2023 Volume 40 Issue 4 Pages 484-487
Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune peripheral neuropathy characterized by muscle weakness in the extremities. Three immunotherapies (immunoglobulin, corticosteroid, and plasma exchange) have been established as effective, with 70–80% of patients actually responding to treatment. However, there are a certain number of cases with inadequate or resistant response to treatment, and new treatment methods are desired. Potential treatment options include (1) intravenous immunoglobulin therapy combined with intravenous methylprednisolone pulse, (2) fetal Fc receptor (FcRn) inhibitors, (3) anti–CD20 monoclonal antibody (rituximab), and (4) autologous hematopoietic stem cell transplantation (AHSCT).
(1) A pilot study reported that 59% of patients were in remission at 1 year after receiving intravenous immunoglobulin therapy in combination with intravenous methylprednisolone pulse, and a randomized controlled trial (RCT) (OPTIC Study) is currently underway to evaluate the combination therapy. (2) FcRn inhibitors have been shown to reduce blood IgG levels by inhibiting IgG recycling, and two subcutaneous drugs (rozanolixizumab and efgartigimod) are being tested in RCT. (3) Efficacy of rituximab has been reported mainly as case report, and a systematic review and meta–analysis indicated that rituximab is effective or CIDP, although confirmation of its efficacy in RCT remains lacking. The therapeutic efficacy of rituximab is more pronounced in patients with anti–paranode IgG4 antibody–positive CIDP. A RCT has been conducted in Japan for IgG4 antibody–positive CIDP (RECIPE study), and the results are awaited to be announced. (4) AHSCT is expected to restore immune tolerance to self–antigens by “resetting” the immune system, and its efficacy has already been established in multiple sclerosis. In a prospective, open–label study conducted in the U.S., 60 CIDP patients who were resistant or dependent to standard immunotherapies were included. The results showed that 83% of the patients no longer needed immunotherapy and 83% were walking on their own after one year (32% before treatment), indicating that AHSCT is a treatment that can aim for a complete cure of the disease.
