CD79A and myeloid sarcoma: A reduction of IgM levels below the lower limit of normal was reported in 22% and 32% of MS patients who had received 2 or 4 1000 mg-administrations of rituximab, respectively, with higher rates reported for longer exposures to treatment (16, 57), IgM were reduced in 37% of the NMOSD patients at year 5 of treatment, and IgA and IgG were reduced in 30% and 13% of the cases, respectively (58).