ARA-290

Quick Facts

Introduction

ARA-290, also known as cibinetide, is an 11-amino-acid peptide engineered from the helix-B domain of erythropoietin (EPO). Its design addresses a key insight from EPO research: erythropoietin has powerful tissue-protective properties that are mediated by a different receptor from the one responsible for stimulating red-blood-cell production. ARA-290 was created to capture the protective signaling while leaving out the blood-stimulating activity, making it a focused tool for neuroprotection and tissue-repair research.

The conceptual appeal of ARA-290 is that it selectively engages the innate repair receptor (IRR) — a heteromeric complex of the EPO receptor and the beta-common receptor (CD131) — that becomes available on stressed or injured tissue. This places ARA-290 in the broader research conversation about endogenous repair and protection, alongside tissue-repair peptides catalogued in the peptide database such as BPC-157 and TB-500.

This profile covers what ARA-290 is, its EPO-derived structure, the innate-repair-receptor mechanism that defines it, the neuropathy and tissue-protection research it appears in, and how it compares with related compounds. Related entries are catalogued across the research library.

What is ARA-290?

ARA-290 is a short synthetic peptide of 11 amino acids whose sequence corresponds to the helix-B region on the outer surface of the erythropoietin molecule. Research established that this region is responsible for EPO's tissue-protective signaling, which is structurally and functionally separable from the part of EPO that drives red-cell production. ARA-290 isolates that protective epitope as a standalone peptide.

The defining feature of ARA-290 is what it deliberately leaves out: it is non-erythropoietic, meaning it does not stimulate the bone marrow to produce red blood cells. This avoids the increases in blood viscosity and thrombotic risk that limit EPO itself as a tissue-protective agent, and it is the central rationale for studying ARA-290 as a distinct research compound rather than simply using EPO.

Molecular and structural characteristics

Structurally, ARA-290 reproduces a linear stretch of residues from EPO's helix-B face, beginning with a pyroglutamate residue that is a common feature of stabilized N-termini. Because it represents only a small surface segment of the much larger EPO glycoprotein, it lacks the overall fold and the carbohydrate modifications of the parent hormone — and, critically, lacks the region required to engage the homodimeric EPO receptor that drives erythropoiesis.

This selective truncation is the molecular basis for ARA-290's distinct profile: by presenting only the helix-B epitope, it engages the tissue-protective innate repair receptor while being unable to trigger classic erythropoietic signaling. The peptide is water-soluble and modest in size, near 1,257 g/mol, consistent with an 11-residue chain.

Mechanism of action

ARA-290 acts as a selective agonist of the innate repair receptor (IRR), a heteromeric receptor formed by the EPO receptor (EPOR) paired with the beta-common receptor (CD131). Unlike the homodimeric EPOR that mediates red-cell production, this heteromer is upregulated on cells under metabolic stress, injury, or inflammation — so ARA-290 is studied as a signal that preferentially acts where tissue protection is needed.

Engagement of the IRR is associated with anti-inflammatory and anti-apoptotic signaling. In research models this is linked to reduced production of pro-inflammatory mediators, dampened cell-death pathways, and support for tissue recovery. Because the receptor is induced by damage, the protective response is framed as context-dependent rather than constitutive — a recurring theme in the ARA-290 literature.

A major applied focus of this mechanism is the peripheral nervous system, where ARA-290 is studied for its association with relief of neuropathic pain and improvement in markers of small-fiber neuropathy. The tissue-protective signaling is proposed to act on nerve fibers and supporting cells, which is why the compound is investigated in neuropathy research rather than as a blood-cell stimulant.

• Selective agonism of the innate repair receptor (EPOR/CD131 heteromer).
• Anti-inflammatory and anti-apoptotic tissue-protective signaling.
• Receptor upregulated by injury, focusing activity on stressed tissue.
• No stimulation of erythropoiesis, distinguishing it from EPO.

Neuropathy and tissue-protection research

The most prominent applied research context for ARA-290 is neuropathic symptoms. Clinical research has studied it in sarcoidosis-associated small-fiber neuropathy, examining endpoints such as neuropathic symptom scores and corneal nerve fiber density as a measure of small-fiber integrity. It has also been studied in type-2-diabetes research for associations with neuropathic symptoms and metabolic markers.

In preclinical models, the innate-repair-receptor mechanism has been examined across contexts of nerve injury, ischemia, and inflammation, where ARA-290 is associated with reduced tissue damage and improved functional recovery. The unifying interpretation is that activating the protective arm of EPO signaling supports repair while avoiding the hematologic effects of the full hormone.

Research context among repair and protection compounds

ARA-290 occupies a distinctive niche: it is a peptide explicitly engineered to separate the protective from the proliferative actions of a natural hormone. This design logic distinguishes it from broadly studied tissue-repair peptides such as BPC-157 and TB-500, which are investigated for healing and recovery through different, more general mechanisms.

Its primary framing as a neuroprotective compound also links it to the broader nervous-system research conversation that includes neuroactive preparations like Cerebrolysin, though ARA-290's receptor-defined mechanism is far more specific. The full set of related compounds is catalogued in the peptide database and research library.

Comparison: ARA-290 vs Erythropoietin vs BPC-157

ARA-290 is most informatively compared with its parent hormone erythropoietin (EPO) and with the general tissue-repair peptide BPC-157. The key contrasts are receptor selectivity and the presence or absence of blood-stimulating activity.

Researchers frame ARA-290 as capturing EPO's protective signaling without its hematologic effects, a contrast central to why it is studied as a separate compound. Full entries are in the peptide database.

Half-life and pharmacokinetic considerations

As a small linear peptide, ARA-290 is expected to have a short circulating half-life, since peptides of this size are rapidly cleared and degraded by peptidases. This is a general property of the class, and detailed human pharmacokinetic parameters are characterized mainly within its clinical research programs rather than being broadly established.

A notable interpretive point is that the innate repair receptor is induced by tissue stress, so the relevant pharmacology concerns not only circulating peptide levels but also where and when the receptor is available. Researchers therefore consider the timing of exposure relative to injury, and pharmacokinetic figures should be read as approximate and study-specific.

Reconstitution and handling considerations

ARA-290 is supplied as a lyophilized powder and reconstituted with sterile or bacteriostatic water, added slowly down the vial wall and swirled gently rather than shaken to protect the peptide. The reconstituted solution should be clear; cloudiness or particulates indicate it should be discarded.

Working concentration is chosen so research volumes are convenient and reproducible. The reconstitution calculator and reconstitution guide describe the standard aqueous method used across peptide research.

• Add diluent slowly; swirl gently rather than shaking.
• Confirm the solution is clear before use.
• Label vials with concentration and reconstitution date.
• Protect from light and excess warmth.

Storage considerations

Lyophilized ARA-290 is most stable frozen at −20 °C, kept dry and away from light. Once reconstituted, it is refrigerated at 2–8 °C and used within a limited window; aliquoting reduces how often a given solution is freeze–thaw cycled, which helps preserve a small peptide's integrity.

Research limitations

ARA-290 is an investigational peptide whose clinical research base, while mechanistically well-motivated, remains relatively early-stage and modest in size for the specific neuropathy populations studied. The innate-repair-receptor concept is still being characterized, and longer-term and larger studies are needed to clarify the durability and generalizability of reported effects. It is described here strictly for research reference.

• Clinical studies are relatively early-stage and modest in size.
• The innate-repair-receptor mechanism is still being characterized.
• Reported effects are population-, dose-, and design-dependent.
• It is not an approved therapy and is described solely for research reference.

Frequently Asked Questions

Related Research Profiles

References

1. Brines M, Patel NSA, Villa P, et al. Nonerythropoietic, tissue-protective peptides derived from the tertiary structure of erythropoietin. Proceedings of the National Academy of Sciences. 2008.
2. 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. Molecular Medicine. 2013.
3. 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. Molecular Medicine. 2015.