ARA-290 · Research brief

ARA-290 (Cibinetide): Research Overview and Handling Guide

Real Peptides Research TeamEditorial

Updated September 5, 202611 min read

53 WORDS

Short answer

ARA-290, also called cibinetide, is a synthetic 11-amino-acid peptide derived from a structural region of the erythropoietin molecule. It was engineered to retain tissue-protective signaling while lacking erythropoiesis-stimulating activity. Laboratory research examines its interaction with the innate repair receptor and its effects in models of nerve injury, metabolic stress, inflammation, and tissue repair.

Key takeaways

ARA-290 (cibinetide) is a synthetic 11-amino-acid peptide derived from a structural region of erythropoietin, engineered to lack erythropoiesis-stimulating activity.
Its reported mechanism centers on the innate repair receptor, described as a heteromeric complex of the EPO receptor and the beta-common receptor (CD131), rather than the classical homodimeric EPO receptor.
Published work spans neuropathy and small-fiber models, islet transplantation, renal and cardiac injury models, bone density in mice, neuroinflammation, and a Phase 2 ophthalmology trial; evidence remains preliminary and largely preclinical.
ARA-290 is not FDA-approved for any of the applications discussed on this page and is supplied by Real Peptides for laboratory research use only.
Lyophilized peptide is typically stored cold and protected from light and moisture; reconstituted material is far less stable and is generally treated as short-lived under refrigeration.
Supplier evaluation rests on batch-specific third-party COAs with HPLC purity chromatograms, mass spectrometry identity confirmation, and traceable lot numbers.

What ARA-290 Is and Where It Came From

Erythropoietin (EPO) is best known as the hormone that drives red blood cell production. Over the past two decades, however, investigators observed that EPO also produced tissue-protective and anti-inflammatory effects in injury models — effects that appeared to be mediated by a different receptor arrangement than the one responsible for erythropoiesis. That observation created an obvious design problem: the hematopoietic activity of EPO carries its own biological consequences, which complicates the study of the tissue-protective arm in isolation.

ARA-290 was the answer to that problem. It is a short linear peptide corresponding to a solvent-exposed region of the EPO helix B — the face of the molecule that does not participate in binding the classical homodimeric EPO receptor. Because it reproduces that surface without the rest of the protein scaffold, ARA-290 is described in the literature as non-erythropoietic: it is not reported to stimulate red cell production, while retaining affinity for the receptor complex associated with tissue protection.

The names can be confusing. ARA-290 and cibinetide are the same compound — ARA-290 is the development code, and cibinetide is the international nonproprietary name (INN) assigned later. "ARA290" without the hyphen refers to the same molecule. Papers use the terms interchangeably, and searching only one of them will miss a substantial portion of the literature.

Reported Mechanism of Action

The mechanism most consistently described for ARA-290 involves the innate repair receptor (IRR), characterized in the literature as a heteromeric complex formed by the EPO receptor and the beta-common receptor, CD131. This receptor complex is described as being upregulated on tissues under metabolic or inflammatory stress, rather than being constitutively abundant — which has led investigators to propose that ARA-290 signaling is conditional on the presence of injury.

Downstream, published work reports engagement of pathways associated with cell survival and inflammatory resolution. Reported readouts across models have included modulation of apoptotic signaling, reduction of oxidative stress markers, shifts in macrophage and monocyte phenotype, and dampening of pro-inflammatory cytokine output. Work published in Inflammation in 2023 described protective effects of ARA290 in a cisplatin-induced nephrotoxicity model with explicit attention to apoptosis and inflammation pathways, framing the receptor as the EPO/CD131 heteroreceptor.

Because the compound is small, synthetic, and structurally simple relative to EPO itself, it has also been used as a tool molecule — a way to interrogate IRR biology without the confound of erythropoiesis. That tool-compound role is a large part of why it appears across so many unrelated disease models.

What the mechanism does not appear to include

ARA-290 is not reported to raise hematocrit or hemoglobin in the way recombinant EPO does. It is not an anabolic agent, a growth hormone secretagogue, or a metabolic peptide in the sense those categories are usually used. Researchers evaluating it should expect readouts related to inflammation, nerve fiber integrity, and cellular stress rather than performance or body-composition endpoints.

What the Research Literature Examines

The published record is diverse but mostly early-stage. The organizing thread is tissue stress: nearly every model involves a tissue placed under chemical, ischemic, metabolic, or inflammatory insult.

Neuropathy and small-fiber biology

The most widely discussed research area is small-fiber neuropathy, particularly in the context of sarcoidosis and diabetes. Early clinical work has reported changes in patient-reported neuropathic symptom scores and in corneal nerve fiber measurements assessed by confocal microscopy. These studies have generally been small and exploratory, and the field has not converged on confirmatory outcomes. Evidence remains preliminary.

Islet biology and transplantation

Two 2020–2021 publications examined cibinetide in the context of pancreatic islet transplantation. Work in Cell Transplantation (2021) reported protection of isolated human islets under stressful culture conditions and improved engraftment in a model relevant to intraportal islet transplantation, and a 2020 Transplantation paper reported improvement of islet allograft function attributed to innate repair receptor ligation. Both are preclinical or ex vivo in scope.

Ophthalmology

A Phase 2 clinical trial of cibinetide in diabetic macular edema was published in the Journal of Clinical Medicine in 2020. Phase 2 work is hypothesis-testing rather than definitive, and results at this stage are best read as directional.

Chemotherapy-associated organ and genomic stress

Beyond the cisplatin nephrotoxicity work noted above, a 2020 paper in Toxicology in Vitro reported that ARA290 attenuated doxorubicin-induced genotoxicity and oxidative stress in an in vitro system. These models are relevant to the broader question of whether IRR ligation can uncouple cytotoxic drug efficacy from off-target tissue damage — an open question, not a settled one.

Neuroinflammation and CNS models

A 2022 paper in Brain, Behavior, and Immunity reported that early monocyte modulation by ARA 290 decelerated the progression of Alzheimer's-like pathology in a rodent model. This is an interesting mechanistic result about peripheral immune contributions to CNS pathology; it does not translate to clinical conclusions.

Bone

A 2021 paper in the International Journal of Molecular Sciences reported that cibinetide inhibited osteoclastogenesis in vitro and was associated with increased bone mineral density in mice — a finding that expanded the compound's apparent range beyond nerve and immune tissue.

Imaging and cardiac ischemia

A 2021 study in the Iranian Journal of Basic Medical Sciences described synthesis and evaluation of a technetium-99m DOTA-conjugated ARA-290 as a candidate SPECT tracer for targeting cardiac ischemic regions — an application that leverages the reported upregulation of the receptor complex in injured tissue rather than any therapeutic effect.

Research area	Model type reported	Maturity of evidence
Small-fiber neuropathy	Early clinical, exploratory	Preliminary; small cohorts
Islet transplantation	Ex vivo human islets, animal allograft	Preclinical
Diabetic macular edema	Phase 2 clinical	Hypothesis-testing stage
Chemotherapy-associated tissue stress	Rodent and in vitro	Preclinical
Neuroinflammation / AD-like pathology	Rodent model	Preclinical, mechanistic
Bone density / osteoclastogenesis	In vitro and mice	Preclinical
Ischemia imaging tracer	Radiolabeled conjugate	Early feasibility

Laboratory Handling

ARA-290 ships as a lyophilized (freeze-dried) white powder under vacuum or inert gas. In that state it is comparatively robust, but it is hygroscopic, and moisture is the primary enemy of long-term integrity. Standard laboratory practice is to allow a cold vial to equilibrate to ambient temperature before breaking the seal, which prevents condensation from forming on the interior surfaces.

Reconstitution in a research setting is typically performed with bacteriostatic or sterile water introduced slowly down the inner wall of the vial rather than directed at the powder cake. The vial is then swirled or left to dissolve rather than shaken, since mechanical agitation and foaming can denature short peptides at the air–liquid interface. Solvent volume is a matter of the individual laboratory's working-concentration requirements and is not prescribed here.

Storage practice generally follows two tiers:

Lyophilized material: stored cold, dry, and protected from light. Freezer storage is standard for extended holding periods; refrigeration is common for material in active use.
Reconstituted solution: markedly less stable. Solutions are typically kept refrigerated, protected from light, and treated as short-lived. Aliquoting into single-use portions reduces freeze–thaw cycling and repeated septum punctures.

Visual and analytical indicators that material may have degraded include cloudiness or particulates in a solution that was previously clear, discoloration of the powder cake, a collapsed or oily-looking cake, and — analytically — loss of peak area or the appearance of new peaks on re-analysis by HPLC. Laboratories that need certainty re-assay rather than infer from appearance.

Regulatory and Research-Use Status

ARA-290 (cibinetide) is not approved by the FDA for the treatment, prevention, or management of any of the conditions discussed on this page. It has moved through early clinical investigation in certain indications, but investigational status is not approval, and clinical-trial context is not equivalent to general availability.

Material supplied by Real Peptides is intended for research use only — in vitro work and laboratory investigation conducted by qualified personnel under appropriate institutional oversight. It is not a drug, not a dietary supplement, and not intended for human or veterinary administration, diagnostic procedures, or any household use. Nothing on this page constitutes medical advice or a protocol for use in people. Investigators working with animal models are responsible for their own IACUC or equivalent approvals; investigators working with human-derived tissue are responsible for the corresponding ethical approvals.

How Researchers Evaluate Supplier Quality

Peptide quality is not visible in the vial, so evaluation is documentary and analytical. The questions that matter most:

Is there a batch-specific COA, and is it third-party? A certificate that is not tied to the exact lot number on the vial in hand tells a researcher very little. Third-party analysis removes the obvious conflict of interest.
Does the COA include an actual HPLC chromatogram? A stated purity percentage without the trace is an assertion. The chromatogram shows peak shape, baseline behavior, and the size and position of impurity peaks — which matters more than a headline number.
Is identity confirmed by mass spectrometry? Purity says a sample is one thing; mass spec says which thing. For an 11-residue peptide, the observed mass should match the expected monoisotopic or average mass for the sequence. Purity without identity confirmation is incomplete.
Is the lot traceable? Lot numbers should be printed on the vial, reproduced on the COA, and retrievable from the supplier. Traceability is what makes it possible to reconcile an anomalous experimental result with a specific batch.
Is the presentation consistent? Uniform fill, intact lyophilized cake, sealed stoppers, and appropriate cold-chain handling are indirect but meaningful signals about process control.

Sophisticated laboratories also keep a retained sample of each lot. If results diverge unexpectedly between experiments run months apart, having archived material makes the reagent question answerable rather than speculative.

Where the Open Questions Are

Honest summary: ARA-290 has an unusually coherent mechanistic story and an unusually thin confirmatory evidence base. The gaps worth naming:

Receptor characterization. The innate repair receptor is defined largely functionally. Direct structural and binding characterization of the EPO receptor–CD131 complex remains less complete than the frequency of the term in the literature would suggest.
Dose–response and exposure relationships. The peptide is short and reported to clear rapidly, yet reported effects in several models outlast measurable exposure. How transient receptor engagement produces durable changes is not resolved.
Translation. Preclinical protection in rodent and in vitro models has repeatedly failed to translate for other tissue-protective agents. Whether ARA-290 escapes that pattern is unknown.
Breadth versus specificity. A compound reported to affect nerve fibers, islets, bone, kidney, and CNS immune cells is either engaging a genuinely general repair pathway or is being tested in models with a shared, less specific readout. Distinguishing these possibilities requires more rigorous negative controls than most published work has included.
Long-term consequences of chronic receptor engagement. Nearly all published work is short-term. What sustained IRR ligation does to immune surveillance or tissue remodeling has not been characterized.

For researchers, that combination — clear hypothesis, broad preclinical signal, unresolved translation — is precisely what makes the compound interesting to study rather than to conclude anything about.

Research-grade ARA-290 (Cibinetide): Real Peptides supplies ARA-290 (Cibinetide) for laboratory research with a published third-party Certificate of Analysis for every batch. Research use only.

Explore ARA-290 (Cibinetide) research on Real Peptides

The articles below go deeper on the questions researchers ask most about ARA-290 (Cibinetide).

Research timelines & mechanisms

Reconstitution, storage & handling

Buying & quality

ARA-290 Reddit Reviews Community — Real User Experiences

Stacks & comparisons

Research questions

Safety & side effects

Legal & regulatory

Is ARA-290 Legal to Purchase for Research? (2026 Guide)

References

Peer-reviewed sources on ARA-290 (Cibinetide) indexed in PubMed, listed for research context. Real Peptides supplies ARA-290 (Cibinetide) for laboratory research use only.

Mechanistic Approach for Protective Effect of ARA290, a Specific Ligand for the Erythropoietin/CD131 Heteroreceptor, against Cisplatin-Induced Nephrotoxicity, the Involvement of Apoptosis and Inflammation Pathways. Inflammation, 2023. PMID 36085231. doi:10.1007/s10753-022-01737-7
Early monocyte modulation by the non-erythropoietic peptide ARA 290 decelerates AD-like pathology progression. Brain, behavior, and immunity, 2022. PMID 34343617. doi:10.1016/j.bbi.2021.07.016
Synthesis and evaluation of (99m)Tc-DOTA-ARA-290 as potential SPECT tracer for targeting cardiac ischemic region. Iranian journal of basic medical sciences, 2021. PMID 35317117. doi:10.22038/IJBMS.2021.57565.12799
The Non-Erythropoietic EPO Analogue Cibinetide Inhibits Osteoclastogenesis In Vitro and Increases Bone Mineral Density in Mice. International journal of molecular sciences, 2021. PMID 35008482. doi:10.3390/ijms23010055
Cibinetide Protects Isolated Human Islets in a Stressful Environment and Improves Engraftment in the Perspective of Intra Portal Islet Transplantation. Cell transplantation, 2021. PMID 34498509. doi:10.1177/09636897211039739
An engineered non-erythropoietic erythropoietin-derived peptide, ARA290, attenuates doxorubicin induced genotoxicity and oxidative stress. Toxicology in vitro : an international journal published in association with BIBRA, 2020. PMID 32335150. doi:10.1016/j.tiv.2020.104864
Improvement of Islet Allograft Function Using Cibinetide, an Innate Repair Receptor Ligand. Transplantation, 2020. PMID 32345869. doi:10.1097/TP.0000000000003284
A Phase 2 Clinical Trial on the Use of Cibinetide for the Treatment of Diabetic Macular Edema. Journal of clinical medicine, 2020. PMID 32674280. doi:10.3390/jcm9072225

Questions

Yes. ARA-290 is the original development code and cibinetide is the international nonproprietary name assigned to the same 11-amino-acid erythropoietin-derived peptide. The unhyphenated form "ARA290" also refers to the same molecule. Literature searches should include all three terms, since papers use them interchangeably depending on publication date and journal convention, and restricting to one term will miss relevant work.

ARA-290 corresponds to a solvent-exposed region of the erythropoietin helix B that does not participate in binding the classical homodimeric EPO receptor responsible for red blood cell production. Because the peptide reproduces only that surface, it is reported not to stimulate erythropoiesis while retaining affinity for the receptor complex associated with tissue protection. This separation was the explicit design goal behind the molecule.

The innate repair receptor is described in the literature as a heteromeric complex formed by the erythropoietin receptor and the beta-common receptor, CD131. It is characterized as being upregulated on tissues under metabolic or inflammatory stress rather than constitutively abundant. This conditional expression is the basis for the hypothesis that ARA-290 signaling is largely restricted to injured tissue, though direct structural characterization of the complex remains incomplete.

No. ARA-290 (cibinetide) is not FDA-approved for the treatment or management of any condition discussed here. It has been evaluated in early-stage clinical investigation, including a published Phase 2 trial in diabetic macular edema, but investigational status is not approval. Material supplied for laboratory work is designated research use only and is not intended for human or veterinary administration.

Published work spans small-fiber neuropathy in early exploratory clinical studies, pancreatic islet protection and transplantation models, chemotherapy-associated kidney and genomic stress in rodent and in vitro systems, neuroinflammation in an Alzheimer's-like rodent model, osteoclastogenesis and bone mineral density in mice, and a radiolabeled conjugate evaluated as a cardiac ischemia imaging tracer. Most of this evidence remains preclinical and preliminary.

A useful certificate of analysis is batch-specific, tied to the exact lot number on the vial, and ideally produced by an independent laboratory. It should include an HPLC chromatogram rather than a bare purity figure, so peak shape and impurity peaks are visible, plus mass spectrometry confirming that the observed mass matches the expected mass for the eleven-residue sequence. Lot traceability ties documentation to physical material.

RESEARCH USE ONLY · NOT EVALUATED BY THE FDA