A phase‐II sequential case‐series study of all patients presenting to four plasma exchange centres with presumed relapsed/refractory thrombotic thrombocytopenic purpura treated with rituximab. (8th April 2015)

• Record Type: Journal Article
• Authors: Clark, William F.; Rock, Gail; Barth, David; Arnold, Donald M.; Webert, Kathyrn E.; Yenson, Paul R.; Kelton, John G.; Li, Lihua; Foley, Steven R.; members of the Canadian Apheresis Group
• Is Part Of: British journal of haematology. Volume 170:Number 2(2015:Jul.)
• Page Start: 208
• Page End: 217
• Publication Date: 2015-04-08
• Subjects: Hematology -- Periodicals; Blood -- Diseases -- Periodicals; 616.15
• DOI: 10.1111/bjh.13408
• Languages: English
• ISSNs: 0007-1048

Abstract

<abstract abstract-type="main" id="bjh13408-abs-0001"> <title>Summary</title> <p>The primary objective of this phase II study was to evaluate the efficacy of rituximab in the management of adult patients with physician‐diagnosed presumed thrombotic thrombocytopenic purpura (TTP); relapsed or refractory. We conducted a multicentre study in four Canadian hospital‐based apheresis units. Forty patients with presumed TTP (20 refractory and 20 relapsing) were sequentially enrolled and all received rituximab in a standardized manner. A complete response was documented in 14 of 19 refractory patients by week 8 and 15/16 were alive and in remission at 52 weeks (one patient was lost to follow‐up, one was a non‐responder, and three died). Among relapsing patients, 16/18 had a complete response at week 8 and 18/18 at week 52 (one patient lost to follow‐up and one withdrew). At 1 year, all relapsing and 85% of refractory patients survived. Of 38/40 patients who had ADMATS13 testing at study entry, 13/19 refractory and 10/19 relapsing patients had ADAMTS13 &lt; 10% (typical TTP); whereas 6/19 refractory and 9/19 relapsing cases had ADAMTS13 &gt; 10% (other thrombotic microangiopathy; TMA). Refractory‐typical TTP in contrast to refractory‐other TMA and all relapsing patients treated with plasma exchange and rituximab, were less likely to be responsive and more likely to die or relapse.</p> </abstract>