SARS-CoV-2-neutralizing antibody treatment in patients with COVID-19 and immunodeficiency due to B-cell non-Hodgkin lymphoma.

Humoral immunodeficiency is a common finding in patients with B-cell related malignancies such as Non-Hodgkin lymphoma. Failure to induce a sufficient humoral immune response to viral pathogens such as SARS-CoV-2 can result in impaired viral clearance with prolonged viral shedding and symptomatic infections. Here we describe six COVID-19 patients with B-cell Non-Hodgkin lymphoma and impaired humoral immune response that were successfully treated with SARS-CoV-2 neutralizing monoclonal antibodies (nMABs) between June and October 2021. Patients exhibited serological vaccination failure or were unable to clear SARS-CoV-2 even after prolonged infections. Two patients presented with persistent COVID-19 for more than three months. One patient suffered from a third episode of COVID-19 despite vaccination and one patient was diagnosed by SARS-CoV-2 viremia and a positive PCR from the lower respiratory tract while subsequent nasopharyngeal swabs remained negative. In the six described cases, passive immunization with nMABs resulted in rapid and sustained clinical improvement and decrease in viral loads. SARS-CoV-2 nMABs provide a highly attractive treatment option for COVID-19 patients unable to mount a humoral immune response following vaccination or infection.