Key studies for preemptive rituximab strategy in iTTP management
| Study . | Population . | Without preemptive rituximab . | Preemptive rituximab treatment . |
|---|---|---|---|
| Hie et al7 | 233 French iTTP patients with >1 y of follow-up (2000-2012). 48 had ADAMTS13 < 10% during follow-up; of these, 30 received preemptive rituximab, 375 mg/m2 (1, 2, or 4 infusions). | TTP recurrence: 0.57 episodes per year (IQR, 0.46-0.70) | At 3 mo posttreatment: ADAMTS13 recovery‡‡ in 87%. No TTP recurrence episode per year (IQR, 0-0.81). Subsequent retreatment with preemptive rituximab necessary in 30%. |
| Retrospective* | |||
| Jestin et al8 | 92 French iTTP patients with >1 y of follow-up (2012-2017). 92 with ADAMTS13 < 10% during follow-up. 92 received preemptive rituximab 375-500 mg/m2 (1-4 infusions). | TTP recurrence: 0.33 episodes per year (IQR, 0.23-0.66) | At 3 mo posttreatment: ADAMTS13 recovery‡‡ in 86%. No TTP recurrence episodes per year (IQR 0-1.32). Recurrence of ADAMTS13 < 10% in 45/79 (57%) patients. Subsequent retreatment with preemptive rituximab in 48% of patients. |
| Prospective* | |||
| Westwood et al9 | 45 British iTTP patients with 76 episodes of ADAMTS13 <= 15% (2005-2016) received preemptive rituximab: 375 mg/m2 (n = 24; 4 infusions) or 500-mg fixed dose (n = 17; 4 infusions), 200-mg fixed dose (n = 19; 4 infusions), or various dose regimens (n = 16) | TTP recurrence incidence not reported | At 1 mo posttreatment, ADAMTS13 recovery‡‡ in 92%. 20/45 (44.4%) patients received ≥ 2 preemptive treatments with rituximab. |
| Retrospective†† |
| Study . | Population . | Without preemptive rituximab . | Preemptive rituximab treatment . |
|---|---|---|---|
| Hie et al7 | 233 French iTTP patients with >1 y of follow-up (2000-2012). 48 had ADAMTS13 < 10% during follow-up; of these, 30 received preemptive rituximab, 375 mg/m2 (1, 2, or 4 infusions). | TTP recurrence: 0.57 episodes per year (IQR, 0.46-0.70) | At 3 mo posttreatment: ADAMTS13 recovery‡‡ in 87%. No TTP recurrence episode per year (IQR, 0-0.81). Subsequent retreatment with preemptive rituximab necessary in 30%. |
| Retrospective* | |||
| Jestin et al8 | 92 French iTTP patients with >1 y of follow-up (2012-2017). 92 with ADAMTS13 < 10% during follow-up. 92 received preemptive rituximab 375-500 mg/m2 (1-4 infusions). | TTP recurrence: 0.33 episodes per year (IQR, 0.23-0.66) | At 3 mo posttreatment: ADAMTS13 recovery‡‡ in 86%. No TTP recurrence episodes per year (IQR 0-1.32). Recurrence of ADAMTS13 < 10% in 45/79 (57%) patients. Subsequent retreatment with preemptive rituximab in 48% of patients. |
| Prospective* | |||
| Westwood et al9 | 45 British iTTP patients with 76 episodes of ADAMTS13 <= 15% (2005-2016) received preemptive rituximab: 375 mg/m2 (n = 24; 4 infusions) or 500-mg fixed dose (n = 17; 4 infusions), 200-mg fixed dose (n = 19; 4 infusions), or various dose regimens (n = 16) | TTP recurrence incidence not reported | At 1 mo posttreatment, ADAMTS13 recovery‡‡ in 92%. 20/45 (44.4%) patients received ≥ 2 preemptive treatments with rituximab. |
| Retrospective†† |
TTP, thrombotic thrombocytopenic purpura.
Treatment trigger: ADAMTS13 < 10%.
†Treatment trigger: ADAMTS13 ≤ 15%. In 2 instances, treatment was initiated when ADAMTS13 activity was 16% and 17%.
‡ADAMTS13 recovery was reported differently in the 3 studies: In Hie et al,7 median ADAMTS13 activity at 3 months was 46% (IQR, 30-68). Jestin et al8 documented ADAMTS13 activity in 76 of 79 patients; it was normal in 56% (42/76) of patients and moderately decreased in 30% (23/76) of patients. In Westwood et al,9 ADAMTS13 ≥ 30% in 70/76 (92%) episodes; complete remission as ADAMTS13 activity ≥ 60% in 60/76 (79%) episodes, and partial remission as ADAMTS13 activity in 30% to 59% in 10/76 (13%) episodes.