ADAMTS13 activity and anti-ADAMTS13 antibody levels over the 6 months after stopping PEX. The measurements of the median ADAMTS13 activity (A) and anti-ADAMTS13 IgG concentration (B) are shown for both the prednisone- and CSA-treated patients. Patients that suffered an exacerbation or that crossed over from another treatment arm are not included in these graphs. In the prednisone arm of the study, all prednisone was tapered and stopped at the end of month 2, whereas the CSA-treated patients continued with the full-dose treatment throughout the 6-month time period shown.