Clinical remission after eculizumab cessation. Axis origin at aHUS diagnosis. Time from diagnosis to eculizumab therapy indicated in blue, duration of eculizumab therapy indicated in green. Time off eculizumab indicated in red. Nonadherence episode (N), relapse (R), possible relapse (PR), and death (X) indicated. Patients continuing on eculizumab at the time of last follow-up indicated with green arrows. Complement activity as determined by mHam assay is indicated temporally by black arrowheads (positive) and gray arrowheads (negative).