Interim analysis of the COSA (COVID-19 patients treated with the Seraph(R) 100 Microbind(R) Affinity filter) registry

Schmidt JJ, Borchina DN, Van'T Klooster M, Bulhan-Soki K, Okioma R, Herbst L, Rodriguez DS, Premuzic V, Buettner S, Bader B, Serednicki W, Zasada E, Schmitz M, Quabach RA, Hrincheva M, Fuehner T, Kielstein JT (2021)

Publication Type: Journal article

Publication year: 2021


DOI: 10.1093/ndt/gfab347


Background The Seraph(R) 100 Microbind(R) Affinity Blood Filter is a haemoperfusion device that is licensed for the reduction of pathogens, including several viruses, in the blood. It received Emergency Use Authorization for the treatment of severe coronavirus disease 2019 (COVID-19) by the Food and Drug Administration (FDA). Several studies have shown that the blood viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) correlates with adverse outcomes and removal of the nucleocapsid of the SARS-CoV-2 virus by the Seraph(R) 100 has been recently demonstrated. The aim of this registry was to evaluate the safety and efficacy of Seraph(R) 100 treatment for COVID-19 patients. Methods Twelve hospitals from six countries representing two continents documented patient and treatment characteristics as well as outcome parameters without reimbursement. Additionally, mortality and safety results of the device were reported. A total of 102 treatment sessions in 82 patients were documented in the registry. Four patients were excluded from mortality analysis due to incomplete outcome data, which were available in the other 78 patients. Results Overall, a 30-day mortality rate of 46.2% in the 78 patients with complete follow-up was reported. The median treatment time was 5.00 h (4.00-13.42) and 43.1% of the treatments were performed as haemoperfusion only. Adverse events of the Seraph(R) 100 treatment were reported in 8.8% of the 102 treatments and represented the premature end of treatment due to circuit failure. Patients who died were treated later in their intensive care unit (ICU) stay and onset of COVID symptoms. They also had higher ferritin levels. Multivariate Cox regression revealed that delayed Seraph(R) 100 treatment after ICU admission (>60 h), as well as bacterial superinfection, were associated with mortality. While average predicted mortality rate according to Sequential Organ Failure Assessment (SOFA) score in ICU patients was 56.7%, the observed mortality was 50.7%. In non-ICU patients, Coronavirus Clinical Characterisation Consortium (4C) score average predicted a mortality rate of 38.0%, while the observed mortality rate was 11.1%. Conclusions The treatment of COVID-19 patients with Seraph(R) 100 is well tolerated and the circuit failure rate was lower than previously reported for kidney replacement therapy (KRT) in COVID-19 patients. Mortality correlated with late initiation of Seraph treatment after ICU admission and bacterial superinfection. Compared with predicted mortality according to 4C and SOFA scores, mortality of Seraph(R) 100-treated patients reported in the registry was lower.

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How to cite


Schmidt, J.J., Borchina, D.N., Van'T Klooster, M., Bulhan-Soki, K., Okioma, R., Herbst, L.,... Kielstein, J.T. (2021). Interim analysis of the COSA (COVID-19 patients treated with the Seraph(R) 100 Microbind(R) Affinity filter) registry. Nephrology Dialysis Transplantation.


Schmidt, Julius J., et al. "Interim analysis of the COSA (COVID-19 patients treated with the Seraph(R) 100 Microbind(R) Affinity filter) registry." Nephrology Dialysis Transplantation (2021).

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