ABSTRACT
The huge impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections on organ transplant recipients makes it necessary to optimise vaccine efficacy in this population. To effectively implement multiple strategies, it is crucial to understand the performance of each type of available vaccine. In our study the antibody titre was measured, and the presence of antibodies against SARS-CoV-2 was evaluated after 90 days of immunisation, furthermore, the differences between hybrid immunity, immunity by vaccination and immunosuppressant type were identified. As a result, of the patients included in this study (n=160), 53% showed antibodies against SARS-CoV-2 at 90 days after the first dose in patients who had completed the vaccination schedule. Antibody titres were higher in patients with hybrid immunity, and the proportion of non-responsive patients was higher among those who received the immunosuppressant Belatacept in their post-transplant regimen (p = 0.01). Only 15% of patients treated with this medicine seroconverted, and patients vaccinated with CoronaVac and treated with Belatacept showed no response. In conclusion, a reduced response to vaccines against SARS-CoV-2 was identified in the transplant population, and this response varied with the type of vaccine administered and the immunosuppressive treatment.