Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Purpose: This study aimed to investigate whether the serum extracellular newly identified receptor for advanced glycation end products binding protein (EN-RAGE) and the soluble form of RAGE (sRAGE) measured at diagnosis are associated with all-cause mortality in patients with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA). Materials and Methods: Serum EN-RAGE and sRAGE were measured in 75 immunosuppressive drug-naïve MPA and GPA patients using an immunoassay, with their clinical and laboratory data reviewed. The optimal cut-off point of EN-RAGE and sRAGE was calculated by finding the threshold with the maximum sum of sensitivity and specificity. In addition, the least absolute shrinkage and selection operator regression was adopted to select variables included in the multivariable Cox proportional hazards (PH) regression model. Results: The median age of the patients was 67.0 years, and 34% were male. Neither serum EN-RAGE nor sRAGE at diagnosis was correlated with the Birmingham Vasculitis Activity Score. Furthermore, no correlation was observed between serum EN-RAGE and sRAGE. Deceased patients had significantly lower serum EN-RAGE and higher serum sRAGE at diagnosis compared to surviving patients. Patients with serum EN-RAGE at diagnosis ≤84.37 ng/mL and serum sRAGE at diagnosis ≥1.82 ng/mL showed significantly lower survival probabilities compared to those without. In multivariable Cox PH regression model, only serum sRAGE at diagnosis ≥1.82 ng/mL, rather than serum EN-RAGE at diagnosis ≤84.37 ng/mL, was independently associated with all-cause mortality (hazard ratio 7.094). Conclusion This study is the first to demonstrate that serum sRAGE at diagnosis may independently predict all-cause mortality during follow-up in patients with MPA and GPA.

Purpose: This study aimed to investigate whether the serum extracellular newly identified receptor for advanced glycation end products binding protein (EN-RAGE) and the soluble form of RAGE (sRAGE) measured at diagnosis are associated with all-cause mortality in patients with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA). Materials and Methods: Serum EN-RAGE and sRAGE were measured in 75 immunosuppressive drug-naïve MPA and GPA patients using an immunoassay, with their clinical and laboratory data reviewed. The optimal cut-off point of EN-RAGE and sRAGE was calculated by finding the threshold with the maximum sum of sensitivity and specificity. In addition, the least absolute shrinkage and selection operator regression was adopted to select variables included in the multivariable Cox proportional hazards (PH) regression model. Results: The median age of the patients was 67.0 years, and 34% were male. Neither serum EN-RAGE nor sRAGE at diagnosis was correlated with the Birmingham Vasculitis Activity Score. Furthermore, no correlation was observed between serum EN-RAGE and sRAGE. Deceased patients had significantly lower serum EN-RAGE and higher serum sRAGE at diagnosis compared to surviving patients. Patients with serum EN-RAGE at diagnosis ≤84.37 ng/mL and serum sRAGE at diagnosis ≥1.82 ng/mL showed significantly lower survival probabilities compared to those without. In multivariable Cox PH regression model, only serum sRAGE at diagnosis ≥1.82 ng/mL, rather than serum EN-RAGE at diagnosis ≤84.37 ng/mL, was independently associated with all-cause mortality (hazard ratio 7.094). Conclusion This study is the first to demonstrate that serum sRAGE at diagnosis may independently predict all-cause mortality during follow-up in patients with MPA and GPA.