Given that B-cell-directed mAbs have demonstrated efficacy in several autoimmune CNS diseases, investigator-initiated and industry-funded basket studies appear to be a reasonable approach to generating higher quality data for treatment-refractory MS or AQP4-positive NMOSD, and for individuals with MOGAD and AE who choose to participate in a study rather than receiving off-label therapy. Here, AQP4 is linked to myeloid sarcoma.