Eculizumab clearance and sC5b-9 change over the doses of therapy.PK and PD changes across treatment doses were evaluated using individual eculizumab clearance estimates (A) and predose sC5b-9 levels (B). Eculizumab individual clearance values at each week were estimated by the Bayesian estimation method with consideration of interoccasion variability and adjusted by an allometrically scaled body weight of 70 kg. Because the study included a wide age range (0.5-29.9 years), the effect of an increase in body size on eculizumab clearance was taken into account by adjusting it by allometric scaling to a body weight of 70 kg to allow for a comparison across pediatric and young adult patients with different body sizes as previously described.⁷  Eculizumab clearance estimates and changes in sC5b-9 level over time were analyzed by 1-way analysis of variance (R, ver. 3.0.3).