 61; a single subcutaneous injection raised growth hormone two to ten-fold for at least 6 days and IGF-1 1.5 to three-fold for 9 to 11 days, with no serious adverse reactions reported. The 5.8 to 8.1 day half-life quoted everywhere belongs to that conjugate, and nobody has measured the half-life of the no-DAC peptide in humans.

Ipamorelin has a fuller pharmacology file and a failed efficacy trial. Raun and colleagues (1998) reported an EC50 of 1.3 plus or minus 0.4 nanomolar in rat pituitary cells, an ED50 of 80 plus or minus 42 nanomoles per kilogram in rats and 2.3 in swine, and no release of adrenocorticotropic hormone or cortisol at 200-fold the growth hormone ED50. Gobburu and colleagues (1999) infused it intravenously over 15 minutes in 8 healthy men per level across 4.21 to 140.45 nanomoles per kilogram, reporting a terminal half-life near 2 hours, clearance of 0.078 litres per hour per kilogram and a growth hormone peak at 0.67 hours. The 2014 double-blind placebo-controlled trial registered as NCT00672074 enrolled 114 evaluable patients after bowel resection and missed its primary endpoint, 25.3 hours against 32.6 hours to first tolerated solid meal, p equal to 0.15. Development was discontinued. The site’s comparison of sermorelin, ipamorelin and tesamorelin sets out how the three differ.

Unstudied: the no-DAC peptide in humans, subcutaneous ipamorelin pharmacokinetics, the pair together in any species, immunogenicity, reproductive toxicity, and the stability of the mixture.

What Is the Safety and Regulatory Position?

Neither substance is approved anywhere, both sit in FDA Category 2 of the interim 503A bulk drug substances list, an advisory committee voted against both in late 2024, and both classes are prohibited in sport at all times.

FDA placed CJC-1295 and ipamorelin in Category 2 on 29 September 2023, and ipamorelin acetate appears on the 503B Category 2 list as well, on a page updated 22 April 2026, citing immunogenicity and adverse-event concerns. The Pharmacy Compounding Advisory Committee reviewed ipamorelin on 29 October 2024 and five forms of CJC-1295 on 4 December 2024; FDA recommended against both and the committee voted with that recommendation, with the tallies not retrieved for this page. Reviewers in December 2024 also called the inconsistent naming of CJC-1295 substances a safety risk in itself, since one trade name covers both the albumin-binding conjugate and the unconjugated analogue. Neither substance may be used in 503A compounding. WADA class S2 names growth hormone releasing hormone analogues and growth hormone secretagogues as prohibited at all times, which should be confirmed against the current Prohibited List.

The reported adverse findings are worth stating exactly. For the DAC conjugate, the FDA transcript records adverse events in 94 percent of participants after a single injection, injection-site reactions in about 70 percent, and headache, diarrhoea and flu-like symptoms. The same transcript records the unpublished 12-week phase 2 study in 192 patients with HIV-associated lipodystrophy, which ended after one participant died of myocardial infarction following the eleventh weekly injection, attributed to pre-existing coronary disease. For ipamorelin there are two non-serious reports in the FDA adverse event reporting system, and FDA raised ghrelin-pathway concerns covering behavioural reinforcement and developmental toxicity. None of that has been characterised for the unconjugated analogue or for the two peptides together.

How Do the Two Peptides in This Blend Differ Mechanically?

They work on separate receptors, which is the whole argument for combining them. The GRF component, also sold as mod GRF 1-29, is a GHRH analog: it binds the GHRH receptor on pituitary somatotrophs and triggers the same signalling that endogenous growth-hormone-releasing hormone triggers. Ipamorelin is a gh secretagogue of the other kind, a selective ghrelin receptor agonist acting at GHS-R1a, the same receptor hexarelin and the growth-hormone-releasing peptide series occupy.

Because the two receptors converge on the same cell, agonism at both produces a larger release than either alone, and the literature on GHRH plus a ghrelin receptor agonist in combination supports that synergy for the class. What follows is a change in the shape of the gh pulse rather than a change in total daily output. GH is released in bursts, somatostatin sets the trough between them, and a secretagogue given during a trough produces a pulse where none was due. Growth hormone secretion in this pattern is still pulsatile, and the pituitary gland retains its own feedback control, which is the stated attraction of the approach over administering human growth hormone directly.

The DAC distinction matters for anyone comparing products. Drug affinity complex is the maleimide group on full CJC-1295 that binds covalently to serum albumin and extends the half-life from minutes to about a week. This device carries the no-DAC version, so its action is short and its gh pulses are discrete. A blend built on the DAC version behaves differently and its data cannot be read across.

What Do IGF-1 and the Downstream Markers Actually Show?

IGF-1 is the integrator. Growth hormone itself is released in short bursts and a single blood draw catches whatever part of a pulse happened to be running, so serum GH is close to uninterpretable on its own. The liver converts sustained GH exposure into IGF-1, which circulates bound to binding proteins with a half-life of hours, so IGF-1 is what studies of any gh secretagogue actually measure. A compound that raises GH pulses without raising IGF-1 has not produced a sustained effect.

The endpoints below IGF-1 are where the evidence thins sharply. Protein synthesis, lean mass, muscle growth, fat metabolism, fat loss and body composition are the outcomes this class is marketed on, and muscle growth is the one most often assumed, and the human trials that measured them used recombinant growth hormone or, in the case of tesamorelin, an approved GHRH analog with registrational data. No trial of this two-peptide blend has measured any of them. Claims about tissue repair, sleep quality or anti-aging effects from this combination rest on the class literature and on the mechanism, not on studies of the product. The anti-aging framing in particular comes from the recombinant growth hormone literature of the 1990s and was not generated by any secretagogue trial.

What Side Effects Are Documented for This Class?

The documented ones belong to the individual compounds and to growth hormone excess generally. Water retention is the most consistent finding across GH secretagogue trials, presenting as peripheral oedema and joint discomfort, and it is dose-related. Flushing at the injection site and transient warmth are reported for GHRH analogs specifically. Carpal tunnel symptoms and reduced insulin sensitivity appear in the recombinant GH literature at higher exposures.

Selectivity is where the two halves of this blend differ. Agonists at that receptor can raise prolactin and cortisol through the same receptor population, and GHRP-6 and GHRP-2 both do so measurably. Ipamorelin was designed to avoid that, and the published comparisons report it as the most selective member of the series, with little effect on prolactin or cortisol at doses that release growth hormone. That selectivity is the reason it appears in blends of this type rather than the older secretagogues.

None of this constitutes a safety profile for the product in the cartridge. No side effects have been catalogued for this specific blend at this specific concentration, and the counter-ion, excipient system and pH are all unstated on the record. Both peptides are prohibited in sport at all times under the WADA S2 category, which is a separate matter from safety and applies to any competing athlete regardless of formulation.

What Do Peptide Pens Change About Handling?

They remove a step and add a constraint. A vial of research peptides arrives dry and is reconstituted with bacteriostatic water at the bench, so the concentration is chosen by the person doing the work and the dry material can be stored for a long time. Peptide pens arrive filled, so no reconstitution is done and the concentration is fixed by the manufacturer. The material must be refrigerated from arrival, and once a peptide is in water it is ageing whether or not it is refrigerated.

The trade is worth stating plainly for a blend. Two synthetic peptide components in one reservoir share a pH, a buffer and a fill date, and the pH that suits one may not be the pH that suits the other. In a vial format they could be reconstituted separately and combined immediately before use. Peptide pens make that impossible by design, which is the cost of the convenience.

Ask the supplier for the lot-specific CoA covering both components, with purity for each peptide separately and an accurate mass for each. Peptide therapy providers sell devices like this one as ready-to-use treatments. This is not that: it is a research preparation and no regulator has approved either component. Peptide therapy protocols circulating for this combination are not derived from published trials of it, and no peptide therapy clinic has published outcome data on the pairing.

Published Literature

Each entry was checked against the publisher record or a primary index. None concerns the blend or the pen format, on which nothing has been published.

1. Jette L, Leger R, Thibaudeau K, et al. Endocrinology. 2005;146(7):3052-3058. DOI: 10.1210/en.2004-1286
2. Teichman SL, Neale A, Lawrence B, et al. J Clin Endocrinol Metab. 2006;91(3):799-805. DOI: 10.1210/jc.2005-1536 PMID: 16352683
3. Raun K, Hansen BS, Johansen NL, et al. Eur J Endocrinol. 1998;139(5):552-561. DOI: 10.1530/eje.0.1390552 PMID: 9849822
4. Gobburu JV, Agerso H, Jusko WJ, et al. Pharm Res. 1999;16(9):1412-1416. DOI: 10.1023/A:1018955126402
5. Friedman AR, Ichhpurani AK, Brown DM, et al. Int J Pept Protein Res. 1991;37(1):14-20. DOI: 10.1111/j.1399-3011.1991.tb00727.x

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