The COSMOS Registry of CytoSorb Hemoadsorption Therapy in Critically Ill Patients: Protocol for an International, Prospective Registry.

Background: Extracorporeal blood purification with CytoSorb has been increasingly used as an adjunctive therapy in several hyperinflammatory critical care conditions, as well as to remove elevated levels of myoglobin or bilirubin in patients with rhabdomyolysis or liver failure. Despite the increasing worldwide use of hemoadsorption, data from large international multicenter studies are still lacking.

Objective: The COSMOS (CytoSorb Treatment Of Critically Ill Patients) registry is a company-sponsored registry by CytoSorbents Corporation and CytoSorbents Medical Inc. and will provide a data repository and reporting infrastructure for the surveillance of CytoSorb use in real-world critical care settings in an unselected, critically ill patient population. The gathered data will serve as a comprehensive resource to assess the effects of such therapy on patients' management.

Methods: The international COSMOS registry is collecting prospective data for patients treated with CytoSorb during routine care in various critical care indications, based on the decision of the treating physicians. Data are collected at baseline, during CytoSorb therapy, 24 hours thereafter, at discharge from the intensive care unit and the hospital, and on day 90. Key outcomes assessed include change in inflammatory biomarkers, vasopressor requirements, fluid balance, organ function and organ support, length of intensive care unit and hospital stay, occurrence of adverse events, and mortality.

Results: The COSMOS registry started with the inclusion of the first patient on July 15, 2022, and is now actively enrolling in 4 countries (Germany, Spain, Portugal, and Italy), with plans to expand to other countries outside of Europe. An initial readout is planned for presentation at an international Critical Care conference in 2024.

Conclusions: The COSMOS registry is intended to provide comprehensive real-world data on patient outcomes with CytoSorb in various critical care indications, thereby contributing to optimization of patient selection, timing of initiation, and dosing of hemoadsorption treatment.

Trial registration: ClinicalTrials.gov NCT05146336; https://clinicaltrials.gov/study/NCT05146336.

International registered report identifier (irrid): DERR1-10.2196/55880.