Description
Cibinetide (also designated ARA-290) is a synthetic 11-amino-acid peptide belonging to the class of non-hematopoietic erythropoietin analogues. It was engineered to selectively engage the innate repair receptor (IRR), a heteromeric complex formed by the erythropoietin receptor (EPOR) and the β-common receptor (CD131) [2]. Because its sequence diverges from the region of erythropoietin responsible for stimulating red blood cell maturation, cibinetide activates the IRR without substantially engaging the homodimeric EPOR that drives erythropoiesis [2].
The IRR is expressed at relatively low baseline levels in many tissues but becomes upregulated in the presence of injury, ischemia, inflammation, or cellular stress. Upon activation, the receptor complex engages downstream signaling cascades that include JAK2 and suppression of NF-κB subunit p65 activity, resulting in attenuated production of pro-inflammatory cytokines, chemokines, and nitric oxide synthase-2 [2]. These properties make cibinetide a useful molecular tool for researchers investigating the mechanistic boundaries between innate immune activation and tissue-protective signaling.
Investigators have applied cibinetide across a range of preclinical and early translational models. Research groups studying pancreatic islet transplantation have used it to probe how IRR activation modulates the instant blood-mediated inflammatory reaction, graft-infiltrating myeloid cells, and caspase-mediated apoptosis in both murine and isolated human islet systems [1][3]. Separate lines of inquiry have examined its modulatory effects on dendritic cell maturation and allogeneic T-cell responses [1], as well as its capacity to dampen myeloid cell activity in inflammatory bowel models [2]. Early-phase clinical investigation has also explored cibinetide in the context of ocular conditions associated with inflammation and vascular leakage [4].
References
[1] Improvement of Islet Allograft Function Using Cibinetide, an Innate Repair Receptor Ligand. Transplantation, 2020. https://pubmed.ncbi.nlm.nih.gov/32345869/
[2] Cibinetide dampens innate immune cell functions thus ameliorating the course of experimental colitis. Scientific Reports, 2017. https://pubmed.ncbi.nlm.nih.gov/29026145/
[3] Cibinetide Protects Isolated Human Islets in a Stressful Environment and Improves Engraftment in the Perspective of Intra Portal Islet Transplantation. Cell Transplantation, 2021. https://pubmed.ncbi.nlm.nih.gov/34498509/
[4] A Phase 2 Clinical Trial on the Use of Cibinetide for the Treatment of Diabetic Macular Edema. Journal of Clinical Medicine, 2020. https://pubmed.ncbi.nlm.nih.gov/32674280/
