Autoimmune TTP: Could Rituximab Prevent Relapse?

Treatment with rituximab does not appear to lead to a significant reduction in the rate of acute autoimmune thrombotic thrombocytopenic purpura (iTTP), according to the results of a recent study.

Patients with iTTP “survive with plasma exchange (PEX), fresh frozen plasma replacement and corticosteroid treatment. Anti-CD20 monoclonal antibody rituximab is increasingly used in patients resistant to conventional PEX or relapsing after an acute bout,” the researchers wrote.

In order to examine the relapse rate and potential influencing factors in patients treated with rituximab since 2003, the researchers conducted a retrospective observational study involving 70 patients treated from January 3003 to November 2014. The number and duration of clinical manifestations were documented, as were laboratory data and treatment of acute episodes.

Overall, the 70 participants had a total of 224 acute episodes over a median period of 8.3 years, with a relapse rate of 2.6% per month, (2.4% observed in women and 3.5% observed in men).

Of the participants with first iTTP episodes, 17 were treated with rituximab and 28 were not. While trends toward lower relapse rates were observed following rituximab treatment, the trends were not significant.

“This analysis does not show a significant reduction of acute iTTP relapses by rituximab given during an acute bout. Initial episodes are characterized by more severe clinical signs compared with the less severe relapses. Furthermore, men suffer significantly more frequent and considerably more serious acute relapses.”

—Michael Potts

Reference:

Falter T, Herold S, Weyer-Elberich V, et al. Relapse rate in survivors of acute autoimmune thrombotic thrombocytopenic purpura treated with or without rituximab [published September 20, 2018]. Thromb Haemost. doi: 10.1055/s-0038-1668545.