Humoral response to SARS-CoV-2 vaccination promises to improve the catastrophic prognosis of hemodialysis patients as a result of COVID-19. The COViNEPH Project.

Tylicki, Leszek; Biedunkiewicz, Bogdan; Dąbrowska, Małgorzata; Ślizień, Waldemar; Tylicki, Piotr; Polewska, Karolina; Rosenberg, Iwona; Rodak, Sylwia; Dębska-Ślizień, Alicja

Introduction There is an urgent need to check the efficacy of SARS-CoV-2 vaccination among hemodialyzed (HD) patients known to have extensive disturbances of acquired immunity and a catastrophic risk of death from COVID-19. Objectives In a cross-sectional study we aimed to assess the humoral response following vaccination with the BNT162b2 (BioNTech / Pfizer Comirnaty) vaccine. Patients and methods We analyzed the titer magnitude of the IgG antibodies directed against spike (S)- SARS-CoV-2 antigen 14-21 days after the second dose of the BNT162b2 vaccine in a group of HD patients who have not been confirmed with SARS-CoV-2 infection yet, compared to patients with a history of COVID-19. 126 HD patients were stratified based on evidence of a previous infection with SARS-COV-2 confirmed with viral RNA detection or nucleocapsid-specific IgG antibodies detection. Results s-antigen immune response with a median (IQR) antibody titer of 366 (193-691) UA/ml was seen in 87 of 91 infection naïve (IN)-HD patients (95.6%). In 68 of 91 IN-HD patients (74.7%) a strong humoral response was observed with titer anti-S antibodies above 200 UA/ml. Older subjects were less likely to develop an S-antibodies response (P <0.001). The median S-antigen antibody titer in 35 previously infected (PI)-HD patients was over 12-fold higher than in IN-HD patients; 4620 (1240-7820) UA/ml (P <0.001). There were no significant differences in S-antibody titer between symptomatic and asymptomatic PI-HD patients. Conclusions Our study demonstrated that the majority of HD patients achieved a high immunization rate after vaccination with BNT162b2. Whether this translates into protecting this population from COVID-19 requires further research.