Caplacizumab and Immunosuppressive Therapy Without Firstline Therapeutic Plasma Exchange in Adults With Immune-mediated Thrombotic Thrombocytopenic Purpura

Remission was defined as sustained clinical response with either no TPE and no anti- von Willebrand factor (vWF) therapy for >=30 days (clinical remission) or with attainment of a disintegrin and metalloproteinase with a thrombospondin type 1 motif13 (ADAMTS13) activity level >=50% (complete ADAMTS13 remission), whichever occurred first. Clinical response was defined as sustained platelet count >=150 × 10^9/liter (L) and lactate dehydrogenase (LDH) <1.5 × upper limit of normal (ULN) and no clinical evidence of new or progressive ischemic organ injury for at least 2 consecutive visits.

Remission was defined as sustained clinical response with either no TPE and no anti- vWF therapy for >=30 days (clinical remission) or with ADAMTS13 activity level >=50% (complete ADAMTS13 remission), whichever occurred first. Clinical response was defined as sustained platelet count >=150 × 10^9/L and LDH <1.5 × ULN and no clinical evidence of new or progressive ischemic organ injury for at least 2 consecutive visits.

TPE was a procedure in which blood of the participant was passed through a medical device which separated out plasma from other components of blood and the participant's plasma was removed and replaced with a replacement solution such as colloid solution (example, albumin and/or plasma) or a combination of crystalloid/colloid solution. TPE replenishes the ADAMTS13 enzyme and removes anti-ADAMTS13 antibodies, and ultra-large von Willebrand factor multimers gradually from the circulation.

An AE was any untoward medical occurrence in a participant or clinical study participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. TEAEs were defined as the AEs that developed, worsened or became serious during the treatment-emergent period. SAE: Any untoward medical occurrence that at any dose: resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, or was a congenital anomaly/birth defect, or any other situation where medical or scientific judgment of investigator were exercised. An AESI is an AE (serious or nonserious) of scientific and medical concern specific to the Sponsor's product or program, for which ongoing monitoring and immediate notification by the Investigator to the Sponsor was required.

Clinical response was defined as sustained platelet count >=150 × 10^9/L and LDH <1.5 × ULN and no clinical evidence of new or progressive ischemic organ injury for at least 2 consecutive visits.

Clinical response was defined as sustained platelet count >=150 × 10^9/L and LDH <1.5 × ULN and no clinical evidence of new or progressive ischemic organ injury for at least 2 consecutive visits.

Time to platelet count response was defined as time from start of study treatment to initial platelet count >=150 × 10^9/L that was sustained for >=2 days.

Refractory to therapy was defined as lack of sustained platelet count increment (over 2 consecutive days) or platelet counts <50 × 10^9/L and persistently elevated LDH (>1.5 × ULN) despite 5 days of treatment during the on-treatment period.

Percentage of participants with iTTP-related death during on-treatment period are reported.

Percentage of participants with iTTP-related death during overall study period are reported.

Clinical exacerbation was defined as after a clinical response and before a clinical remission, platelet count decreased to <150 × 10^9/L (with other causes of thrombocytopenia excluded), with or without clinical evidence of new or progressive ischemic organ injury, within 30 days of stopping TPE or anti-vWF therapy.

Clinical exacerbation was defined as after a clinical response and before a clinical remission, platelet count decreased to <150 × 10^9/L (with other causes of thrombocytopenia excluded), with or without clinical evidence of new or progressive ischemic organ injury, within 30 days of stopping TPE or anti-vWF therapy.

Clinical relapse was defined as after a clinical remission, platelet count decreased to <150 × 10^9/L (with other causes of thrombocytopenia ruled out), with or without clinical evidence of new ischemic organ injury. A clinical relapse had to be confirmed by documentation of severe ADAMTS13 deficiency (<10%).

Clinical relapse was defined as after a clinical remission, platelet count decreased to <150 × 10^9/L (with other causes of thrombocytopenia ruled out), with or without clinical evidence of new ischemic organ injury. A clinical relapse had to be confirmed by documentation of severe ADAMTS13 deficiency (<10%).