Rapid improvement of thrombotic thrombocytopenic purpura with vincristine and plasmapheresis

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

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.

Mycophenolate mofetil in a case of relapsed, refractory thrombotic thrombocytopenic purpura

A case of relapsing and refractory thrombotic thrombocytopenic purpura received mycophenolate mofetil (MMF) to attempt to maintain remission. The possible use of MMF in thrombotic thrombocytopenic purpura is discussed.

Thrombotic Thrombocytopenic Purpura: aetiology, pathophysiology and treatment

Thrombotic thrombocytopenic purpura (TTP) is a rare disorder whose varied clinical manifestations result from the formation of platelet-rich thrombi within the microvasculature and consequent tissue ischaemia. This review will outline how, in the eighty years since its initial description, scientific discoveries have not only led to a deeper understanding of the fundamental pathophysiology of TTP, but have also contributed to advances in the clinical management of this condition. Current research in this field will hopefully provide the basis for the design and development of novel therapeutic strategies.

Immunotherapy for thrombotic thrombocytopenic purpura

PURPOSE OF REVIEW

This review focuses on recent advances in the use of immune-based therapy to treat patients with refractory and relapsing acquired thrombotic thrombocytopenic purpura.

RECENT FINDINGS

Advances in understanding of the pathophysiology of idiopathic thrombotic thrombocytopenic purpura have provided the rationale for immune-based treatment approaches to refractory and relapsing cases of thrombotic thrombocytopenic purpura. The demonstration that a severe deficiency of von Willebrand factor-cleaving protease activity in acquired thrombotic thrombocytopenic purpura is due to an autoantibody inhibitor of the von Willebrand factor-cleaving protease argues for targeting the antibody inhibitor of the von Willebrand factor-cleaving protease with immunosuppressive therapy as a means of increasing protease activity and inducing a sustained remission of the disease. Recent publications, largely case reports and small series of patients, have suggested a role for rituximab and cyclosporine in cases refractory to plasma exchange or resistant to the tapering of plasma exchange therapy.

SUMMARY

In the future, a better understanding of the relation between the von Willebrand factor-cleaving protease activity, the nature and titer of von Willebrand factor-cleaving protease inhibitors, and the risk of relapse of thrombotic thrombocytopenic purpura will be important to further validate the strategy of targeting the von Willebrand factor-cleaving protease inhibitory antibody as an effective means of treating acquired thrombotic thrombocytopenic purpura. Prospective data from carefully designed clinical trials are needed to define the effectiveness of specific immunosuppressive therapies at suppressing antibody inhibitors of von Willebrand factor-cleaving protease, improving von Willebrand factor-cleaving protease activity, and inducing a sustained remission of the disease.

Combination vincristine and plasma exchange as initial therapy in patients with thrombotic thrombocytopenic purpura: one institution's experience and review of the literature

BACKGROUND

Thrombotic thrombocytopenic purpura (TTP) was once a highly fatal disease with mortality reaching nearly 95 percent; however, application of therapeutic plasma exchange (TPE) has dramatically increased survival. Nevertheless, mortality remains substantial (10%-30% in many published reports), requiring the search for more efficacious treatments. Vincristine (VCR) has been generally reserved for refractory TTP. Despite its effectiveness in a salvage mode, VCR has not been widely advocated as first-line therapy in conjunction with TPE. We previously reported improved survival when VCR and TPE were administered at presentation in patients treated from 1979 to 1994. Utilizing this standardized approach, outcomes of an additional group of patients and the results of a literature review of VCR therapy for TTP are reported.

STUDY DESIGN AND METHODS

Medical records of all patients with a diagnosis of TTP treated between 1995 and 2002 at Cedars-Sinai Medical Center were reviewed. TPE was performed daily, exchanging 1.25 plasma volumes, until the platelet count normalized. Patients received VCR 1.4 mg/m2, (up to 2.0 mg total dose) after the first TPE. A literature review of all publications utilizing VCR in the management of TTP was performed with MEDLINE.

RESULTS

Twelve consecutive patients meeting the diagnostic criteria received treatment with VCR and TPE. All patients achieved durable remission. Patients tolerated VCR without significant complications.

CONCLUSION

Our 100 percent survival rate, as well as evidence garnered from the literature review, suggests that combination therapy with VCR and TPE at presentation might be more effective than TPE alone and therefore warrants consideration as first-line therapy for TTP patients.

Use of vincristine and cyclosporine in childhood thrombotic thrombocytopenic purpura

Thrombotic thrombocytopenic purpura (TTP) is a rare but life-threatening hematologic disorder in children. Plasmapheresis, the standard therapy for TTP, is effective in achieving remission in most patients. However, some patients become either refractory to or dependent upon plasmapheresis. The authors report three such patients in whom the use of vincristine or vincristine plus cyclosporine resulted in permanent remission. A 12-year-old girl with TTP dependent on plasmapheresis for more than 5 months responded to vincristine with a decrease in the required frequency of plasmapheresis, but the addition of cyclosporine abrogated the need for further plasmapheresis. She subsequently developed serologic evidence of systemic lupus erythematosus. Two 15-year-old boys with TTP (one of them with underlying mixed connective tissue disease) became refractory to plasmapheresis after a brief initial response. The addition of vincristine in one patient and vincristine and cyclosporine in the second (with mixed connective tissue disease) led to complete remission. The authors' experience in this case study of three patients suggests that vincristine and cyclosporine are effective agents in the management of patients with TTP who do not achieve complete remission with plasmapheresis alone.

Difficulties in the management of an incomplete form of refractory thrombotic thrombocytopenic purpura, the usefulness of vincristine

BACKGROUND

Although several etiologies can be identified in thrombotic thrombocytopenic purpura (TTP), idiopathic cases are still frequent. Incomplete forms are more rare. Currently, the diagnosis may be made in cases of thrombocytopenia and microangiopathic hemolytic anemia. According to the literature, mortality and morbidity are significantly improved with plasma exchange. However, treatment in refractory forms remains problematic.

CASE REPORT

A 33-year old woman presented with an incomplete form of TTP, refractory to a combination of therapeutics. The patient underwent plasma infusion, plasma exchange, and then was started on corticosteroids. She also received intravenous immunoglobulins and antiplatelet agents in close proximity to vincristine (Oncovin) infusion. The main biological indicators used were the platelet count, hematocrit, LDH, and the presence of schistocytes. Following vincristine treatment, the patient's condition rapidly improved.

CONCLUSION

Vincristine administered after the failure of standard therapeutics was effective in this refractory form of TTP.

[Idiopathic thrombotic thrombocytopenic purpura or Moschowitz syndrome: current physiopathologic and therapeutic perspectives]

INTRODUCTION

The objective of this work was to review current data about the physiopathology, clinical features, and treatment of thrombotic thrombocytopenic purpura (Moschowitz's syndrome).

CURRENT KNOWLEDGE AND KEY POINTS

Thrombotic thrombocytopenic purpura is a rare disorder characterized by widespread thrombotic injuries of platelets in the microcirculation. Its physiopathology has been elucidated recently. Evidence of a deficiency of Von Willebrand's factor-cleaving protease would be due to either IgG antibodies in the acute form of the disease or constitutional deficiency in the chronic form of the disease.

FUTURE PROSPECTS AND PROJECTS

Plasma exchange is the current reference treatment. However, in the light of recent publications, either infusions of concentrates of purified enzyme or more intensive immunosuppressive therapy would be more specific.

Improved survival with plasma exchange in patients with thrombotic thrombocytopenic purpura-hemolytic uremic syndrome

PURPOSE

Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome are uncommon disorders that are generally fatal if left untreated. Plasma exchange therapy is associated with high response rates and improved short-term survival, but most previous studies have been limited by small numbers of patients or short duration of follow-up.

METHODS

We performed a retrospective cohort analysis in 126 consecutive patients with thrombotic thrombocytopenic purpura/hemolytic uremic syndrome, most of whom were treated principally with plasma exchange at the Sacramento Medical Foundation Blood (Center and the University of California Davis Medical Center between 1978 and 1998. We measured the effect of therapeutic plasma exchange on 30-day mortality, response rate, and overall survival, and determined which factors were associated with 30-day mortality and relapse.

RESULTS

The overall 30-day mortality was 10% of the 122 patients who received plasma exchange as their principal treatment (a median of 9 exchanges and a mean cumulative infused volume of 43 +/- 77 L fresh frozen plasma); 56% were complete responders and 21% were partial responders. The relapse rate was 13%. The estimated 2-year survival was about 60%; among patients without serious underlying comorbid conditions, the estimated 2-year survival was about 80%. Each unit increase in clinical severity score (on a 0 to 8 scale) was associated with a 2.2-fold (95% confidence interval [CI]: 1.3 to 3.9) increase in the odds of 30-day mortality. Patients who were febrile at presentation were substantially less likely to suffer a relapse (odds ratio = 0.2; 95% CI: 0.03 to 0.9).

CONCLUSION

Plasma exchange therapy produced high response and survival rates in this large cohort of patients with thrombotic thrombocytopenic purpura/hemolytic uremic syndrome. The Clinical Severity Score may be useful in predicting 30-day mortality, whereas fever at onset was associated with a lesser risk of relapse. Prospective studies should stratify patients according to these prognostic factors.

Current Clinical Practice: Current Management of Thrombotic Thrombocytopenic Purpura

Historically, the mortality rate of thrombotic thrombocytopenic purpura (TTP) approached 100%. However, by the 1980's, new therapy was instituted with a vast improvement in survival to 90%. The exact pathogenesis of TTP remains elusive. Yet, despite incomplete understanding of the pathophysiology, outcome has improved due to increased awareness of the symptomatology leading to earlier diagnosis and better supportive care, in addition to effective therapy with plasma exchange. TTP represents a disease in which prompt diagnosis and treatment can lead to a critical difference in clinical outcome.

Thrombotic thrombocytopenic purpura: diagnosis, pathogenesis and modern therapy

Thrombotic thrombocytopenic purpura (TTP) is an uncommon multisystem disorder, sometimes associated with predisposing conditions such as pregnancy, cancer, exposure to certain drugs, bone marrow transplantation and HIV-1 infection. An abnormal interaction between the vascular endothelium and platelets which occurs in certain organs leads to thrombosis, endothelial proliferation, minimal inflammation and micro-angiopathic haemolysis. Recent studies suggest that endothelial cell perturbation and apoptosis caused by an as yet unknown plasma factor(s) may lead to the release of abnormal von Willebrand factor which facilitates the deposition of platelet microthrombi. Exchange transfusions of plasma or plasma-cryosupernatant remain the cornerstone of the treatment of TTP along with corticosteroids, platelet inhibitor drugs, vincristine and splenectomy. In most cases remissions can be attained, and cures are now common-although approximately one-half of the patients will relapse. While relapses are usually milder, they still carry a significant mortality and preventive therapies are not always effective.

Treatment of plasma refractory thrombotic thrombocytopenic purpura with protein A immunoabsorption

The objective of this study was to assess the effect of protein A immunoabsorption in terms of response rate and toxicities in patients with classical thrombotic thrombocytopenic purpura (TTP) refractory to therapeutic plasma exchange. The study included nine females and one male with a diagnosis of classical TTP treated at multiple university hospital centers with protein A immunoabsorption (PAI) after having failed plasma exchange. The 10 patients had an age range 17-62 years. Prior to PAI, the patients had failed to respond to a mean of 15 (range 6-39) therapeutic plasma exchanges. Three patients had previous episodes of TTP. Evaluation for response to PAI included serial measurements of serum creatinine, lactate dehydrogenase (LDH), hemoglobin, hematocrit, and platelet count before, during, and up to 18 months post-PAI treatment. Seven of 10 study patients had resolution of their TTP. Six of the patients required six or fewer therapeutic PAIs and one required 12 treatments. All responding patients had evidence of improvement by the third PAI treatment. Three patients demonstrated no response to PAI, with two patients expiring from complications of TTP and one patient demonstrating a complete response to a subsequent therapy. No significant toxicity was noted with the use of PAI in this setting. Protein A immunoabsorption in patients with classical TTP refractory to plasma exchange can produce durable complete remissions and warrants comparative studies.

Thrombotic thrombocytopenic purpura: early and late responders

Thrombotic thrombocytopenic purpura (TTP) is characterized by micro-angiopathic hemolytic anemia (MAHA), thrombocytopenia, neurological symptoms, renal involvement, and fever. We describe our experience in 70 serially encountered TTP patients in the last decade who were treated with a standard therapeutic plasma exchange (TPE) protocol. Seventy percent of the patients were females. The median age of the patients was 43 years (range: 8-80). Sixty patients (85.7%) had a complete response to TPE therapy. This represented 91% of 66 who received at least one TPE. Ten patients died, two patients died before and two during the first plasma exchange. The median number of TPEs performed was nine (range: 1-85). Thirty-five (58%) out of 60 responded to 3-9 TPEs, and 25 (42%) required 10-34 TPEs for the response. The median total plasma volume exchanged was 28 liters (range: 2.7-250 L) and the mean plasma volumes exchanged during each procedure was 3.2 (SD +/- 1.09 L). The patients were classified into early responders (ER) and late responders (LR). ERs had a mean platelet count of 180 x 10(9)/L by Day 5, mean LDH of 643 IU/L by Day 7, and required median of seven TPEs. LRs had a mean platelet count of 122 x 10(9)/L by Day 5, mean LDH of 885 IU/L by Day 7, and required median of 19 TPEs (P = 0.001). The platelet counts were significantly higher (P = 0.01-0.03) in ERs on Days 1, 3, and 5 as compared to LRs but the LDH did not differ significantly. Seventy-seven percent of LRs had exacerbation of TTP and 18% had relapse as compared to 7% each in ERs. Thirteen patients were in coma/semicoma at presentation. Out of these, six died, making coma a bad prognostic indicator. Five of the seven survivors in coma had received two single-plasma volume exchanges on Day 1. In conclusion, 91% of TTP patients had an excellent response to plasma exchange therapy with FFR Coma/ semicoma appears to be a bad prognostic indicator. LRs needed prolonged treatment with a greater number of patients experiencing exacerbation and relapse of TTP as compared to ERs.

Influence of type of exchange fluid on survival in therapeutic apheresis for thrombotic thrombocytopenic purpura

Thrombotic thrombocytopenic purpura (TTP) is a potentially lethal disease that may respond favorably to plasma infusion or therapeutic plasma exchange (TPE) with frozen plasma (FP) as the exchange fluid. Frozen plasma from which the cryo-precipitated fraction has been removed (cryopoor plasma, CP) has reportedly been useful in refractory cases in which a response to FP is not being observed. We report a retrospective analysis of all cases of TTP treated by TPE with either FP (1985-1989) or CP (1989-1993) as exchange fluid at a large tertiary care hospital between the years 1985 and 1993. A severity score index was compiled for each patient using the platelet count, mental status, hematocrit, and renal function at the time of diagnosis. Nineteen patients were treated with FP (group 1) and 18 patients with CP (group 2). Groups did not differ in age, gender, race, hematologic parameters, or severity scores. Patients treated with CP, however, had more plasma exchange (14 +/- 10 vs. 12 +/- 8, respectively) and more fluid exchanged than these treated with FP (50 L +/- 36 vs. 37 L +/- 40, respectively). Survival was 72% in the CP group and 47% in the FP group. Although a survival advantage for the use of CP as exchange fluid in the treatment of TTP is suggested by our observations, the retrospective nature of the study, lack of randomization, and sequential rather than concurrent use of FP and CP indicates caution in interpretation. The data do indicate, however, that use of CP is acceptable as the initial exchange fluid in TTP.

Serum lactate dehydrogenase and platelet count predict survival in thrombotic thrombocytopenic purpura

A significant number (some 20%) of patients with thrombotic thrombocytopenic purpura do not respond to standard therapy and die. We reasoned that early identification of those who are likely to fail standard therapy would allow the rational introduction of other treatment modalities. To this end we prospectively evaluated 27 consecutive patients, examining serum LDH levels and platelet counts as markers of disease activity and as predictors of outcome. All patients were treated, according to a written protocol, with high volume plasma exchange (35 ml/kg), prednisone, aspirin, and persantine. Twenty-one of the 27 patients (78%) are alive following therapy. Initial LDH and platelet values did not distinguish between the survivors and nonsurvivors. However, by day 3 of therapy both LDH levels and platelet counts differed significantly between the two groups. Mean day 3 LDH level for survivors was 364 units/L, and for nonsurvivors, 891 units/L (P < 0.005). Mean day 3 platelet count for survivors was 119,000/microL, and for nonsurvivors, 46,000/microL (P < 0.005). Receiver Operator Characteristic curves were constructed and assessed by calculating the area under the curve. This analysis showed that LDH is able to discriminate survivorship one day earlier than platelet count. Both LDH level and platelet count are excellent predictors of survival, under standard therapy, after 3 days of treatment. Early identification of those at greatest risk will facilitate the early institution and evaluation of alternative methods of treatment, such as splenectomy, intravenous Ig, or Vincristine.

Successful treatment of recurrent thrombotic thrombocytopenic purpura with plasmapheresis and vincristine

An adolescent girl with severe thrombotic thrombocytopenic purpura (TTP) remained in a critical condition after 3 weeks of combined treatment with antiplatelet drugs, plasma infusions and plasma exchange. The introduction of vincristine resulted in gradual improvement and eventual complete remission which lasted for 2 years. When she relapsed, immediate improvement was observed with the combined treatment of plasmapheresis and vincristine. She has now been in complete remission again for 10 months. It is suggested that plasmapheresis plus vincristine should be used as the initial treatment for children with TTP.

The changing course of thrombotic thrombocytopenic purpura and modern therapy

Thrombotic thrombocytopenic purpura (TTP) is a multisystem disorder of unknown etiology. Pathologically, there appears to be an abnormal interaction between the vascular endothelium and platelets, but the primary event remains uncertain. While historically, TTP was a fatal disease, dramatic improvement in its outcome has occurred over the past two decades with the development of effective therapy. Plasma infusion or exchange remains the cornerstone of the treatment of TTP, along with corticosteroids, platelet inhibitor drugs, vincristine and splenectomy. This review summarizes the clinical findings, what is known of the pathogenesis and the available therapeutic modalities for TTP. In most cases, remissions can be attained and cures are now common. However, approximately half the patients will relapse. The clinical course at relapse is usually milder than the disease at presentation and less aggressive therapy may be needed. However, relapsing TTP still carries a significant mortality and preventive therapies are not always effective. Further progress may have to await an understanding of the fundamental etiology of this disease.

Vincristine therapy for thrombotic thrombocytopenic purpura

Thrombotic thrombocytopenic purpura (TTP) is a rare disorder characterized by microangiopathic haemolytic anemia, consumption thrombocytopenia, renal impairment, neurological dysfunction, and fever, but all these features are not present in every patient. Although the prognosis of TTP has improved since it was demonstrated that large volumes of fresh frozen plasma (FFP) lead to a remission in most patients, the disease remains fatal in many instances. Therefore, other therapies are often used in TTP, but there is skepticism about their value, since such treatments are often used in combination, making evaluation difficult. This report describes three patients with TTP and a consistent therapeutic response occurring 5 days after vincristine in each of four instances.

The clinical pharmacology and use of antimicrotubule agents in cancer chemotherapeutics

Although there has been a rapid expansion of the number of classes of compounds with antineoplastic activity, few have played a more vital role in the curative and palliative treatment of cancers than the antimicrotubule agents. Although the vinca alkaloids have been the only subclass of antimicrotubule agents that have had broad experimental and clinical applications in oncologic therapeutics over the last several decades, the taxanes, led by the prototypic agent taxol, are emerging as another very active class of antimicrotubule agents. After briefly reviewing the mechanisms of antineoplastic action and resistance, this article comprehensively reviews the clinical pharmacology, therapeutic applications, and clinical toxicities of selected antimicrotubule agents.