Figure 1.

Phase IIa study. (a) Design per original protocol. (b) Study flow diagram of phase IIa study. (c) Study flow diagram of phase III open‐label extension (OLE) study. D, day; PK, pharmacokinetic; W, week. Only data from the subset of patients aged ≥ 6 to < 12 years are reported in this article. ^aPart A, single dose followed by an 8‐week follow‐up period with semidense sampling for systemic drug concentration. ^bPart B, four weekly doses followed by an 8‐week safety follow‐up period. The analysis presented here focuses on patients aged ≥ 6 to < 12 years who participated in the previous phase IIa study before the data cutoff date of 22 July 2019. Data are presented up to week 52. ^cFor patients who completed part A per schedule, day‐1 visit of part B was the same visit as week‐8 visit of part A. For patients who did not complete part A per schedule (e.g. patients who received systemic corticosteroid or systemic nonsteroidal immunosuppressive drugs as rescue within 2 weeks of scheduled start of repeat dose and required 2 weeks of washout of the rescue medication), week‐8 visit of part A and day‐1 visit of part B were two independent visits; these patients were to complete the week‐8 visit of part A and start visits for part B independent of part A. ^dOn visits in which study drug administration was planned, patients had the option to come to the clinic to have the study drug administered by site staff. ^eIn‐clinic visits occurred every 3 months.