Seroresponse to third doses of SARS-CoV-2 vaccine among patients receiving maintenance dialysis

Given the increased morbidity and mortality from COVID-19 among patients undergoing maintenance dialysis, we examined the seroresponse to an additional dose of SARS-CoV-2 mRNA vaccine, using a hypothesized protective anti-spike protein IgG antibody threshold of 7 based on prior work. Among 395 patients, 384 (97%) had seroresponse ≥7 following administration of the third dose. Among those with suboptimal (peak <7) and minimal (peak <1) seroresponse to an initial mRNA vaccine regimen, the rate of seroresponse ≥7 following a third dose was 97% (36 of 37) and 64% (14 of 22), respectively. Given ongoing high rates of COVID-19 and rapidly waning immunity after an initial vaccine series, we recommend a third mRNA vaccine dose be standard for all patients receiving maintenance dialysis.