Chronic inflammatory demyelinating polyradiculoneuropathy - Emerging treatments

Efgartigimod alfa/hyaluronidase

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is associated with pathogenic IgG auto-antibodies. The neonatal Fc receptor (FcRn) extends the half-life of endogenous IgG by binding and transporting it back to the cell surface to prevent it from being degraded by lysosomes. Efgartigimod alfa is a humanised IgG1-derived Fc fragment that competitively inhibits FcRn. Efgartigimod alfa is available as an intravenous formulation, or a subcutaneous formulation (co-formulated with hyaluronidase). The subcutaneous formulation, efgartigimod alfa/hyaluronidase, is approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) for the treatment of CIDP after positive results from the phase 2 ADHERE trial.[163] However, in June 2025, the US FDA announced that it is evaluating the need for regulatory action after observing a potential safety signal of severe worsening of CIDP in some patients switched from traditional intravenous immunoglobulin (IVIG) to efgartigimod alfa/hyaluronidase.[164] One phase 4 trial is under way to assess the safety and tolerability of transition to efgartigimod alfa/hyaluronidase in patients with CIDP within 1 week of stopping IVIG.[165] The intravenous formulation of efgartigimod alfa is not approved for the treatment of CIDP.

Rozanolixizumab

Rozanolixizumab is a humanised IgG4 monoclonal antibody that binds to FcRn. It is approved by the US FDA and the EMA for the treatment of generalised myasthenia gravis. It has been assessed in a phase 2 trial for CIDP, which did not show efficacy but was well tolerated, with an acceptable safety profile.[166]

Serum neurofilament light chain

Serum neurofilament light chain (sNfL) levels are correlated with axonal damage, and so have the potential to be used as a serum biomarker of disease activity and treatment response in patients with CIDP. Studies have demonstrated that higher sNfL levels are associated with an active disease state (non-responders and patients who relapse after intravenous immunoglobulin withdrawal), and treatment-naive patients beginning induction therapy had higher levels of sNfL than those on maintenance therapy or in long-term remission without treatment. Larger studies will be needed to determine how to potentially utilise this to guide management of CIDP.[153][167][168][169]