Analysis of Risk Factors for a Low Immune Response to Messenger RNA COVID-19 Vaccine in Kidney Transplant Recipients and Differences Between Second and Third Dose

Abstract

INTRODUCTIONThe efficacy of the response to SARS-CoV-2 vaccination in kidney transplant recipients is low. The aim of our study was to evaluate the risk factors correlated with the low antibody response and whether there was an improvement between the second and the third dose.MATERIALS AND METHODSA prospective study was conducted on 176 kidney transplant recipients, who received the second and the third dose of the anti-SARS-CoV-2 mRNA Comirnaty vaccine. We evaluated the seroconversion process after administration of the second and the third dose and assessed a possible correlation with age, time between transplantation and vaccination and type of immunosuppressive therapy.RESULTS98 out of the 176 (55.7%) patients responded positively after the inoculation of the second dose and according to the multivariable logistic regression analysis the lack of seroconversion was independently associated with patient age ≥60 (p=0.025, OR=2.094), time since transplantation of 1-3 months (p=0.032, OR=2.118) and triple therapy (p=0.044, OR=2.327). After the vaccine third dose the seroconversion increased to 62.5% and it was negatively influenced by Calcineurin inhibitors (CNI) use (12/21, 57.1% vs. 71/78, 91.0%, p=0.0006), and triple therapy (13/21, 61.9% vs. 72/78, 92.3%, p=0.0014). The median of anti-spike Ab response significantly increased from 18.5UI/ml after the 2nd dose to 316.9UI after the 3rd dose (p<0.0001).DISCUSSION AND CONCLUSIONSWe demonstrated a correlation between older age, short distance from the transplant and triple immunosuppressive therapy with the lack of seroconversion. We noticed a significant improvement in antibody response by a third dose of mRNA vaccine.