Long-Term Safety and Efficacy of Caplacizumab for Acquired Thrombotic Thrombocytopenic Purpura (aTTP): The Post-HERCULES Study

Abstract Background: The post-HERCULES trial (NCT02878603) evaluated long-term safety and efficacy of caplacizumab in patients with acquired thrombotic thrombocytopenic purpura (aTTP; also known as immune-mediated TTP), and efficacy of repeated use of caplacizumab for aTTP recurrence. Methods: Patients who completed the HERCULES trial were invited to participate in the post-HERCULES study and attend twice-yearly visits for 3 years. In case of aTTP recurrence, patients could receive open-label (OL) caplacizumab with therapeutic plasma exchange (TPE) and immunosuppression (IST). Safety was assessed during the overall study period (intention-to-observe [ITO] population) and during recurrences.…