ACALA-R In Predominantly Demyelinating IgM Mediated Neuropathy

Study Summary

In this research study, is combining a new treatment acalabrutinib with a standard treatment, rituximab or other CD20 antibody, to determine whether this combination is safe and effective for participants with Immunoglobulin (Ig) M monoclonal gammopathy of undetermined significance ( IgM MGUS) or Waldenström macroglobulinemia WM related neuropathies. The names of the study drugs involved in this study are/is: * Acalabrutinib * Rituximab or similar CD20 antibody