Approximately half a year after the start of recruitment, the Deutsche Multiple Sklerose Gesellschaft (DMSG), the Kompetenznetz Multiple Sklerose (KKNMS), and the Berufsverband Deutscher Neurologen (BDN) issued a joint statement to clarify that the RKI recommendation should also be applied to MS patients treated with anti-CD20 antibodies or S1P-inhibitors [17]. Here, MBTPS1 is linked to myeloid sarcoma.