Background: The COVID-19 pandemic has serious impact on health and economics worldwide. Despite the recent advent of SARS-Cov-2 vaccines, treatment options are needed, yet pharmacologic interventions remain limited. Several extracorporeal treatments are currently explored concerning their potential to improve the clinical course and outcome of critically ill patients with COVID-19. The Seraph® 100 Microbind® Affinity adsorber (Exthera Medical, CA, USA) has recently been introduced for the elimination of several pathogens from the blood and an emergency
authorization in patients with COVID-19 was granted by the FDA. Bacteria, viruses (including the SARS-CoV-2 spike glycoprotein), fungi and toxins have been shown to bind to the immobilized heparin on the ultra-high molecular weight polyethylene beads of the device in a similar way to the interaction with heparan sulfate on the cellsurface and are thereby removed from the bloodstream. Here we report the interim analysis of the COVID-19 patients treated with the Seraph® 100 Microbind® Affinity filter (COSA) registry. The goal of the registry is to gather data regarding the safety and efficacy of the Seraph® 100 in the treatment of COVID-19 patients.