The anticipated study duration per participant with the presenting episode therefore is a maximum of about 24 weeks (ie, 1 day of screening + maximum 12 weeks of treatment for the presenting episode + 12 weeks of follow-up).
This is a single group, treatment, Phase 3, open-label, single-arm study to evaluate the efficacy and safety of caplacizumab and immunosuppressive therapy (IST) without firstline therapeutic plasma exchange (TPE) with primary endpoint of remission in male and female participants aged 18 to 80 years with immune-mediated thrombotic thrombocytopenic purpura (iTTP).~The anticipated study duration per participant without a recurrence while on therapy is maximum 24 weeks (ie, approximately 1 day for screening + maximum 12 weeks of treatment for the presenting episode + 12 weeks of follow-up). Participants will have daily assessments during hospitalization and weekly visits for assessments during ongoing treatment with caplacizumab and IST. There will be 3 outpatient visits for assessments during the follow-up period. There will be two additional follow-up visits for participants who do not have ADAMTS13 activity levels of ≥50% at the time of caplacizumab discontinuation.