What Is ARA-290 (Cibinetide)? Peptide Profile

Cover illustration: AI-generated editorial artwork. Conceptual only; not an exact molecular structure, actual laboratory result or evidence of clinical effects.

ARA-290, assigned the name cibinetide, is an 11-amino-acid peptide designed from a specific structural region of erythropoietin. The design question behind it is unusually clean, which makes it a good entry point into receptor-selectivity reasoning.

For laboratory research use only. The research materials supplied by HealthyWelness are not approved medicines, foods or cosmetics and are not for human or veterinary use. This article summarises published research and is not medical advice.

Key points

Length: 11 amino acids, derived from the helix B surface of EPO.
Named target: the innate repair receptor — EPOR paired with the beta-common receptor (CD131).
Two names: ARA-290 (development code) and cibinetide (INN) are the same compound.
Published models: colitis, diabetic wound healing, ischaemic retina; clinical work reported in small fibre neuropathy.
Not erythropoietin, and not studied as a haematopoietic agent.

The design problem it addresses

Erythropoietin is best known for driving red blood cell production. A separate body of work described tissue-protective and anti-inflammatory effects of EPO that appeared not to depend on that same activity. If the two functions run through different receptor configurations, then a molecule engaging only one of them becomes possible.

The published model is that erythropoiesis proceeds through the homodimeric EPO receptor, while tissue protection proceeds through a heteromer of EPOR and the beta-common receptor, referred to in this literature as the innate repair receptor. ARA-290 was constructed from the helix B surface — a face of the EPO molecule reported to be involved in the second interaction but not the first.

This is why the literature describes it as a “non-haematopoietic erythropoietin mimetic”. The phrase is a statement about which receptor configuration is engaged, not a claim of superiority.

Published research

Study	Model	Reported observation
Nairz et al., 2017	Experimental colitis, mice	Dampened innate immune cell function, with an ameliorated disease course
Bitto et al., 2018	Genetically diabetic mice, wound model	Improvement in impaired wound healing attributed to activation of the EPOR / beta-common complex
O’Leary et al., 2019	Ischaemic retina, endothelial colony-forming cells	Enhanced vasoreparative potential of the transplanted cells

Three independent disease contexts with a common theme: the reported effects concern inflammatory tone and tissue repair rather than any single organ system. That pattern is consistent with the stated receptor rationale, which is part of why the compound is used as a tool to probe it.

Why the receptor claim matters for interpretation

Much of the interest in ARA-290 rests on a negative claim — that it does not engage the erythropoietic receptor configuration. Negative claims are harder to establish than positive ones, and a study designed to show tissue protection will not necessarily be designed to detect a small haematological signal. When reading any individual paper, it is worth checking whether haematocrit or reticulocyte endpoints were measured at all, rather than assuming receptor selectivity was re-confirmed each time.

Handling in the lab

Supplied lyophilized; store the sealed vial at −20 °C, protected from light and moisture.
An 11-residue peptide of this composition is normally water-soluble; add diluent down the vial wall rather than directly onto the cake, and swirl rather than shake.
Short peptides offer little buffering against surface losses at low concentrations — consider a carrier protein in dilute working solutions for cell work.
Store reconstituted material at 2–8 °C and aliquot to avoid repeated freeze–thaw. See storing reconstituted peptides.
Work out concentrations with the peptide reconstitution calculator.

Our ARA-290 (cibinetide) research material is supplied with HPLC purity and mass spectrometry data per lot.

Why an 11-residue peptide is a hard reagent

Length has consequences that are easy to underestimate. Three in particular affect work with this peptide:

Rapid clearance. Short peptides are filtered and degraded quickly, so a sustained effect reported in an animal model raises a legitimate question about what mediates it after the peptide itself has gone. Downstream signalling, rather than continued receptor occupancy, is the usual proposed answer.
Adsorptive losses. At nanomolar working concentrations, a meaningful fraction can be lost to tube and plate surfaces. This is one reason reported active concentrations vary between laboratories using nominally identical protocols.
Conformational ambiguity. An 11-residue peptide derived from a helix within a folded protein may not adopt that helix in isolation. Whether it does is relevant to how faithfully it reproduces the parent interaction.

None of these undermines the published work. They are the reasons a positive control demonstrating activity on the day is worth including in any experiment with this class of reagent.

Open questions

How complete is the separation between repair and erythropoietic signalling across tissues and exposure durations?
What is the half-life of an 11-residue peptide in circulation, and how does that square with the reported effect durations?
Do the reported anti-inflammatory effects generalise beyond the specific models published?

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Frequently asked questions

What is ARA-290?

ARA-290, also known as cibinetide, is a synthetic 11-amino-acid peptide whose sequence corresponds to a region of the helix B surface of erythropoietin. It is studied as a ligand for the innate repair receptor, a complex of EPOR and the beta-common receptor.

Is ARA-290 the same as erythropoietin?

No. It is derived from a structural region of erythropoietin but is a short peptide rather than the full glycoprotein. The published rationale is that it engages the tissue-protective receptor complex without engaging the receptor configuration associated with red blood cell production.

What is the innate repair receptor?

A heteromeric receptor complex formed by the erythropoietin receptor (EPOR) and the beta-common receptor (CD131). It is described in the literature as mediating tissue-protective and anti-inflammatory signalling distinct from erythropoiesis.

What models has ARA-290 been studied in?

Published work includes an experimental colitis model, a diabetic wound-healing model in mice, and work on endothelial colony-forming cells in the ischaemic retina. Clinical trial activity has also been reported in sarcoidosis-related small fibre neuropathy.

What does the name cibinetide refer to?

Cibinetide is the international nonproprietary name assigned to the compound. ARA-290 is the earlier development code; the two refer to the same peptide.

References

Nairz M, et al. Cibinetide dampens innate immune cell functions thus ameliorating the course of experimental colitis. Sci Rep. 2017. PMID: 29026145 https://pubmed.ncbi.nlm.nih.gov/29026145/
Bitto A, et al. Activation of the EPOR-beta common receptor complex by cibinetide ameliorates impaired wound healing in mice with genetic diabetes. Biochim Biophys Acta Mol Basis Dis. 2018. PMID: 29223734 https://pubmed.ncbi.nlm.nih.gov/29223734/
O'Leary OE, et al. The vasoreparative potential of endothelial colony-forming cells in the ischemic retina is enhanced by cibinetide, a non-hematopoietic erythropoietin mimetic. Exp Eye Res. 2019. PMID: 30876881 https://pubmed.ncbi.nlm.nih.gov/30876881/