Incidence of inhibitor development by EDs and titer. The cumulative incidence of inhibitor development was estimated using the Kaplan-Maier method among those in the safety analysis set (n = 103) according to titer; a high-titer inhibitor was a confirmed inhibitor ≥5 BU/mL, and a low-titer inhibitor was a confirmed inhibitor ≥0.6 and <5 BU/mL. For patients without an inhibitor, follow-up time was censored at the last ED at the time of analysis. The table contains the estimated cumulative incidence of inhibitor development at the 10, 20, and 50 ED milestones.