A Report on the First 7 Sequential Patients Treated Within the C-Reactive Protein Apheresis in COVID (CACOV) Registry

BACKGROUND Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced pneumonia is a disease with high mortality and, still, no effective treatment. Excessively elevated C-reactive protein (CRP) plasma levels inversely correlate with prognosis. As CRP, via complement and macrophage activation, can cause organ damage in COVID-19, we have recently introduced selective CRP apheresis as a potentially effective treatment. Now, we report on the first patients with severe SARS-CoV-2-induced pneumonia treated within the "C-reactive protein Apheresis in COVID" (CACOV) registry. CASE REPORT Seven sequential hospitalized patients with documented COVID-19, strongly elevated CRP plasma levels, and respiratory failure were treated by selective CRP apheresis in addition to standard therapy after having given their informed consent for inclusion in the CACOV registry. We performed 2-8 CRP apheresis sessions via either peripheral or central venous access depending on clinical course and CRP plasma levels. CRP apheresis, in COVID-19, reduced CRP plasma levels by approximately 50-90%, and it was thus highly effective, feasible, and safe. Despite severe radiological lung involvement in all our patients, only 2 patients finally required intubation, and none required extracorporeal membrane oxygenation (ECMO). All 7 patients were discharged from our 2 hospitals in good clinical condition. CONCLUSIONS Selective CRP apheresis, starting early after patient admission, may be an effective treatment of SARS-CoV-2-induced pneumonia. SARS-COV-2 can cause organ damage and multiple organ failure predominantly by an excessive CRP-mediated autoimmune response of the ancient innate immune system. Further registry data and randomized trials are needed.