Omicron neutralising antibodies after COVID-19 vaccination in haemodialysis patients

The SARS-CoV-2 variant of concern (VOC) B.1.1.529 omicron is now the predominant VOC in the UK.1 The burden of more than 30 mutations in omicron spike suggests at least a degree of vaccine evasion,2 and UK Health Security Agency estimates of vaccine efficacy against infection are reduced compared to delta.1 The critical question is how well existing vaccines will protect clinically extremely vulnerable groups against infection. In the UK, the COVID-19 death rate for in-centre haemodialysis (IC-HD) patients during the delta wave was 14·65 (95% CI 11·49–18·67) per 1000 patient-years, the highest rate for any OpenSAFELY-defined comorbidity.3 The increased transmissibility of omicron is likely to prove challenging in haemodialysis units, where in-unit transmission with prior VOCs has occurred.4 We therefore sought to determine the neutralising antibody (nAb) titres (nAbTs) in IC-HD patients, a cohort we have previously shown to have attenuated nAb responses to delta.