TNFSF13B and relapsing-remitting multiple sclerosis: In contrast, tabalumab, an anti-BAFF monoclonal targeting BAFF, mainly affecting transitional and mature B cells while sparing memory B cells, had no clinical effect in RRMS patients (20) Instead, treatment with tabalumab led to an increase in circulating memory B cells, further underscoring the importance of memory B-cell depletion for therapeutic efficacy (21).