Correspondence on SARS-CoV-2 vaccination in rituximab-treated patients: evidence for impaired humoral but inducible cellular immune response" by Bonelli et al ."

SARS-CoV-2 vaccination elicited high levels of immunogenicity in immunocompetent people in the original vaccine trials1 2 though recent studies have shown blunted immunogenicity in patients with rheumatic diseases treated with lymphocyte depleting agents.3 4 B-lymphocytes have been implicated in the pathogenesis of anti-neutrophil cytoplasmic antibidy (ANCA)-associated vasculitis (AAV) and B-cell-targeted therapy with rituximab is recognised as an established induction and maintenance strategy in management.5 6 SARS-CoV-2 infection in patients with AAV has been associated with severe outcomes,7 while rituximab has been associated with worse outcomes among patients infected with SARS-CoV-2.8 9 A recent study by Bonelli et al found evidence of an ameliorated humoral response but possible inducible cellular response in five patients treated with rituximab.10 We studied the tolerability and humoral response to the SARS-CoV-2 vaccine series in 48 patients with a diagnosis of AAV. Patients underwent SARS-CoV-2 antispike antibody testing to assess humoral response. Antibody testing was performed using antispike IgG enzyme immunoassay (Roche Elecsys via Quest, DiaSorin Liaison assay via LabCorp or Euroimmun via Hopkins lab). Demographics, clinical information including immunosuppressive therapy were extracted from medical records. Time from last rituximab administration to receipt of the first dose of the vaccine was recorded. We recorded serum creatinine, white blood cell count, serum immunoglobulins, Cluster of CD19 and …