title: Efficacy and Safety of Rituximab for Refractory and Relapsing Thrombotic Thrombocytopenic Purpura: A Cohort of 10 Cases.
abstract: OBJECTIVE
  Idiopathic thrombotic thrombocytopenic purpura (TTP) is a life-threatening disorder mediated by autoantibodies directed against ADAMTS13. This provides a rationale for the use of rituximab in this disorder. We report our experience and the outcome of 10 cases of TTP (9 refractory and 1 relapsing) successfully treated with rituximab in combination with plasma exchange (PE) and other immunosuppressive treatments.
  
  
  METHODS
  The diagnosis of TTP was based on clinical criteria and supported by severe deficiency of ADAMTS13 activity and presence of inhibitors in seven cases. Rituximab was started after a median of 18.6 sessions of PE (range: 5-35) at the dose of 375 mg/m(2)/week for 4-8 weeks.
  
  
  RESULTS
  Complete remission was achieved in all patients after a median time of 14.4 days of the first dose (range: 6-30). After a median follow-up of 30 months (range: 8-78), eight patients were still in remission and two developed multiple relapses, treated again with the same therapy, and achieved complete responses; they are alive, and in complete remission after a follow-up of 12 and 16 months.
  
  
  CONCLUSIONS
  Rituximab appears to be a safe and effective therapy for refractory and relapsing TTP. However, longer follow-up is recommended to assess relapse and detect possible long-term side effects of this therapy.
authors.affiliation: Medical Oncology Department, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Halima El
authors.initials: HE
authors.lastname: Omri
authors.affiliation: Medical Oncology Department, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Ruba Y
authors.initials: RY
authors.lastname: Taha
authors.affiliation: Medical Oncology Department, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Amna
authors.initials: A
authors.lastname: Gamil
authors.affiliation: Department of Laboratory Medicine and Pathology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Firyal
authors.initials: F
authors.lastname: Ibrahim
authors.affiliation: Medical Oncology Department, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Hisham Al
authors.initials: HA
authors.lastname: Sabah
authors.affiliation: Blood Bank Center, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Zeinab O
authors.initials: ZO
authors.lastname: Mahmoud
authors.affiliation: Medical Oncology Department, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Pittari
authors.affiliation: Medical Oncology Department, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Ibrahim Al
authors.initials: IA
authors.lastname: HIjji
authors.affiliation: Medical Oncology Department, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Yassin
keywords: TTP; plasma exchange; refractory; relapse; rituximab