Covalent and non-covalent BTK inhibitors seem as a class to be effective against EBV-associated CNS lymphomas and post-transplant lymphoproliferatives disorders and reduce EBV viral loads.156,157 BCR signalling, which activates EBV lytic induction in freshly isolated B cells from peripheral blood mononuclear cells (PBMCs) can be inhibited by BTKi's ibrutinib or idelalisib.158 Several second-generation BTK inhibitors, some of which have been shown to be CNS penetrant, are in late-stage development as treatments for MS.159 One of the modes of action of BTKs may therefore be against EBV. This evidence concerns the gene BTK and lymphoproliferative syndrome.