ARA-290

ARA-290, known by its International Nonproprietary Name cibinetide, is a synthetic peptide of eleven amino acids based on the helix-B domain of the erythropoietin (EPO) molecule. It was developed from the discovery that EPO protects and repairs injured tissue through a receptor distinct from the classic erythropoietin receptor that drives red blood cell production. This tissue-protective receptor, a heteromer of the EPO receptor and the beta-common receptor (CD131), is termed the innate repair receptor (IRR); cibinetide was designed by Anthony Cerami, Michael Brines, and colleagues at Araim Pharmaceuticals to selectively activate the IRR while remaining non-hematopoietic, meaning it does not raise hematocrit or carry the thrombotic risks of EPO ^[3][6].

The peptide antagonizes inflammatory processes and stimulates tissue repair, and its most developed clinical application is small nerve fiber loss and neuropathic pain, particularly in sarcoidosis. In randomized placebo-controlled trials, daily subcutaneous cibinetide over 28 days improved neuropathic symptoms, increased corneal small-nerve-fiber density measured by corneal confocal microscopy, and improved exercise capacity ^[1][2]. Preclinically, cibinetide has shown benefit across a range of inflammatory and repair models, including experimental colitis, diabetic wound healing, and ischemic retinopathy ^[4][5][6].

ARA-290 is an investigational agent and has not received marketing approval for any indication; it has been evaluated in phase 2 trials for sarcoid neuropathy and studied in diabetes and other conditions. It is administered as a subcutaneous injection and has been consistently reported to have an excellent safety profile in trials to date ^[3]. It is supplied as a peptide for research and clinical study.

In controlled trials for sarcoidosis-related neuropathy, ARA-290 (cibinetide) was generally well tolerated with a notably clean safety profile. Unlike erythropoietin, it does not stimulate red-blood-cell production, so it avoids EPO's thrombotic risk. It remains investigational, and long-term safety has not been formally established.

ARA-290, also known as cibinetide, grew out of research by Anthony Cerami and Michael Brines showing that the tissue-protective actions of erythropoietin are mediated by a receptor distinct from the one that stimulates red blood cell production. By mapping those protective effects to the helix-B region of the erythropoietin molecule, the team designed an 11-amino-acid peptide that mimics only that surface, giving repair signaling without raising red cell mass. The compound was advanced by Araim Pharmaceuticals of Tarrytown, New York, and moved into phase 2 clinical testing in the 2010s. A notable milestone was a phase 2b randomized trial in sarcoidosis-associated small fiber neuropathy, published in 2017, which used corneal confocal microscopy to show regeneration of small nerve fibers.

ARA-290 is viewed with considerable optimism as a rare example of a peptide that appears to modify disease rather than merely mask symptoms, calming innate immune overactivity while actively regrowing damaged nerves. Researchers are impressed that it captures erythropoietin's regenerative benefits while deliberately avoiding the clotting and blood-thickening risks tied to erythropoiesis, and controlled trials have documented both reduced neuropathic pain and measurable increases in corneal and skin nerve fibers. Its consistently clean safety profile in studies is frequently cited as a strength. In fairness, it remains an investigational agent without regulatory approval, and the pivotal trials have been relatively small. Even so, its combination of anti-inflammatory and pro-regenerative action keeps it a compound of genuine scientific interest, particularly for small fiber neuropathy.