ARA-290

What is ARA-290?#

ARA-290, also known as cibinetide, is a synthetic 11-amino acid peptide engineered from the three-dimensional structure of erythropoietin (EPO). Developed by Araim Pharmaceuticals, it was designed to retain the tissue-protective and anti-inflammatory properties of EPO while eliminating its erythropoietic (red blood cell-stimulating) activity. This selective activity profile makes ARA-290 suitable for therapeutic applications where tissue protection is desired without the cardiovascular risks associated with EPO-induced increases in hematocrit.

The peptide was developed based on the discovery by Michael Brines and Anthony Cerami that EPO signals through two distinct receptor systems: the classical EPO receptor homodimer (responsible for erythropoiesis) and the innate repair receptor (IRR), a heteromer of the EPO receptor and the beta common receptor (CD131), which mediates tissue protection and repair.

Mechanism of Action#

ARA-290 selectively activates the innate repair receptor (IRR), a heteromeric complex composed of the erythropoietin receptor (EPOR) and the beta common receptor (CD131/betacR). This receptor complex is expressed on multiple cell types including neurons, Schwann cells, endothelial cells, and immune cells, particularly at sites of tissue injury and inflammation.

Innate Repair Receptor Signaling#

Upon binding to the IRR, ARA-290 activates downstream signaling pathways including JAK2-STAT5, PI3K-Akt, and NF-kB modulation. These pathways collectively mediate anti-inflammatory effects, anti-apoptotic signaling, promotion of nerve fiber regeneration, and modulation of immune cell activity. Despite a short plasma half-life (minutes), ARA-290 triggers sustained biological effects when concentrations exceed the low nanomolar receptor affinity threshold.

Anti-Inflammatory Effects#

ARA-290 shifts macrophage polarization from pro-inflammatory (M1) to anti-inflammatory and tissue-repair (M2) phenotypes. This shift reduces the production of pro-inflammatory cytokines (TNF-alpha, IL-1beta, IL-6) while promoting the release of anti-inflammatory mediators and growth factors that support tissue repair.

Nerve Fiber Regeneration#

In both preclinical and clinical studies, ARA-290 has demonstrated the ability to promote small nerve fiber regeneration. This is measured clinically through corneal confocal microscopy (corneal nerve fiber density) and skin biopsy (intraepidermal nerve fiber density). The mechanism involves both direct neuroprotective effects on neurons and indirect effects through modulation of the local inflammatory environment.

Research Overview#

ARA-290 has progressed from preclinical studies into multiple Phase 2 clinical trials, making it one of the more clinically advanced neuroprotective peptides in development.

Sarcoidosis-Associated Neuropathy#

A 2012 randomized, double-blind, placebo-controlled pilot study in 22 sarcoidosis patients with small fiber neuropathy (SFN) showed that ARA-290 (2 mg IV, three times weekly for 4 weeks) significantly improved SFN screening scores compared to placebo, with no safety concerns identified. A follow-up 2013 study demonstrated that 28 days of daily subcutaneous ARA-290 improved neuropathic symptoms and increased corneal nerve fiber density in sarcoidosis patients.

Diabetic Neuropathy#

A clinical study in patients with type 2 diabetes showed that daily subcutaneous ARA-290 (4 mg) for 28 days improved hemoglobin A1c, lipid profiles, neuropathic symptoms, and corneal nerve fiber density. The improvements persisted through a 28-day post-treatment observation period.

Regulatory Status#

ARA-290 has received FDA Orphan Drug designation for the treatment of sarcoidosis, recognizing the unmet medical need in this patient population.

Important Considerations#

ARA-290 is an investigational compound that has not yet received regulatory approval for any indication. While clinical trial data are encouraging, the compound is still in Phase 2 development, and larger Phase 3 trials would be needed to confirm efficacy and establish a comprehensive safety profile. The compound's short plasma half-life has implications for dosing frequency and route of administration.

Key Research Findings#

Safety and efficacy of ARA 290 in sarcoidosis patients with symptoms of small fiber neuropathy: a randomized, double-blind pilot study, published in Molecular Medicine (Heij L et al., 2012; PMID: 23168581):

First randomized, double-blind, placebo-controlled trial of ARA-290 in sarcoidosis patients with small fiber neuropathy, showing significant improvement in neuropathic symptoms with no safety concerns.

• Significant improvement in SFN screening score at week 4 vs placebo
• No safety concerns identified
• ARA-290 2 mg IV three times weekly for 4 weeks was well tolerated

ARA 290 improves symptoms in patients with sarcoidosis-associated small nerve fiber loss and increases corneal nerve fiber density, published in Molecular Medicine (Dahan A et al., 2013; PMID: 24136731):

Follow-up study demonstrating that 28 days of daily subcutaneous ARA-290 improved neuropathic symptoms and increased corneal nerve fiber density in sarcoidosis patients with documented small nerve fiber loss.

• Improved neuropathic symptom scores
• Increased corneal nerve fiber density (objective measure of nerve regeneration)
• Effects observed in patients with documented small nerve fiber loss

ARA 290, a nonerythropoietic peptide engineered from erythropoietin, improves metabolic control and neuropathic symptoms in patients with type 2 diabetes, published in Molecular Medicine (Brines M et al., 2015; PMID: 25387363):

Clinical study showing that daily subcutaneous ARA-290 for 28 days improved hemoglobin A1c, lipid profiles, and neuropathic symptoms in patients with type 2 diabetes, with increased corneal nerve fiber density.

• Improvement in hemoglobin A1c
• Improved lipid profiles
• Significant improvement in neuropathic symptoms

Related Reading#

• ARA-290 research studies and evidence
• ARA-290 dosing protocols
• ARA-290 side effects profile
• BPC-157 research guide
• Semax research guide