ABSTRACT
BACKGROUND: Comparative studies of third heterologous doses following the CoronaVac vaccine against coronavirus disease 2019 (COVID-19) in kidney transplant recipients are lacking. METHODS: This prospective, single-center cohort study included kidney transplant recipients without previous COVID-19. Patients received a third heterologous (BNT162b2 mRNA) or homologous dose at least 4 wk after 2 doses of the CoronaVac vaccine. Immunoglobulin G antibody response and seroprevalence for neutralizing anti-severe acute respiratory syndrome coronavirus 2 antibodies immediately before and 28 d after third doses were compared between the groups. RESULTS: There were 307 patients in the heterologous group and 777 in the homologous group. Patients in the heterologous group were older (54 versus 50 y; P < 0.0001), with a longer time since transplant (11 versus 6 y; P < 0.0001). Immediately before the third dose, immunoglobulin G seroprevalence (36% versus 34%; P = 0.597) and antibody titers (246 versus 268 AU/mL; P = 0.279) were similar. After booster, seroconversion was higher in the heterologous group (49% versus 32%; P < 0.0001), resulting in a higher seroprevalence (67% versus 55%; P = 0.0003); however, 42% of all patients remained seronegative. Antibody titers after booster in seropositive patients were higher in the heterologous group (7771 versus 599 AU/mL; P < 0.0001). These results persisted after adjusting for confounding variables. Lastly, a similar proportion of patients became seropositive for neutralizing antibodies (98% versus 94%; P = 0.098). CONCLUSIONS: In kidney transplant recipients fully vaccinated with CoronaVac, a third dose with an mRNA vaccine produced a higher seroconversion rate and antibody titers than a third homologous dose. However, both boosters achieved equivalent seroprevalence for neutralizing antibodies. The high proportion of still seronegative patients indicates the need for alternative strategies of protection.
Subject(s)
COVID-19 Vaccines , COVID-19 , Immunization, Secondary , Kidney Transplantation , Transplant Recipients , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Cohort Studies , Humans , Immunization, Secondary/adverse effects , Immunoglobulin G , Kidney Transplantation/adverse effects , Prospective Studies , Seroepidemiologic Studies , Vaccines, Synthetic , mRNA VaccinesABSTRACT
BACKGROUND: Anti-severe acute respiratory syndrome coronavirus 2 mRNA vaccines elicit lower humoral responses in solid-organ transplant recipients. This is the first prospective trial investigating the effect of an inactivated whole-virion vaccine in kidney transplant recipients. METHODS: Prospective, single-center, phase 4, interventional study. Kidney transplant recipients aged 30-69 y with >30 d of transplantation received two 3 µg intramuscular doses of CoronaVac 28 d apart and are being followed for 6 mo. Primary outcomes: (1) reactogenicity after first dose; (2) antibody responses 28 d after each dose; and (3) incidence/severity of confirmed coronavirus disease 2019 (COVID-19) and 28-d lethality rate. For this analysis, clinical effectiveness was assessed for 3 mo, starting 15 d after the second dose, and compared with 3-mo period before vaccination. RESULTS: Of the 3371 individuals who received the first dose, 99% completed vaccination schedule. Mild/local adverse reactions were reported by 33% of the patients. In the immunogenicity cohort (n = 942), the proportion of patients with IgG antibodies to severe acute respiratory syndrome coronavirus 2 increased from 15.2% after first dose to 43% after second dose. Increase in antibody values after second dose was associated with higher proportion of patients with detected neutralizing antibodies. A significant reduction in the incidence of COVID-19 was observed (6.4% versus 4.2%; P < 0.0001), although the 28-d lethality rate remained unchanged (25% versus 22%; P = 0.534). In 45 patients from the immunogenicity cohort who developed COVID-19, all the 6 deaths occurred among those without antibody response (n = 22; 49%). CONCLUSIONS: CoronaVac vaccine was associated with low reactogenicity, low immunogenicity but reduced incidence of COVID-19 among kidney transplant recipients. The lack of reduction in lethality rates is perhaps associated with the low percentage of patients developing humoral response after the second dose.
Subject(s)
COVID-19 , Kidney Transplantation , Adult , Aged , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/epidemiology , COVID-19/prevention & control , Humans , Kidney Transplantation/adverse effects , Middle Aged , Prospective Studies , SARS-CoV-2 , Vaccines, Inactivated/immunologyABSTRACT
Background. Anti-severe acute respiratory syndrome coronavirus 2 mRNA vaccines elicit lower humoral responses in solid-organ transplant recipients. This is the first prospective trial investigating the effect of an inactivated whole-virion vaccine in kidney transplant recipients. Methods. Prospective, single-center, phase 4, interventional study. Kidney transplant recipients aged 30–69 y with >30 d of transplantation received two 3 µg intramuscular doses of CoronaVac 28 d apart and are being followed for 6 mo. Primary outcomes: (1) reactogenicity after first dose; (2) antibody responses 28 d after each dose; and (3) incidence/severity of confirmed coronavirus disease 2019 (COVID-19) and 28-d lethality rate. For this analysis, clinical effectiveness was assessed for 3 mo, starting 15 d after the second dose, and compared with 3-mo period before vaccination. Results. Of the 3371 individuals who received the first dose, 99% completed vaccination schedule. Mild/local adverse reactions were reported by 33% of the patients. In the immunogenicity cohort (n = 942), the proportion of patients with IgG antibodies to severe acute respiratory syndrome coronavirus 2 increased from 15.2% after first dose to 43% after second dose. Increase in antibody values after second dose was associated with higher proportion of patients with detected neutralizing antibodies. A significant reduction in the incidence of COVID-19 was observed (6.4% versus 4.2%; P < 0.0001), although the 28-d lethality rate remained unchanged (25% versus 22%; P = 0.534). In 45 patients from the immunogenicity cohort who developed COVID-19, all the 6 deaths occurred among those without antibody response (n = 22; 49%). Conclusions. CoronaVac vaccine was associated with low reactogenicity, low immunogenicity but reduced incidence of COVID-19 among kidney transplant recipients. The lack of reduction in lethality rates is perhaps associated with the low percentage of patients developing humoral response after the second dose.
