Ara-290 10mg

Full-length EPO at doses required for tissue protection stimulates the classical EPO receptor (EPOR homodimer) and drives red blood cell production. This hematopoietic stimulation raises hematocrit and increases blood viscosity, which at high EPO doses causes thrombosis and hypertension -- the serious adverse effects seen with high-dose EPO misuse. By engineering a peptide that selectively activates the tissue-protective receptor pathway (EPOR/beta common receptor heterodimer, the innate repair receptor) without engaging the erythropoietic homodimer, Ara-290 provides the neuroprotective and anti-inflammatory benefits without the cardiovascular risks of EPO-driven polycythemia.

Small fiber neuropathy (SFN) is a condition affecting the unmyelinated C-fibers and thinly myelinated A-delta fibers that carry pain and autonomic signals. It causes burning pain, sensory changes, and autonomic dysfunction. Sarcoidosis-associated SFN is one context where nerve fiber loss can be quantified by corneal confocal microscopy (measuring corneal nerve fiber density). Clinical trials of Ara-290 in sarcoidosis-associated SFN showed increased corneal nerve fiber density (indicating nerve regeneration) and improved neuropathic pain scores compared to placebo -- one of the few demonstrations of pharmacological peripheral nerve regeneration in humans.

The innate repair receptor (EPOR/beta common receptor heterodimer) is expressed in many non-hematopoietic tissues including endothelium, neurons, astrocytes, and immune cells. Its activation promotes cell survival under stress, reduces inflammatory cytokine production, and supports tissue repair. In the context of myocardial ischemia, EPO derivatives protecting through this receptor reduce infarct size in animal models. For inflammation, activation shifts macrophage phenotype toward anti-inflammatory M2-like states. Ara-290's selectivity for this receptor makes it a research tool for dissecting the IRR-mediated versus erythropoietic arms of EPO biology.