Low‐density lipoprotein apheresis is associated with removal of SARS‐CoV‐2 antibodies

BACKGROUND: Low-density lipoprotein apheresis is not specific to lipoproteins but removes immunoglobulins as well. It remains elusive, whether protective SARS-CoV-2 antibodies after vaccination from COVID-19 are eliminated as well. METHODS: A cross-sectional case-control study on 55 patients undergoing weekly lipoprotein apheresis and 21 patients with comparable comorbidities and epidemiology not undergoing apheresis. SARS-CoV-2 IgG was assessed in all patients prior to apheresis and in 38 patients both before and after apheresis. RESULTS: SARS-CoV-2 IgG concentrations before a session of lipoprotein apheresis were comparable to control patients not undergoing apheresis(1727 IU/ml, IQR 365-2500) vs. 1652 IU/ml,(IQR408.8-2500), p = 0.78). SARS-CoV-2 IgG concentrations were reduced by lipoprotein apheresis from 1656 IU/ml(IQR 540.5-2500) prior to 1305 IU/ml (IQR 449-2500) afterwards(p < 0.0001). CONCLUSION: Lipoprotein apheresis removes SARS-CoV-2 IgG. The average elimination rate was 21.2%. In the present population of patients undergoing apheresis once weekly, however, the elimination did not lead to inferior concentrations compared to patients not undergoing lipoprotein apheresis.