ARA-290 (Cibinetide) is a synthetic 11-amino-acid peptide derived from the helix B region of erythropoietin (EPO). Molecular formula C51H84N16O21, molecular weight 1257.32 g/mol.
The design goal was to strip out EPO’s blood-cell-producing activity while keeping its tissue-protective signalling intact. Full-length EPO acts on a homodimeric receptor on bone marrow cells to drive red blood cell production; ARA-290 does not engage that pathway at all.
Research context
ARA-290 instead activates the innate repair receptor (IRR), a heteromeric complex of the EPO receptor (EPOR) subunit and the beta-common receptor (βcR, CD131). Unlike the classical EPO receptor, the IRR is upregulated selectively at sites of injury or inflammation, which is the basis for describing ARA-290 as a context-restricted repair signal rather than a systemic one. Receptor engagement triggers JAK2 phosphorylation and downstream STAT3/STAT5 and PI3K-Akt signalling, associated with anti-inflammatory and anti-apoptotic effects.
Cibinetide reached orphan-drug designation and Phase 2 clinical trials for sarcoidosis-associated small-fiber neuropathy, with additional trial work in type 2 diabetic neuropathy and neuropathic pain more broadly. Reported trial data show no detectable change in hemoglobin, hematocrit or reticulocyte count after repeated dosing, consistent with the non-erythropoietic design. Preclinical work has additionally examined nerve-fiber regeneration, ischemia-reperfusion injury and corneal wound healing.
ARA-290 is investigational and is not approved for human therapeutic use by the FDA, EMA, MHRA or any other regulator — the clinical trial history is relevant research context, not an indication of approved use.
Specification
CAS number 1208243-50-8 (free base). Supplied as a lyophilized powder, soluble in water. Ships with a batch-specific Certificate of Analysis — cross-check the batch ID printed on your vial against the CoA before use, and see the guide to reading a CoA if you are unfamiliar with the format.
Handling
Reconstitute with bacteriostatic or sterile water, introducing the diluent against the vial wall and swirling gently rather than shaking. Store lyophilized at −20°C protected from light; refrigerate at 2–8°C once reconstituted.
Frequently asked questions about ARA-290
Is ARA-290 the same as EPO?
No — it shares a sequence origin, not a mechanism. ARA-290 is derived from EPO’s helix B region but was engineered to avoid the receptor that drives red blood cell production. Trial data report no change in hemoglobin, hematocrit or reticulocyte count with repeated dosing, which is the practical evidence that the erythropoietic pathway is not being engaged.
What is the innate repair receptor?
A heteromeric receptor complex distinct from the classical EPO receptor, made up of the EPOR subunit paired with the beta-common receptor (CD131). It is selectively upregulated at sites of injury or inflammation rather than expressed constitutively like the erythropoietic EPO receptor, which is why ARA-290 is described as acting preferentially where tissue repair signalling is already active.
What has ARA-290 been studied for clinically?
Sarcoidosis-associated small-fiber neuropathy is the primary orphan-drug indication, with Phase 2 trial work also covering type 2 diabetic neuropathy and neuropathic pain syndromes generally. It remains investigational and is not approved for therapeutic use by any major regulator.
How is ARA-290 stored and handled?
Bacteriostatic or sterile water for reconstitution. Introduce the diluent against the vial wall and swirl gently rather than shaking. Store lyophilized at −20°C protected from light; refrigerate at 2–8°C once reconstituted.
Research use only. Not for human or veterinary use, not for use in diagnostic procedures, and not evaluated by the U.S. Food and Drug Administration.
