Antibody Binding and Neutralization of Live SARS-CoV-2 Variants Including BA.4/5 Following Booster Vaccination of Patients with B-cell Malignancies

Patients with non-Hodgkin lymphoma and chronic lymphocytic leukemia (NHL/CLL) elicit inadequate antibody responses after initial SARS-CoV-2 vaccination and remain at high risk of severe COVID-19 disease. We investigated IgG, IgA, and IgM responses after booster vaccination against recent SARS-CoV-2 variants including Omicron BA.5 in 67 patients. Patients had lower fold increase and total anti-spike binding titers after booster than healthy individuals. Antibody responses negatively correlated with recent anti-CD20 therapy and low B-cell numbers. Antibodies generated after booster demonstrated similar binding properties against SARS-CoV2 variants compared with those generated by healthy controls with lower binding against Omicron variants. Importantly, 43% of patients showed anti-Omicron BA.1 neutralizing antibodies after booster and all these patients also had anti-Omicron BA.5 neutralizing antibodies. Patients with NHL/CLL demonstrated inferior antibody responses after booster vaccina-tion, particularly against Omicron variants. Prioritization of prophylactic and treatment agents and vaccination of patients and close contacts with updated vaccine formulations are essential. Significance: Limited data exist on antibody responses against current SARS-CoV-2 variants after booster vaccination in patients with NHL/CLL. We showed inferior antibody responses against Omicron variants after booster vaccination in these patients but some generated anti-Omicron titers. This stresses the importance of vaccinating patients with updated formulations.