Immunogenicity of SARS-CoV-2 Vaccine in Dialysis

Lacson, Eduardo; Argyropoulos, Christos; Manley, Harold; Aweh, Gideon; Chin, Andrew; Salman, Loay; Hsu, Caroline; Johnson, Doug; Weiner, Daniel

BACKGROUND: Patients receiving maintenance dialysis represent a high risk, immune-compromised population with 15-25% COVID-19 mortality rate who were unrepresented in clinical trials of mRNA vaccines. METHOD: All patients receiving maintenance dialysis who received two doses of SARS-CoV-2 mRNA vaccines with antibody test results drawn ≥14 days after the second dose, as documented in the electronic health record through March 18, 2021, were included. Response was based on levels of immunoglobulin-G against the receptor binding domain of the S1 subunit of SARS-CoV-2 spike-antigen (seropositive ≥2 U/L) using an FDA-approved semi-quantitative chemiluminescent assay (ADVIA Centaur® XP/XPT COV2G). RESULTS: Among 186 dialysis patients from 30 clinics in 8 states tested 23±8 days after receiving 2 vaccine doses, there were 165 (88.7%) responders with 70% at maximum titer. There was no significant difference between BNT162b2/Pfizer (148/168, 88.1%) and mRNA-1273/Moderna (17/18, 94.4%), p=0.42. All 38 patients with COVID-19 history were responders, with 97% at maximum titer. Among patients without COVID-19, 127/148 (85.8%) were responders, comparable between BNT162b2/Pfizer (113/133) and mRNA-1273/Moderna (14/15) vaccines (85.0% vs. 93.3%, p=0.38). CONCLUSION: Most patients receiving maintenance dialysis responded after two doses of BNT162b2/Pfizer or mRNA-1273/Moderna vaccine, suggesting that the short-term development of anti-spike antibody is good, giving hope that most of these vulnerable patients, once immunized, will be protected from COVID-19. Longer-term evaluation is needed to determine antibody titer durability and if booster dose(s) are warranted. Further research to evaluate the approach to patients without a serologic response is needed, including benefits of additional dose(s) or administration of alternate options.