Graphic representation of comparison of ADAMTS13 activity IgG antibody and ADAMTS13 antigen levels at time of stopping caplacizumab in patients with exacerbation and no exacerbation. ADAMTS13 activity <10 IU/dL has been depicted at a level of 5 IU/dL for clarity on Figure 2. Patients with exacerbation of TTP had a lower ADAMTS13 activity, higher anti-ADAMTS13 antibody level, and lower ADAMTS13 antigen level.