Immune Response to Third Dose BNT162b2 COVID-19 Vaccine Among Kidney Transplant Recipients—A Prospective Study
Dafna Yahav, Ruth Rahamimov, Tiki Mashraki, Naomi Ben-Dor, Tali Steinmetz, Timna Agur, Борис Зингерман, Michal Herman‐Edelstein, Shelly Lichtenberg, Haim Ben‐Zvi, Erez Bar‐Haim, Hila Cohen, Shahar Rotem, Uri Elia, Ili Margalit, Benaya Rozen Zvi
Abstract
Immune response to two SARS-CoV-2 mRNA vaccine doses among kidney transplant recipients (KTRs) is limited. We aimed to evaluate humoral and cellular response to a third BNT162b2 dose. In this prospective study, 190 KTRs were evaluated before and ∼3 weeks after the third vaccine dose. The primary outcomes were anti-spike antibody level >4160 AU/ml (neutralization-associated cutoff) and any seropositivity. Univariate and multivariate analyses were conducted to identify variables associated with antibody response. T-cell response was evaluated in a subset of participants. Results were compared to a control group of 56 healthcare workers. Among KTRs, we found a seropositivity rate of 70% (133/190) after the third dose (37%, 70/190, after the second vaccine dose); and 27% (52/190) achieved levels above 4160 AU/ml after the third dose, compared to 93% of controls. Variables associated with antibody response included higher antibody levels after the second dose (odds ratio [OR] 30.8 per log AU/ml, 95% confidence interval [CI]11–86.4, p < 0.001); and discontinuation of antimetabolite prior to vaccination (OR 9.1,95% CI 1.8–46.5, p = 0.008). T-cell response was demonstrated in 13% (7/53). In conclusion, third dose BNT162b2 improved immune response among KTRs, however 30% still remained seronegative. Pre-vaccination temporary immunosuppression reduction improved antibody response.