ABSTRACT
Purpose: This study aims to compare the immunogenicity of a third dose of the heterologous BNT262b2 mRNA vaccine versus the homologous inactivated wholevirion CoronaVac vaccine in adult kidney transplant recipients (KTR). Method(s): This prospective, single-center, phase 4 interventional study included KTR aged 30-69 years, with more than 30days of transplantation, and no previous confirmed COVID-19. The patients received the 3rd heterologous (BNT162b2 mRNA) or homologous dose, at least four weeks after the standard two-dose schedule of CoronaVac vaccine, at the transplant center. Antibody response immediately before and after the 3rd dose was assessed by the AdviseDx SARS-CoV-2 IgG II assay. For those positive assays, neutralizing anti-SARS-CoV-2 antibodies were assessed through the cPassTM SARS-CoV-2 Neutralization Antibody Detection Kit. Result(s): There were 307 patients in the heterologous group and 777 patients in the homologous group. KTR in the heterologous group were older (median age 54 vs. 50 years,p<0.0001), with a lower prevalence of diabetes (7% vs. 11%,p=0.032), lower percentage of deceased donors (60% vs. 68%,p=0.006) and longer time since transplant (median 11 vs. 6 years,p< 0.0001).Immediately before the 3rd dose, seroprevalence for IgG antibodies (36% vs. 34%,p=0.597) and the median antibody titers among those seroprevalent (246 AU/mL vs. 268 AU/mL,p=0.279) were similar. At a median of 25 days after the heterologous and 35 days after the homologous 3rddose vaccine, seroconversion rate was higher in the heterologous group (49% vs. 32%,p<0.0001), resulting in a higher seroprevalence rate (67% vs. 55%,p=0.0003). Overall, 42% remained seronegative after the third dose. The median antibody titers after booster among those seroprevalent patients was higher in those in whom the 3rd heterologous vaccine was administered (7,771 AU/mL vs 599 AU/mL,p<0.0001). The analysis of the neutralizing activity is ongoing. Conclusion(s): This prospective interventional study suggests that a 3rd heterologous dose is associated with a higher seroconversion rate and median antibody titers compared to a homologous dose in kidney transplant recipients fully vaccinated with inactivated whole-virion CoronaVac vaccine. In addition, 42% of subjects did not produce humoral immune response after the third dose, urging the development of alternative strategies.
ABSTRACT
Purpose: This study aimed to investigate the clinical consequences at 3 months after symptom onset among kidney transplant recipients surviving COVID-19. Method(s): This is an ongoing single-center observational prospective study including adult kidney transplant recipients who were diagnosed and survived after COVID-19 between 03/20/2020 and 05/31/2021. Patients who lost their graft were excluded. The patients are scheduled to receive a telephone contact at 3 months after symptom onset from the clinical research team. The call consisted of a structured questionnaire of symptoms with binary answers (yes or no). The questionnaire included the following symptoms: headache, dizziness, anosmia/ageusia, weakness, myalgia, inappetence, diarrhea, and dyspnea, which could be presented before and/or after the COVID-19 diagnosis. Those patients with at least one symptom presented only after the disease, were defined as having Long-COVID-19. Subsequently, the clinical research team included a question about the work status. Adjusted multivariable logistic regression models were used to identify the risk factors associated with Long-COVID-19. Result(s): There were 1,731 patients with COVID-19, with 455 deaths and 36 graft losses. Of the remaining 1,240 patients, 454 (36%) didn't answer our calls, yielding a final cohort of 786 patients. Of them, 217 (28%) developed Long-COVID-19. The incidence of each symptom at 3 months was: dyspnea (7%), myalgia (12%), weakness (11%), headache (10%), dizziness (7%), diarrhea (4%), inappetence (4%) and anosmia/ageusia (3%). About 1% of our patients needed domiciliary O2. Of those who we obtained the working status (n=239), 95 (40%) were employed before COVID-19 and 79 of them (83%) had returned to their original work at 3 months. After COVID-19 diagnosis, 44% of the patients were hospitalized (31% in ICU), 35% used supplemental O2, and 5% required mechanical ventilation. Fever (53%), shiver (39%), nausea (3%), anosmia/ageusia (59%), hospitalization (67%), and adverse cardiovascular events (3%), such as thrombosis or myocardial infarction, were risk factors associated with subsequent development of Long-COVID-19, using adjusted multivariable logistic regression. Conclusion(s): The incidence of Long-COVID-19 at 3 months was 28% and was associated with reduced quality of life and return to work. Several COVID-19 associated symptoms and disease severity markers were associated with Long- COVID-19.