Cost Analysis of Immunoglobulin Maintenance Treatment of Patients with Chronic Inflammatory Demyelinating Polyneuropathy in Spain

BACKGROUND/OBJECTIVE: Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare, immune-mediated disorder, which causes peripheral nervous system dysfunction. Guidelines recommend maintenance treatment with intravenous (IVIG) or subcutaneous (SCIG) immunoglobulins. Drawbacks for IVIG include the burden of hospital administration, which is less for SCIG, which allows self- or caregiver-assisted administration at home. However, conventional SCIG (c-SCIG) requires more frequent administration than IVIG. Recently, facilitated-SGIG (f-SCIG) was developed, spacing injections so that administration frequency is analogous to IVIG. The aim of this study was to estimate and compare the costs of IVIG, c-SCIG, and f-SCIG for CIDP maintenance treatment in Spain. METHODS: A cost-analysis model based on a decision tree was developed to evaluate the annual cost per patient treated with each immunoglobulin from a societal perspective. Costs considered included direct health costs (pharmaceutical acquisition and administration), non-health costs (transport to hospital), and indirect costs related to labor productivity. All costs were valued in 2024 euros. RESULTS: The annual cost for a patient with CIDP receiving maintenance treatment was €109,212.67 with IVIG, €98,161.97 with c-SCIG, and €98,191.37 with f-SCIG. Across all treatments, direct healthcare costs were the highest. The main driver of the difference between SCIG and IVIG cost was treatment administration (-€10,705.78). Sensitivity analyses were generally consistent with the base case results. CONCLUSIONS: Overall, the findings of this analysis suggest that SCIG may be a cost-saving alternative to IVIG for patients with CIDP requiring maintenance treatment in Spain, with a similar cost between c-SCIG and f-SCIG.