ARA-290 — international nonproprietary name cibinetide — is a synthetic 11-amino-acid peptide engineered from the helix B surface domain of erythropoietin (EPO) [ref-1]. EPO is best known as the hormone that drives red-blood-cell production, but a separate, tissue-protective signalling axis had been described for the same molecule. ARA-290 was designed to isolate that second activity: it retains cytoprotective and anti-inflammatory effects while removing the erythropoietic drive that makes recombinant EPO unsuitable for repeated use outside anaemia.

Peptide Data grades the evidence base Moderate. That grade reflects genuine Phase II human data in two indications — it does not mean established efficacy. No Phase III trial has been completed, and the compound is not approved as a medicine in any jurisdiction.

This article describes published research and trial methodology only. It is not medical advice, and nothing here should be read as guidance for human use.

01 — What ARA-290 is

  • ARA-290 is a synthetic peptide of 11 amino acids, first described in the tissue-protective EPO literature in 2008 [ref-1].
  • It is studied as a research compound. It is not a licensed medicine and is not a controlled substance in the UK.
  • Its reported half-life after subcutaneous administration in clinical-trial conditions is short — on the order of one to two hours — which is why the trials below used daily or three-times-weekly dosing.

02 — Mechanism: the innate repair receptor

  • ARA-290 is an agonist at the innate repair receptor (IRR), a heteromeric complex formed by the EPO receptor and CD131 (the beta-common receptor) [ref-1][ref-7].
  • IRR activation is reported to engage anti-apoptotic (JAK2/STAT3) and tissue-repair (PI3K/Akt) signalling. Because ARA-290 does not engage the classical erythropoietin-receptor homodimer, it does not raise haematocrit — a property observed across the clinical trials described below.
  • Preclinical work reports tissue-protective effects in animal models of cardiac ischaemia, stroke and kidney injury [ref-1]. These are animal-model findings and do not establish human benefit.
  • Separate preclinical work has reported that ARA-290 interacts with the TRPV1 channel [ref-10], offered as one possible route to its analgesic-like effects in pain models. This remains a mechanistic hypothesis rather than an established mechanism in humans.

03 — The clinical record

All of the human data below come from small, early-phase trials run under clinical-trial conditions. Doses are given to describe trial protocols, not as any recommendation.

Sarcoidosis-associated small fibre neuropathy

  • Pilot trial (Heij et al., 2012; n = 22). A randomised, double-blind, placebo-controlled single-centre study in the Netherlands gave intravenous ARA-290 2 mg three times weekly for four weeks, with three-month follow-up. The ARA-290 arm showed a change in the Small Fibre Neuropathy Screening List (SFNSL) of −11.5 ± 3.04 versus −2.9 ± 3.34 for placebo (p < 0.05), alongside improvements in SF-36 pain and physical-functioning subdomains [ref-2][ref-6]. The cohort is small and the effect-size estimates correspondingly imprecise.
  • Phase 2b trial (NCT02039687; Culver et al., 2017). Sixty-four patients with sarcoidosis and painful neuropathy received daily subcutaneous cibinetide at 1, 4 or 8 mg, or placebo, for 28 days. The primary endpoint addressed small nerve-fibre loss and repair. The sponsor reported a 23% increase in corneal nerve-fibre abundance at the 4 mg dose versus placebo, a clinically meaningful reduction in pain intensity among patients with moderate-to-severe baseline pain, and no safety issues [ref-3][ref-8].
  • NERVARA. A further randomised, placebo-controlled Phase II (reported as n = 38 in the review literature) used subcutaneous ARA-290 4 mg daily for four weeks with three-month follow-up, focusing on small-fibre morphology and the six-minute walk test. Corneal nerve-fibre area rose about 14% over the treatment period against a small decrease on placebo, and 50% of ARA-290-treated patients walked at least 25 m further, versus 12% on placebo [ref-6].

One honest caveat: published and sponsor accounts describe the sarcoidosis programme with differing sample sizes (22, 38 and 64 across the pilot, NERVARA and the Phase 2b respectively). The exact enrolment of each analysis should be treated as unsettled until checked against the primary papers.

Diabetic neuropathy

  • A randomised, double-blind, placebo-controlled investigator-initiated trial (Netherlands Trial Register NTR3858) gave 48 patients with type 2 diabetes and moderate-to-severe small-fibre-neuropathy pain daily subcutaneous ARA-290 4 mg, or placebo, for 28 days, with follow-up to day 56 [ref-4].
  • Reported outcomes included improvements in neuropathic symptom questionnaires (SFNSL, PainDetect, NPSI) and quality of life (RAND-36), an increase in corneal nerve-fibre density in patients who had a baseline reduction, and improvements in HbA1c and lipid profile that persisted into the 56-day follow-up [ref-4][ref-6].
  • The trial was powered for symptom endpoints, not for the metabolic secondary endpoints, so the glycaemic and lipid findings should be treated as exploratory [ref-6].

Other programmes

A small Phase II study of cibinetide in diabetic macular oedema was also conducted and published in 2020 [ref-9]. It does not change the overall picture: the compound's human evidence base remains a set of small early-phase studies.

04 — Where the evidence stops

  • No Phase III. No multicentre confirmatory trial was completed before the developer, Araim Pharmaceuticals, ceased operations. As of 2026 there are no active registered trials of ARA-290 or cibinetide.
  • Small, concentrated cohorts. The sarcoidosis work was conducted largely at a single institution in the Netherlands, with sample sizes under 40 to 64 participants. The diabetic-neuropathy trial was similarly small.
  • No long-term safety or durability data. The longest follow-up in the published programme is measured in months, not years.
  • Designations are not approvals. Cibinetide received US and EU Orphan Drug designations for sarcoidosis, and a US Fast Track designation for neuropathic pain in sarcoidosis, with an end-of-Phase-2 meeting with the US regulator reported in 2017 [ref-8]. These are development incentives in other jurisdictions; they are not marketing authorisations, and they have no bearing on UK licensing.

For these reasons the Moderate grade reflects Phase II proof-of-concept signals — including a structural nerve-regeneration signal that is unusual in this field — rather than demonstrated clinical benefit.

05 — UK legal status

  • ARA-290 is not a licensed medicine in the UK and holds no MHRA marketing authorisation.
  • It is not a controlled drug under the Misuse of Drugs Act 1971.
  • Any human use in the UK would require a clinical trial authorisation from the MHRA together with research-ethics approval, under the Medicines for Human Use (Clinical Trials) Regulations 2004 as amended by the 2026 clinical-trials reforms. One of the cibinetide studies in this programme — the diabetic macular oedema trial — was run at a UK centre, which is the route by which such a compound can lawfully be given to participants here.
  • Supply of the material for laboratory research sits outside the medicines-licensing regime; supply for human use is governed by the Human Medicines Regulations 2012 and MHRA enforcement. ARA-290 is a research-use-only compound: it is not for human consumption, and nothing in this article is dosing or self-administration guidance.

06 — Bottom line

ARA-290 is a mechanistically interesting, non-erythropoietic EPO derivative with two small Phase II programmes that produced encouraging symptom and nerve-fibre signals in difficult-to-treat neuropathies. It is not a licensed medicine, it has no Phase III evidence, and its clinical development has stalled. Until confirmatory data exist, the appropriate reading is that ARA-290 is a compound of research interest — not an established therapy, and not something the published record supports using outside a trial.

This article is AI-researched and editorially reviewed. It is provided for research and educational purposes only and is not medical advice. Research peptides are not licensed for human consumption in the UK.