The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions. Figure S1: Overall survival in patients with anti-MDA5 antibody-positive RP-ILD. (A) Kaplan–Meier curve showing overall survival for the entire cohort, including the early dropout group (n = 48). (B) Kaplan–Meier survival between the pre-antibody monitoring cohort (n = 13) and the antibody monitoring cohort (n = 23), excluding early dropout cases. MDA5, melanoma differentiation-associated gene 5; RP-ILD, rapidly progressive interstitial lung disease. Figure S2: Longitudinal changes in anti-MDA5 antibody titers. (A) Overall trajectories of anti-MDA5 antibody titers during the entire observation period in both groups. (B) Zoomed-in view limited to patients with titers < 100 to visualize low-titer kinetics. (C) Enlarged view of the first 12 months to illustrate early-phase dynamics. (D) Box-and-whisker plots comparing anti-MDA5 antibody levels between the pre-monitoring and antibody monitoring cohorts at selected time points. In both cohorts, titers declined rapidly after treatment initiation, and no statistically significant between-group differences were observed at comparable time points. MDA5, melanoma differentiation-associated gene 5. Figure S3: Kaplan–Meier analysis of time to GC discontinuation after exclusion of patients receiving JAK inhibitors. Sensitivity analysis excluding patients receiving JAK inhibitors. Kaplan–Meier curves for time to GC discontinuation, with patients treated with JAK inhibitors excluded from the analysis. GC, glucocorticoid; JAK, Janus kinase. Table S1: The comparison of characteristics, background, treatment, and prognosis between two groups. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Abe et al. (2026) studied this question.