ARA-290 (Cibinetide) Peptide: Research Guide, Handling Math, and How to Vet a COA

ARA-290, known by the drug name cibinetide, is a research-use-only 11-amino-acid peptide engineered from a surface region of erythropoietin’s (EPO) helix B domain. It was built to switch on the proposed “innate repair receptor” (a heterocomplex of the EPO receptor and the beta-common receptor, CD131) while deliberately not stimulating red-blood-cell production the way EPO does. In the literature it has been studied mostly in preclinical neuropathic-pain and tissue-protection models, alongside a few small human trials in sarcoidosis-associated small-fiber neuropathy and type 2 diabetes. It is not an approved drug, has no established human use, and the only thing separating a genuine research vial from expensive filler is a named-lab COA you can independently verify before you pay.

Published 2026 - For research use only (RUO). Nothing here is medical advice, a dosing protocol, or a human-use recommendation. ARA-290 (cibinetide) is an investigational compound and is not an approved drug. The concentration math below is standard laboratory reconstitution arithmetic for handling a research sample, not an instruction to administer anything to a person or animal.

In a hurry? Jump to how Pepora scores on the checklist →

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What ARA-290 actually is

ARA-290 is a short, linear peptide of 11 amino acids taken from the exposed surface of helix B of erythropoietin. In the original research it is called the helix B surface peptide (pHBSP); developed as a drug candidate by Araim Pharmaceuticals, it carries the international nonproprietary name cibinetide and the code ARA-290. The cibinetide form has a modified (pyroglutamate) N-terminus. It is a defined synthetic sequence, not a proprietary blend and not a molecule you can eyeball for identity, which is exactly why the mass-spec line on a COA matters.

Two facts frame everything else:

1. It is derived from EPO but is non-erythropoietic. The foundational work showed that peptides mimicking the folded surface of erythropoietin retain the tissue-protective side of EPO signaling while losing the ability to raise red-cell mass (Brines et al., PNAS, 2008, PMID 18676614). A vendor that markets ARA-290 as an “EPO alternative” for blood building has the pharmacology backwards.
2. The label is a claim; the COA is the measurement. A vial stamped “10 mg / 99%” states a manufacturing target. The only number that reflects what is physically in the glass is a lot-matched Certificate of Analysis showing HPLC purity and mass-spec identity for that specific lot. The exact molecular weight (roughly the 1.2 to 1.3 kDa range for an 11-mer) should be confirmed on the report rather than taken from a product page.

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How it is thought to work: the innate repair receptor

The mechanism reported across the literature is selective activation of a receptor complex, not a generic “healing” effect. Erythropoietin’s red-cell activity runs through a homodimer of the EPO receptor (EPOR). Tissue protection is attributed instead to a distinct heterocomplex of EPOR and the beta-common receptor (CD131, also written beta-cR), described in the reviews as the innate repair receptor (IRR) (Collino et al., Pharmacol Ther, 2015, PMID 25728128). ARA-290 was engineered to bind the IRR without triggering the homodimeric EPOR, which is the design reason it does not raise red-cell counts or carry EPO’s clot-promoting profile in the models tested.

The strongest mechanistic evidence for the receptor dependence comes from a knockout study: in rats, ARA-290 produced long-lasting relief in a neuropathic-pain model, and that effect disappeared in beta-common receptor knockout mice (Swartjes et al., Anesthesiology, 2011, PMID 21873879). When removing the receptor removes the readout, the pathway attribution is doing real work rather than hand-waving. This is a described research mechanism, not a demonstrated clinical effect.

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What the research actually covers

The framing below reports what published laboratory and clinical studies examined. None of it is a use instruction, and the human studies are small and early. Read them as “this is the shape of the evidence,” not “this works in people.”

Preclinical neuropathy and tissue-protection models

Most of the ARA-290 file is preclinical. Beyond the receptor-knockout pain study above, a rat neuritis model found ARA-290 reversed mechanical allodynia, that is, heightened sensitivity to a normally non-painful stimulus (Pulman et al., Neuroscience, 2013, PMID 23262243). The recurring theme across the EPO-derived-peptide literature is protection of nerve and other tissue under stress through the beta-common-receptor arm, which is what motivated moving a candidate into small human studies.

Small human studies

Cibinetide has been through small, early-phase clinical trials, primarily in sarcoidosis-associated small-fiber neuropathy and in type 2 diabetes. Reporting what those trials measured, not endorsing any use:

• In a controlled study of sarcoidosis patients with small-nerve-fiber loss, investigators reported improved patient-reported neuropathic symptom scores and an increase in corneal nerve fiber density, a structural imaging measure of small-fiber integrity, over the study window (Dahan et al., Mol Med, 2013, PMID 24136731; reviewed in van Velzen et al., Expert Opin Investig Drugs, 2014, PMID 24555851). A follow-up analysis with corneal confocal microscopy again reported improved corneal nerve fiber abundance in this population (Culver et al., Invest Ophthalmol Vis Sci, 2017, PMID 28475703).
• A separate small study in type 2 diabetes reported changes in some metabolic parameters alongside neuropathic-symptom readouts over a 28-day window (Brines et al., Mol Med, 2015, PMID 25387363).

What the evidence does not show

There is no approved indication and no large confirmatory trial establishing efficacy or safety for ARA-290 as a treatment. The human studies are small, short, and early-phase; corneal nerve fiber density is a surrogate structural marker, not a clinical outcome by itself. Anyone reading a rodent allodynia result or a 28-day surrogate change as a settled human therapy is overstating what exists. As a non-approved pharmacological substance, cibinetide would fall under WADA’s S0 (Non-Approved Substances) category, so any research subject in tested sport is prohibited from having it present.

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Reconstitution and handling math (lab-prep only)

This is concentration arithmetic for preparing a laboratory reference solution from a lyophilized research vial. It tells you how much peptide sits in a given volume of solvent. It is not a dosing schedule and says nothing about route of administration.

The only formula you need:

concentration (mg/mL) = peptide mass in the vial (mg) ÷ volume of bacteriostatic water added (mL)

ARA-290 is commonly sold as a 10 mg vial (some vendors offer 16 mg); scale the table linearly for a different total mass. Using a representative 10 mg vial reconstituted with bacteriostatic water:

Bacteriostatic water added	Concentration	Peptide in a 0.10 mL aliquot
1 mL	10 mg/mL	1.0 mg
2 mL	5 mg/mL	0.5 mg
3 mL	~3.33 mg/mL	~0.33 mg
5 mL	2 mg/mL	0.2 mg

Handling notes grounded in the chemistry, not in any use case:

• Solvent. Bacteriostatic water (sterile water with 0.9% benzyl alcohol) is the usual multi-draw diluent because the preservative tolerates repeated needle entry over a storage window. That is a reconstitution detail, not a route claim.
• Technique. Add the water slowly down the inside wall and swirl gently; do not spray it onto the powder cake and do not shake, since short peptides are shear-sensitive and foaming makes the meniscus hard to read.
• Trust the COA, not the cap. If a lot-matched COA reports 9.6 mg of measured peptide, the true concentration is 9.6 divided by your solvent volume, not 10. Without lot-matched testing, every figure in the table above is a guess.
• Storage. Keep lyophilized powder frozen and desiccated until use; reconstituted solution goes refrigerated (2 to 8 °C) under sterile conditions. Scale the table for your actual vial mass.

For why the numbers on a report line up (or do not), see how to read a peptide COA.

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How to vet a vendor COA for ARA-290

The research-peptide market is thin on accountability, so rank vendors only on things you can independently verify before you pay. Marketing adjectives (“pharmaceutical-grade,” “99%+,” “trusted”) are not evidence. These five signals are, and they map directly onto the classic peptide vendor red flags.

Verification signal	What the gold standard looks like	Why it matters
Named third-party lab	An independent lab named on the COA (e.g., Freedom Diagnostics, Janoshik)	An unnamed “in-house lab” is not third-party testing
Independently verifiable COA	A report you can re-pull at the lab’s own site (e.g. by accession number)	If you cannot re-check it at the source, a screenshot proves little
HPLC + mass spec	HPLC for purity and mass spec for identity/mass	HPLC alone does not confirm the molecule is actually the 11-mer you ordered
Report visible pre-purchase	You can read the actual COA before checkout	“Email us for the COA after you order” defeats the point
Ships from the US	Truthful, checkable shipping origin	Vague origin plus vapor checkout is a classic red flag

Because ARA-290 is a specific defined sequence, the mass-spec line is not optional. HPLC can show a clean single peak for the wrong molecule; only the mass confirms you are holding the ~1.2 to 1.3 kDa helix B surface peptide and not a cheaper substitute. Hold every vendor to all five signals, including the one recommended below. For the wider market context on which single-peptide vendors publish real reports, see the best peptide sources on Reddit for 2026 and the Amino Asylum shutdown alternative breakdown.

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How Pepora scores

Pepora uses Freedom Diagnostics, a US lab running HPLC, UV, and mass spectrometry, for its third-party testing, and each report it posts is verifiable by accession number through the Certificate of Analysis lookup at FreedomDiagnosticsTesting.com, so you confirm the figures at the lab’s own source instead of trusting a screenshot. The mechanism is the whole point: a posted Freedom report carries an accession number you re-enter at the lab’s portal to read the HPLC and mass-spec results yourself, rather than taking a purity figure on faith from a product page.

Being honest about coverage: only 3 to 4 SKUs currently carry a live Freedom Diagnostics COA, and third-party testing is still expanding across the rest of the catalog. ARA-290 specifically may sit in that expanding-coverage bucket rather than already having a posted Freedom report, so do not assume. Check the live COA on the exact ARA-290 SKU before you buy, and if the report for that lot is not yet posted and independently verifiable, hold the purchase and apply the same five-point checklist you would use on any other vendor. The point of this site is that the rule does not bend for the house pick.

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The disclosed pick

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FAQ

What is ARA-290 (cibinetide)? ARA-290, also called cibinetide, is a research-use-only 11-amino-acid linear peptide engineered from a surface region of erythropoietin’s helix B domain. It was designed to activate the innate repair receptor without stimulating red-blood-cell production, and it has been studied in preclinical neuropathy and tissue-protection models plus a handful of small human trials. It is not an approved drug.

How is ARA-290 thought to work? In the published literature it is described as a selective agonist of the innate repair receptor (IRR), a proposed heterocomplex of the erythropoietin receptor (EPOR) and the beta-common receptor (CD131). Because it does not engage the homodimeric EPOR that drives erythropoiesis, it lacked the red-cell-stimulating and clot-promoting activity of erythropoietin in the models studied. This is a mechanism described in research, not a claimed effect in people.

Is ARA-290 the same as EPO? No. It is derived from erythropoietin’s tertiary structure but is non-erythropoietic. The foundational 2008 PNAS work showed peptides taken from the folded surface of EPO retained tissue-protective signaling while losing the ability to raise red-cell mass. Treat any vendor that markets it as an EPO substitute as scientifically confused.

How do you reconstitute an ARA-290 vial? As lab-prep concentration math only: divide the milligrams of powder stated on the lot’s COA by the millilitres of bacteriostatic water you add. A representative 10 mg vial reconstituted with 2 mL gives 5 mg/mL; with 5 mL it gives 2 mg/mL. Use the COA-measured mass, not the label, and treat this as reconstitution arithmetic for a research sample, not a dosing instruction.

Is ARA-290 FDA-approved or legal to use in humans? No. Cibinetide is an investigational compound that has been through small Phase 2 trials but is not approved by the FDA for any use. It is sold and handled research-use-only. As a non-approved pharmacological substance it would fall under WADA’s S0 (Non-Approved Substances) category, so anyone in tested sport should treat it as prohibited.

How do I verify an ARA-290 COA is real? Confirm the testing lab is named (for example Freedom Diagnostics or Janoshik) rather than an anonymous in-house bench, then re-pull the report at the lab’s own source: for Freedom Diagnostics, look it up by accession number at FreedomDiagnosticsTesting.com. Require HPLC purity plus a mass-spec identity check, and confirm the lot number on the report matches the vial in your hand, since a COA for a different batch tells you nothing about your material.

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References

1. Brines M, Patel NSA, Villa P, et al. Nonerythropoietic, tissue-protective peptides derived from the tertiary structure of erythropoietin. Proc Natl Acad Sci U S A. 2008;105(31):10925-10930. PMID: 18676614. https://pubmed.ncbi.nlm.nih.gov/18676614/
2. Swartjes M, Morariu A, Niesters M, et al. ARA290, a peptide derived from the tertiary structure of erythropoietin, produces long-term relief of neuropathic pain: an experimental study in rats and beta-common receptor knockout mice. Anesthesiology. 2011;115(5):1084-1092. PMID: 21873879. https://pubmed.ncbi.nlm.nih.gov/21873879/
3. Pulman KG, Smith M, Mengozzi M, Ghezzi P, Dilley A. The erythropoietin-derived peptide ARA290 reverses mechanical allodynia in the neuritis model. Neuroscience. 2013;233:174-183. PMID: 23262243. https://pubmed.ncbi.nlm.nih.gov/23262243/
4. Dahan A, Dunne A, Swartjes M, et al. ARA 290 improves symptoms in patients with sarcoidosis-associated small nerve fiber loss and increases corneal nerve fiber density. Mol Med. 2013;19(1):334-345. PMID: 24136731. https://pubmed.ncbi.nlm.nih.gov/24136731/
5. van Velzen M, Heij L, Niesters M, et al. ARA 290 for treatment of small fiber neuropathy in sarcoidosis. Expert Opin Investig Drugs. 2014;23(4):541-550. PMID: 24555851. https://pubmed.ncbi.nlm.nih.gov/24555851/
6. Brines M, Dunne AN, van Velzen M, et al. ARA 290, a nonerythropoietic peptide engineered from erythropoietin, improves metabolic control and neuropathic symptoms in patients with type 2 diabetes. Mol Med. 2015;20(1):658-666. PMID: 25387363. https://pubmed.ncbi.nlm.nih.gov/25387363/
7. Collino M, Thiemermann C, Cerami A, Brines M. Flipping the molecular switch for innate protection and repair of tissues: Long-lasting effects of a non-erythropoietic small peptide engineered from erythropoietin. Pharmacol Ther. 2015;151:32-40. PMID: 25728128. https://pubmed.ncbi.nlm.nih.gov/25728128/
8. Culver DA, Dahan A, Bajorunas D, et al. Cibinetide improves corneal nerve fiber abundance in patients with sarcoidosis-associated small nerve fiber loss and neuropathic pain. Invest Ophthalmol Vis Sci. 2017;58(6):BIO52-BIO60. PMID: 28475703. https://pubmed.ncbi.nlm.nih.gov/28475703/

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Full disclosure: This page is operated by / affiliated with Pepora (peporalabs.com), a research-peptide vendor. It is affiliate education, not independent journalism: we recommend our own store and earn a commission on purchases made with code SINGLES15. We rank strictly on lab-verifiable criteria (named third-party lab, independently verifiable third-party COAs, HPLC and mass spec) so you can check the claims yourself. Research use only. Not for human or veterinary use. ARA-290 (cibinetide) is an investigational compound and is not an approved drug. Nothing here is medical advice, a dosing protocol, or a human-use recommendation.