Vincristine as an Adjunct to Therapeutic Plasma Exchange for Thrombotic Thrombocytopenic Purpura: A Single Institution Experience

Abstract

Background:Thrombotic thrombocytopenic purpura is a potentially life-threatening condition. Although the introduction of therapeutic plasma exchange has reduced mortality rates from over 90% to 10%-20%, approximately 40% of patients relapse, and outcomes may be fatal in refractory patients. There is clearly a need for additional therapeutic approaches.Aims:To describe the outcomes of relapsed/refractory thrombotic thrombocytopenic purpura patients treated with vincristine as an adjunct to therapeutic plasma exchange.Study Design:Cross-sectional study.Methods:The medical records of all relapsed/refractory patients with thrombotic thrombocytopenic purpura treated with vincristine adjunct to therapeutic plasma exchange between October 2000 and December 2016 were retrospectively reviewed. Diagnosis of thrombotic thrombocytopenic purpura was based on clinical history, physical examination, and laboratory examinations. Patient demographics, laboratory findings, initial date and duration of therapeutic plasma exchange, dosage and time of administration of vincristine, and outcomes were recorded.Results:The study included 15 patients [median age: 37 years (range: 26-65); 7 women and 8 men] with either relapsed or refractory thrombotic thrombocytopenic purpura who were treated with vincristine as an adjunct to therapeutic plasma exchange for a total of 22 episodes. Eighty-seven percent of patients achieved remissions in 20 of 22 episodes, with a median duration of remission of 29.5 months (range: 3-105). After a median follow-up of 55 months, 11 patients were alive. Vincristine was well tolerated with no safety concerns.Conclusion:Vincristine offers a reasonable option for the treatment of patients with relapsed/refractory thrombotic thrombocytopenic purpura. Further studies evaluating vincristine in the front-line setting and in the relapsed/refractory setting are needed to validate the role of vincristine in thrombotic thrombocytopenic purpura patients.

<p>Assessment and Monitoring of Patients with Immune-Mediated Thrombotic Thrombocytopenic Purpura (iTTP): Strategies to Improve Outcomes</p>

“…38,39 In patients with relapsed/refractory iTTP, cyclophosphamide, cyclosporine, mycophenolate, vincristine, bortezomib, N-acetylcysteine, and splenectomy can be beneficial. [40][41][42][43][44][45][46] In addition to the aforementioned treatment approaches, caution should be exercised for other potential complications of TTP treatment. Although platelet transfusion is usually contraindicated in TTP as it can lead to life-threatening thrombotic events, platelet transfusion may be required in patients with severe thrombocytopenia, who have clinically life-threatening bleeding or require urgent surgical intervention.…”

<p>Caplacizumab as an emerging treatment option for acquired thrombotic thrombocytopenic purpura</p>

“…In cases who remain refractory to PEX plus corticosteroids, the administration of high-dose methylprednisolone 1 g per day for 3 days can be the choice of treatment 5. Other treatment options in patients with relapsed/refractory TTP may include rituximab, vincristine, cyclophosphamide, cyclosporine A, and splenectomy 6–11. Rituximab was shown to be effective as a second-line therapy,12 as well as in the upfront setting as an adjunct to PEX and corticosteroids 13–15.…”