ARA-290 (Cibinetide): An EPO-Derived Peptide for Tissue Protection and Neuropathy Research

This content is provided by Superpower Health for educational and informational purposes only. Superpower Health does not prescribe, sell, or facilitate access to ARA-290 (cibinetide). ARA-290 is not FDA-approved for human use. This page is not a substitute for medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider.

Erythropoietin is best known as the hormone that tells your bone marrow to produce red blood cells — the same mechanism that made it a target for doping in endurance sports. What took researchers longer to recognize is that EPO does something else entirely through a second receptor complex, one that has nothing to do with blood production. In preclinical models and early clinical trials, activating that second receptor has been studied for its effects on nerve repair, pain signaling, and tissue protection. ARA-290 was engineered specifically to hit that second receptor while leaving the erythropoietic pathway alone.

This article covers what ARA-290 is, how the innate repair receptor mechanism works, what Phase II clinical trials in sarcoidosis-associated small-fiber neuropathy and type 2 diabetes found, and where development of this compound currently stands.

Key Takeaways

• Regulatory Status: Not FDA-approved for human use; received orphan drug designation for sarcoidosis-associated small-fiber neuropathy but was never submitted for full approval. As of April 2026, Araim Pharmaceuticals, the company that developed ARA-290, has closed operations, and no active IND or NDA exists.
• Research Stage: Phase II human trials completed in sarcoidosis-associated small-fiber neuropathy and type 2 diabetes; no Phase III trials initiated; development stalled following Araim Pharmaceuticals shutdown.
• Availability: Not legally marketed for human use; Superpower does not offer this substance.
• What it is: An 11-amino-acid synthetic peptide derived from the helix-B surface of erythropoietin, studied for tissue protection and neuropathic pain via the innate repair receptor.
• What the evidence actually shows: Phase II RCTs showed improvements in neuropathic pain scores and corneal nerve fiber density in sarcoidosis patients; no Phase III data exists as of April 2026.
• Prescribing information: View compound reference data (PubChem CID 16132310)

Where ARA-290 Comes From and How It Works

Origin and discovery

ARA-290 emerged from a body of work by Michael Brines and Anthony Cerami focused on EPO's non-hematopoietic effects. The central insight, described by Leist and colleagues in a 2004 paper in Science, was that chemically modifying EPO to eliminate its erythropoietic activity did not eliminate its tissue-protective properties — suggesting the two functions operate through distinct receptor systems. That separation of function created a research target: a molecule that could engage the tissue-protective arm of the EPO signaling system without raising hematocrit. ARA-290 was the result. In a 2008 paper in Proceedings of the National Academy of Sciences, Brines and colleagues described engineering the compound from the helix-B surface of the EPO molecule, identifying an 11-amino-acid sequence that selectively activates the tissue-protective receptor without binding the classical homodimeric EPOR.

The innate repair receptor: proposed mechanism

The key to understanding ARA-290 is the distinction between EPO's two receptor systems. The classical erythropoietic pathway runs through a homodimeric EPO receptor (EPOR-EPOR), which drives red blood cell production in the bone marrow. The tissue-protective pathway operates through a heterodimeric complex composed of EPOR and the beta-common receptor (also called CD131 or βcR) — a configuration Brines and Cerami named the innate repair receptor (IRR). In a landmark 2004 study in PNAS, Brines and colleagues demonstrated that this EPOR/βcR heteroreceptor mediates EPO's neuroprotective and cytoprotective effects and is pharmacologically separable from the erythropoietic receptor. ARA-290 was designed to bind the IRR selectively. A 2012 mechanistic review in Molecular Medicine by Brines and Cerami framed the IRR as a receptor that modulates innate immune response and promotes cellular survival signals under conditions of injury or metabolic stress. The proposed downstream effects include activation of survival kinase pathways (Akt, ERK), suppression of inflammatory cytokine release, and attenuation of microglial and macrophage activation in neural tissue.

Non-erythropoietic selectivity

The defining feature of ARA-290 is what it does not do. Because it engages the IRR heterodimer rather than the homodimeric EPOR, it does not stimulate erythropoiesis or raise red blood cell counts. This was established in early animal studies and confirmed in human trials where hematological parameters remained stable during administration. A 2014 review in Molecular Medicine by Brines positioned the IRR as a "master regulator of injury and healing" whose activation does not carry the cardiovascular and thrombotic risks associated with EPO's erythropoietic effects at supraphysiological doses. A comprehensive 2015 mechanistic review in Pharmacology and Therapeutics by Collino and colleagues catalogued the non-erythropoietic helix-B peptide's tissue-repair effects across organ systems in preclinical models, spanning neural, renal, cardiac, and metabolic contexts.

Pain signaling: peripheral and spinal mechanisms

In rodent pain models, ARA-290 has been studied for effects on both peripheral nociceptors and central pain processing. Swartjes and colleagues, writing in Molecular Pain in 2014, showed that ARA-290 produced long-lasting relief of neuropathic pain in rats with suppression of spinal microglial activation — a finding that supports a neuro-immune mechanism rather than a purely analgesic one. An earlier 2013 PLoS One paper by Swartjes and colleagues provided indirect support for the same pathway, reporting that ketamine's analgesic effect in a nerve-injury model was absent in β-common-receptor (CD131) knockout mice — a finding consistent with IRR signaling being necessary for at least some established analgesic mechanisms. Separately, Zhang and colleagues in a 2016 Peptides paper demonstrated that ARA-290 attenuates pathophysiological pain by targeting the TRPV1 channel, a peripheral nociceptor involved in heat and inflammatory pain signaling. The convergence of central and peripheral mechanisms may explain the breadth of neuropathic pain findings across different experimental models.

What the Human Evidence Looks Like

Phase II trials in sarcoidosis-associated small-fiber neuropathy

The most substantial clinical evidence for ARA-290 comes from a program at Leiden University Medical Center in the Netherlands, where researchers studied the compound in patients with sarcoidosis-associated small-fiber neuropathy (SFN). SFN is a condition in which the small unmyelinated and thinly myelinated nerve fibers of the peripheral nervous system degenerate, producing neuropathic pain, burning sensations, and autonomic symptoms without the large-fiber abnormalities detected on standard nerve conduction studies. Sarcoidosis — a systemic inflammatory condition — is one of several underlying causes. Heij and colleagues reviewed the pathophysiology of sarcoidosis pain and SFN in a 2012 Pain Research and Treatment paper, which outlined why existing symptomatic treatments are generally inadequate and helped establish the rationale for targeting the innate repair receptor as a disease-modifying approach.

The program began with a 2012 randomized double-blind, placebo-controlled pilot trial by Heij and colleagues in Molecular Medicine, which assigned 22 sarcoidosis patients with SFN symptoms (12 ARA-290, 10 placebo) to 2 mg intravenous ARA-290 three times weekly for 4 weeks. The ARA-290 arm showed a Small Fiber Neuropathy Screening List score change of −11.5 ± 3.04 vs. −2.9 ± 3.34 in placebo (p < 0.05), alongside significant improvements in SF-36 pain (Δ −23.4 ± 5.5, p < 0.01) and physical functioning (Δ −14.6 ± 3.9, p < 0.01) subdomains, with no safety concerns raised on clinical or laboratory assessment — a small pilot whose effect-size estimates are inherently imprecise given the 22-patient cohort. A 2014 clinical review by van Velzen and colleagues in Expert Opinion on Investigational Drugs summarized the early ARA-290 program for sarcoidosis SFN, situating the pilot results within the broader development landscape for this rare indication. The pivotal Phase II RCT, published by Dahan and colleagues in Molecular Medicine in 2013, randomized sarcoidosis patients (n = 36) with confirmed SFN in a blinded, placebo-controlled design to 28 days of daily subcutaneous ARA-290 (4 mg) or placebo. The trial reported significant improvements in cold pain threshold (p = 0.027), heat pain threshold (p = 0.032), and thermal sensory limen (p = 0.008), enhanced exercise capacity on the 6-minute walk test, and a significant increase in corneal small-nerve-fiber density by in vivo corneal confocal microscopy — a structural endpoint suggesting nerve regeneration rather than symptomatic relief alone, with benefits sustained at 16-week follow-up. A subsequent Phase 2b 28-day RCT published by Culver and colleagues in Investigative Ophthalmology and Visual Science in 2017 (n = 64) extended this finding: the 4 mg cibinetide arm showed a placebo-corrected mean increase in corneal nerve fiber area of 697 μm²/mm² at day 28 (p = 0.012) and an increase in regenerating intraepidermal GAP-43-positive fibers (p = 0.035). The GAP-43 finding was interpreted as evidence of active nerve fiber regeneration — a disease-modifying signal rather than a purely symptomatic one.

A 2018 cross-cohort analysis by Brines and colleagues in Scientific Reports further characterized the use of corneal nerve fiber size as a diagnostic and therapeutic response marker in SFN, supporting the validity of the structural endpoints used in the cibinetide trials. The sarcoidosis SFN program represented meaningful Phase II evidence: two randomized controlled trials with both patient-reported and structural outcome measures showing signals in the same direction.

Phase II data in type 2 diabetes and diabetic neuropathy

A parallel clinical program investigated ARA-290 in patients with type 2 diabetes. A 2015 Phase 2 double-blind, placebo-controlled trial by Brines and colleagues in Molecular Medicine administered 4 mg self-injected subcutaneous ARA-290 or placebo daily for 28 days to patients with type 2 diabetes and reported significant improvements in HbA1c (p = 0.002), PainDetect neuropathic symptom score (p = 0.03), cholesterol-to-HDL ratio (p = 0.039), and triglycerides (p = 0.043), alongside an increase in corneal nerve fiber density in the ARA-290 arm versus no change in placebo, with no potential safety issues identified. These metabolic findings were secondary endpoints and the small, single-program sample size limits generalizability. Separately, a 2020 open-label Phase 2 pilot trial by Lois and colleagues in the Journal of Clinical Medicine administered 4 mg/day subcutaneous cibinetide for 12 weeks to nine patients with diabetic macular edema (eight completed), extending the evidence base beyond peripheral neuropathy into diabetic retinal disease — a condition that shares underlying mechanisms of microvascular inflammation and tissue injury. The very small, uncontrolled cohort limits the strength of any efficacy inference.

Limitations of the existing evidence

Several features of the clinical evidence base limit conclusions. The sarcoidosis SFN trials were conducted at a single institution in the Netherlands, with sample sizes ranging from under 40 to 64 participants. The diabetic neuropathy trial was similarly small and underpowered for the metabolic secondary endpoints. No Phase III multicenter replication study was completed before Araim Pharmaceuticals ceased operations. As of April 2026, no active clinical trials are registered on ClinicalTrials.gov for ARA-290 or cibinetide. The Phase II data provide proof-of-concept signals, particularly the structural nerve regeneration findings, but they do not establish efficacy by the standards required for regulatory approval.

Preclinical Evidence Across Organ Systems

Renal protection

The IRR is expressed in the kidney, and preclinical studies have investigated ARA-290 in models of renal injury. Van Rijt and colleagues published two complementary papers in the Journal of Translational Medicine in 2013 — one showing ARA-290 attenuates renal ischemia/reperfusion injury, and a companion paper describing its renoprotective capacities in the same model. A more recent study by Ghassemi-Barghi and colleagues in Inflammation in 2023 demonstrated ARA-290 protection against cisplatin-induced nephrotoxicity via the EPOR/CD131 complex — a finding relevant to chemotherapy-associated kidney injury. These preclinical renal findings have not yet been studied in human clinical trials.

Cardiac and immune effects

A 2023 paper by Winicki and colleagues in Frontiers in Cardiovascular Medicine reported that a non-hematopoietic EPO-derived peptide reduces cardiac inflammation and prolongs healthspan in animal models. Nairz and colleagues, publishing in Scientific Reports in 2017, showed that cibinetide dampens innate immune cell functions and ameliorates experimental colitis in mice. These findings extend the mechanistic picture: the IRR appears broadly relevant to inflammatory and ischemic injury across organ systems, consistent with the hypothesis that it functions as a general tissue-repair signal.

Cerebral ischemia and autoimmune neurology

In the central nervous system, Wang and colleagues published a 2024 CNS Neuroscience and Therapeutics paper showing ARA-290 mediates brain tissue protection through the beta-common receptor in a cerebral ischemic stroke model. Earlier preclinical work by Liu and colleagues in PLoS One in 2014 demonstrated ARA-290 ameliorates experimental autoimmune neuritis through inflammation suppression and tissue protection, and Chen and colleagues in the Journal of Neuroimmunology in 2014 showed therapeutic effects in experimental autoimmune encephalomyelitis rats. These findings support the mechanistic hypothesis but have not been translated into human trials.

Wound healing and islet protection

Bitto and colleagues, publishing in Biochimica et Biophysica Acta in 2018, demonstrated that cibinetide activation of the EPOR/beta-common receptor complex ameliorates impaired wound healing in genetically diabetic mice. Two separate groups investigated ARA-290 in the context of islet transplantation: Watanabe and colleagues in Transplantation in 2016 showed ARA-290 inhibits macrophage activation and prevents damage to transplanted islets, while Yao and colleagues in Transplantation in 2020 reported cibinetide improves islet allograft function. These findings are consistent with the IRR's proposed role in moderating inflammation at sites of injury or foreign tissue.

Regulatory and Legal Status

FDA classification

As of April 2026, ARA-290 (cibinetide) is not FDA-approved for any human indication. Araim Pharmaceuticals, the company that developed the compound through Phase II, received orphan drug designation from the FDA for sarcoidosis-associated small-fiber neuropathy — a designation that provides certain development incentives but does not constitute approval. No NDA or BLA was filed. Following the closure of Araim Pharmaceuticals, no sponsor holds an active IND for ARA-290 in the United States. The compound has no current regulatory pathway to approval without a new sponsor initiating a development program.

Development status

The stalling of ARA-290's development is attributable to commercial and organizational factors rather than a specific safety signal or regulatory rejection. The Phase II sarcoidosis SFN data was, by the standards of rare disease research, reasonably supportive of proof-of-concept. The scientific rationale for the innate repair receptor as a drug target remains intact. A 2016 review in Pain Reports by Dahan, Brines, Niesters, Cerami, and van Velzen titled "Targeting the innate repair receptor to treat neuropathy" summarized the case for the IRR as a clinically actionable pathway. Whether any organization picks up the development program remains unknown as of April 2026.

What this means practically

ARA-290 is not available through any legal pharmaceutical channel in the United States. It has no FDA-approved formulation, no approved manufacturing pathway, and no licensed prescriber access. Products labeled as ARA-290 or cibinetide sold through online vendors are not regulated by the FDA; their identity, purity, and dosing have not been independently verified. There is no legal pathway for a licensed physician to prescribe ARA-290 in the United States without an active IND.

Safety: What Is and Is Not Known

Clinical safety data from Phase II

The Phase II sarcoidosis trials — the Heij 2012 pilot with 22 participants, the Dahan 2013 RCT with 36 participants, and the Culver 2017 Phase 2b with 64 participants — and the Brines 2015 diabetic neuropathy trial together generated safety data from a combined population of roughly 150 participants, with treatment durations of 4 to 28 days in most protocols. The adverse event profile across these trials was reported as mild, with no serious adverse events attributed to study drug. Consistent with its non-erythropoietic design, hematological parameters were stable across all trials. Additional human exposure data comes from a 2015 neuropsychological study by Cerit and colleagues in European Neuropsychopharmacology, which tested ARA-290 for antidepressant-like properties in healthy volunteers and reported a tolerability profile consistent with the neuropathy trials. However, the sample sizes and durations across all of these studies are insufficient to characterize the full safety profile, particularly for longer-term use or in populations with significant comorbidities. No Phase I first-in-human dose-escalation data has been published in the peer-reviewed literature for the intravenous formulations used in sarcoidosis trials; the safety characterization comes from the Phase II datasets themselves.

Risks from unregulated sources

Any ARA-290 or cibinetide product available for purchase online falls entirely outside the regulatory framework. There is no validated manufacturing process, no stability data, and no independent verification of identity or dosing for these materials. The risks of contamination, incorrect peptide sequence, and incorrect concentration are inherent to unregulated peptide synthesis and cannot be mitigated without pharmaceutical-grade manufacturing oversight.

Who Should Not Use ARA-290

Based on the compound's proposed mechanisms, the following groups face elevated theoretical risk.

• Individuals with active or suspected malignancy: The IRR's proposed effects on cell survival signaling and tissue repair could theoretically support tumor cell survival or proliferation; this has not been formally studied but represents a mechanistic concern.
• Pregnant or breastfeeding individuals: No human safety data exists for these populations. The effects of IRR activation on fetal development or breast tissue have not been studied.
• Individuals with severe renal impairment: While preclinical data suggests renoprotective effects, the pharmacokinetics of ARA-290 in patients with severely reduced renal clearance have not been characterized in clinical trials.
• Competitive athletes: ARA-290 is an EPO-derived peptide with proposed systemic effects. Athletes subject to anti-doping rules should be aware that EPO-related peptides and their analogs are prohibited under the WADA S2 category (Peptide Hormones, Growth Factors, Related Substances and Mimetics). As of the 2026 WADA Prohibited List, non-approved peptides with growth factor or repair activity fall under S0 (Non-Approved Substances). Athletes should consult with their governing body before any investigational compound use.
• Individuals taking anticoagulants or with coagulation disorders: EPO-class compounds have established effects on hematological systems at erythropoietic doses; while ARA-290 is designed to be non-erythropoietic, the absence of data in anticoagulated patients warrants caution.

Which Biomarkers Are Relevant if You Are Exploring Peptide Science?

Understanding your baseline biology is a reasonable starting point regardless of which emerging research compounds you are following. For someone interested in the mechanisms ARA-290 has been studied for — neuropathic pain, tissue protection, and metabolic function — several biomarkers provide objective context.

• High-sensitivity C-reactive protein (hs-CRP): The primary circulating marker of systemic inflammation. ARA-290 has been studied for anti-inflammatory effects via IRR-mediated cytokine suppression; hs-CRP provides a measurable baseline against which inflammatory burden can be tracked.
• Hemoglobin A1c (HbA1c): The standard marker of glycemic control over the prior 2-3 months. One of the Phase II diabetic neuropathy trials reported secondary HbA1c improvements; this marker is directly relevant to the metabolic context in which diabetic neuropathy develops.
• Estimated Glomerular Filtration Rate (eGFR): The primary clinical marker of kidney filtration function. Preclinical renal protection studies make eGFR a logical baseline marker for anyone researching tissue-protective peptides with renal mechanism data.
• Fasting glucose and fasting insulin: Relevant to the metabolic and neuropathic disease context in which ARA-290 has been studied. Insulin resistance precedes diabetic neuropathy by years; these markers provide early-stage metabolic context.
• Complete blood count (CBC): Confirms baseline hematological status. For any EPO-derived compound, confirming stable hematocrit and red blood cell counts at baseline is standard safety monitoring practice, even for non-erythropoietic variants.
• Comprehensive metabolic panel: Covers liver and kidney function, electrolytes, and metabolic markers. Provides the safety context relevant to any investigational peptide and establishes the organ function baseline that clinical trials use as inclusion criteria.
• Vitamin B12: Deficiency is a common and reversible cause of peripheral neuropathy that overlaps clinically with small-fiber neuropathy. Establishing B12 status rules out a well-characterized treatable contributor before attributing neuropathic symptoms to other causes.

When to Take This Seriously

If you are experiencing neuropathic pain, burning sensations, or loss of sensation in the extremities, those are symptoms with established clinical pathways. A neurologist or primary care physician can evaluate for the underlying causes of peripheral neuropathy — including B12 deficiency, diabetes, autoimmune conditions such as sarcoidosis, and others. The evaluation typically begins with bloodwork: several well-characterized compounds have been studied in the neuropathy context, and understanding whether your symptoms correlate with measurable biomarker abnormalities is the foundation of that evaluation. Understanding your metabolic health baseline — glucose regulation, inflammatory markers, organ function — gives your provider the objective data needed to make those assessments.

ARA-290 is a scientifically interesting case: the innate repair receptor concept offers a plausible mechanistic framework, and the Phase II data from Leiden is more compelling than most research-peptide evidence bases. What it lacks is the Phase III replication and independent multicenter validation required to draw firm conclusions. That gap between a promising mechanism and a proven therapy is exactly where careful biomarker-guided evaluation of your own biology becomes most valuable. That principle — data before decisions — is what drives Superpower's approach to preventive health: understanding your biology is the foundation for every health decision, whether you are exploring established therapies or following emerging research.

IMPORTANT SAFETY INFORMATION

ARA-290 (cibinetide) is NOT FDA-approved for any indication. It is not legally marketed for human use. No NDA or BLA has been submitted. Araim Pharmaceuticals, the clinical-stage sponsor, has closed, and no active IND exists as of April 2026. Superpower Health does not prescribe, sell, compound, or facilitate access to ARA-290. Superpower connects members with licensed providers and a comprehensive biomarker testing platform; Superpower does not prescribe or dispense medications, and does not offer investigational compounds.

Clinical safety data is limited to Phase II trials with combined enrollment under 200 participants and short treatment durations. Longer-term safety has not been characterized. Hematological parameters were stable in reported trials, consistent with the compound's non-erythropoietic design.

Theoretical safety considerations based on proposed mechanism: potential effects on cell survival signaling in individuals with active or suspected malignancy; uncharacterized effects in pregnancy and lactation; uncharacterized pharmacokinetics in severe renal impairment; EPO-derived peptide class falls under WADA prohibited substance categories for competitive athletes.

Products sold online as ARA-290 or cibinetide are unregulated. Their identity, purity, and dosing have not been verified by the FDA or any independent regulatory authority. There is no legal pharmaceutical-grade source for ARA-290 in the United States.

This article is for educational and informational purposes only. It does not constitute medical advice, diagnosis, or treatment guidance. Always consult a qualified healthcare provider before making any health decisions.

Additional Questions

Can a doctor prescribe ARA-290?

No. Without an active FDA-approved indication or an active Investigational New Drug (IND) application, there is no legal pathway for a licensed provider to prescribe ARA-290 in the United States. The compound is not available through compounding pharmacies and has no approved formulation.

Why did ARA-290 development stop?

Araim Pharmaceuticals, the company that sponsored ARA-290's clinical program through Phase II, ceased operations before initiating Phase III trials. The stalling appears to reflect commercial and organizational factors rather than a specific safety finding or regulatory rejection. The scientific rationale for the innate repair receptor target and the Phase II signal in sarcoidosis SFN remain intact in the published literature. As of April 2026, no organization has announced a new development program for this compound.

What is sarcoidosis-associated small-fiber neuropathy?

Sarcoidosis is a systemic inflammatory condition in which clusters of inflammatory cells form in organs throughout the body, most commonly the lungs and lymph nodes. A subset of sarcoidosis patients develop small-fiber neuropathy: degeneration of the small unmyelinated and thinly myelinated nerve fibers of the peripheral nervous system, producing neuropathic pain, burning sensations, and autonomic symptoms. The condition is often missed on standard nerve conduction studies, which test only large-fiber function. It was the lead indication for ARA-290's clinical program because the IRR is expressed in small-fiber nerve tissue and because existing pharmacological options for SFN are limited to symptomatic management.