In KTRs on prednisolone and EVR, primary and secondary humoral immune responses were preserved, whereas these responses were absent in KTRs on prednisolone and mycophenolic acid.16 Also, better humoral response rates after 2 COVID-19 vaccinations for KTRs on mTOR inhibitors have been described before.7,12,17,18. This evidence concerns the gene MTOR and COVID-19.