Successful eradication of acquired factor-VIII-inhibitor using single low-dose rituximab

Single-dose rituximab plus glucocorticoid versus cyclophosphamide plus glucocorticoid in patients with newly diagnosed acquired hemophilia A: A multicenter, open-label, randomized noninferiority trial

Acquired hemophilia A (AHA) is a rare but serious bleeding disorder. Randomized controlled trial (RCT) comparing the efficacy of immunosuppression therapy for AHA lacks. We conducted the first multicenter RCT aiming to establish whether the single-dose rituximab combination regimen was noninferior to the cyclophosphamide combination regimen. From 2017 to 2022, 63 patients with newly diagnosed AHA from five centers were randomly assigned 1:1 to receive glucocorticoid (methylprednisolone 0.8 mg/kg per day for the first 3 weeks and then tapered) plus single-dose rituximab (375 mg/m2 ; n = 31) or plus cyclophosphamide (2 mg/kg per day until inhibitor becomes negative, for a maximum of 5 weeks; n = 32). The primary outcome was complete remission (CR, defined as FVIII activity ≥50 IU/dL, FVIII inhibitor undetectable, immunosuppression tapered and no bleeding for 24 h without bypassing agents) rate measured within 8 weeks. The noninferiority margin was an absolute difference of 20%. Twenty-four (77.4%) patients in the rituximab group and 22 (68.8%) patients in the cyclophosphamide group achieved CR, which showed the noninferiority of the single-dose rituximab-based regimen (absolute difference = -8.67%, lower limit of the 95% confidence interval = -13.11%; Pnoninferiority = 0.005). No difference was found in the incidence of treatment-related adverse events. Single-dose rituximab plus glucocorticoid regimen showed similar efficacy and safety, without a reported risk of secondary malignancies or reproductive toxicity seen in cyclophosphamide, it might be recommended as a first-line therapy for AHA, especially in China where there is a young age trend in AHA patients. This trial was registered at ClinicalTrials.gov as #NCT03384277.

A low-dose rituximab regimen for first-line treatment of acquired haemophilia A

A low-dose rituximab regimen for first-line treatment of acquired haemophilia A.

INTRODUCTION

Acquired haemophilia A (AHA) is a rare disease caused by the development of autoantibodies against FVIII. Diagnosis involves confirmation of FVIII deficiency and the presence of an inhibitor via the Bethesda assay. Severe bleeding is often managed with bypassing agents such as recombinant factor VII. This is then followed by eradication of the inhibitor with immunosuppression which typically includes a corticosteroid backbone.

AIM

Review the current management and outcomes of AHA in Queensland, Australia. Determine the incidence, demographics and clinical characteristics of AHA patients.

METHODS

Retrospective case series of AHA diagnosed between May 2014 and August 2018. Data were derived from the Australian Bleeding Disorders Registry and state-wide pathology database. Data collection proforma was completed by the treating haematologist and reviewed/compiled centrally.

RESULTS

24 patients were identified (incidence 1 in 1.27 million). The median age was 76.5 years. Median follow-up was 20 months. Index bleed was atraumatic and skin/soft tissue in the majority of patients. Recombinant FVIIa was the most commonly used haemostatic therapy and effective in 85% of patients. Immunosuppression and steroid usage were uniform. Upfront second agent was used in 75% of patients and was most commonly rituximab. 87.5% of patients achieved a complete remission in a median time of 48 days. Low-dose rituximab was frequently used and equally as efficacious as standard dose.

CONCLUSION

Immunosuppression with combination therapy, notably rituximab, appears to be non-inferior and has a favourable side effect profile.

Rituximab for eradicating inhibitors in people with acquired haemophilia A

BACKGROUND

Acquired haemophilia A is a rare bleeding disorder caused by the development of specific autoantibodies against coagulation factor VIII. Standard treatment, usually steroids alone, or in combination with cyclophosphamide, aims to stop acute bleeds by using haemostatic agents to promote clotting. Rituximab may be an alternative approach to the treatment of acquired haemophilia by eradicating FVIII autoantibodies. This is an update of a previously published Cochrane Review.

OBJECTIVES

To assess the efficacy and adverse effects of rituximab for treating people with acquired haemophilia A.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's trials registers, comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and conference proceedings (January 2021). We also undertook searches of CENTRAL, MEDLINE and online trial registries (January 2021).

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of rituximab for people with acquired haemophilia A, with no restrictions on gender, age or ethnicity.

DATA COLLECTION AND ANALYSIS

No trials matching the selection criteria were eligible for inclusion.

MAIN RESULTS

No trials matching the selection criteria were eligible for inclusion.

AUTHORS' CONCLUSIONS

We found no randomised clinical trials of rituximab for acquired haemophilia A. Thus, we are not able to draw any conclusions or make any recommendations on rituximab for eradicating inhibitors in people with acquired haemophilia A based on the highest quality evidence. Given that undertaking randomised controlled trials in this field is a complex task, we suggest that, while planning such trials, clinicians treating the disease continue to base their choices on alternative, lower-quality sources of evidence. In a future update of this review, we plan to appraise and incorporate eligible randomised controlled trials, as well as other high-quality, non-randomised studies.

Reduced-intensity, risk factor-stratified immunosuppression for acquired hemophilia A: single-center observational study

Immunosuppressive therapy (IST) is administered to patients with acquired hemophilia A (AHA) to eradicate autoantibodies against coagulation factor VIII (FVIII). Data from registries previously demonstrated that IST is often complicated by adverse events, in particular infections. This pilot study was set out to assess the feasibility of reduced-intensity, risk factor–stratified IST. We followed a single-center consecutive cohort of twenty-five patients with AHA receiving IST according to a new institutional treatment standard. Based on results from a previous study, GTH-AH 01/2020, patients were stratified into “poor risk” (FVIII < 1 IU/dl or inhibitor ≥ 20 Bethesda units (BU)/ml) or “good risk” (FVIII ≥ 1 IU/dl and inhibitor < 20 BU/ml). Outcomes were compared between the current cohort and the GTH registry as a historic control (n = 102). Baseline characteristics of the cohort were not different from the historic control. Partial remission, defined as FVIII recovered to > 50 IU/dl, was achieved by 68% of patients after a median time of 112 days, which was lower and significantly later than in the historic control (hazard ratio: 1.8, 95% confidence interval 1.2–2.8). Complete remission, overall survival, and frequency of fatal infections were not different. Grade 3 and 4 infections were more frequent. The impact of risk factors that was observed in the historic cohort was no longer apparent, as partial and complete remission and overall survival were similar in “good risk” and “poor risk” patients. In conclusion, reduced-intensity, risk factor–stratified IST is feasible in AHA but did not decrease the risk of infections and mortality in this cohort.

International recommendations on the diagnosis and treatment of acquired hemophilia A

Acquired hemophilia A (AHA), a rare bleeding disorder caused by neutralizing autoantibodies against coagulation factor VIII (FVIII), occurs in both men and women without a previous history of bleeding. Patients typically present with an isolated prolonged activated partial thromboplastin time due to FVIII deficiency. Neutralizing antibodies (inhibitors) are detected using the Nijmegen-modified Bethesda assay. Approximately 10% of patients do not present with bleeding and, therefore, a prolonged activated partial thromboplastin time should never be ignored prior to invasive procedures. Control of acute bleeding and prevention of injuries that may provoke bleeding are top priorities in patients with AHA. We recommend treatment with bypassing agents, including recombinant activated factor VII, activated prothrombin complex concentrate, or recombinant porcine FVIII in bleeding patients. Autoantibody eradication can be achieved with immunosuppressive therapy, including corticosteroids, cyclophosphamide and rituximab, or combinations thereof. The median time to remission is 5 weeks, with considerable interindividual variation. FVIII activity at presentation, inhibitor titer and autoantibody isotype are prognostic markers for remission and survival. Comparative clinical studies to support treatment recommendations for AHA do not exist; therefore, we provide practical consensus guidance based on recent registry findings and the authors' clinical experience in treating patients with AHA.

Rituximab for eradicating inhibitors in people with acquired haemophilia A

BACKGROUND

Acquired haemophilia A is a rare bleeding disorder caused by the development of specific autoantibodies against coagulation factor VIII. Rituximab may be an alternative approach to the treatment of acquired haemophilia by eradicating FVIII autoantibodies.

OBJECTIVES

To assess and summarise the efficacy and adverse effects of rituximab for treating people with acquired haemophilia A.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's trials registers, comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and conference proceedings.Date of last search of the Cochrane Cystic Fibrosis and Genetic Disorders Group's trials registers: 01 March 2016.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of rituximab for people with acquired hemophilia A, with no restrictions on gender, age or ethnicity.

DATA COLLECTION AND ANALYSIS

No trials matching the selection criteria were eligible for inclusion.

MAIN RESULTS

No trials matching the selection criteria were eligible for inclusion.

AUTHORS' CONCLUSIONS

No randomised clinical trials of rituximab for acquired hemophilia A were found. Thus, based on the highest quality of evidence, we are not able to draw any conclusions or make any recommendations on rituximab for eradicating inhibitors in people with acquired haemophilia A. Given that undertaking randomised controlled trials in this field is a complex task, the authors suggest that, while planning such trials, clinicians treating the disease continue to base their choices on alternative, lower quality sources of evidence. The authors plan, for a future update of this review, to appraise and incorporate any randomised controlled trials, as well as other high-quality non-randomised studies.

The anti-CD20 monoclonal antibody rituximab to treat acquired haemophilia A

BACKGROUND

Acquired haemophilia A (AHA) is a rare bleeding disorder caused by the development of specific autoantibodies against naturally occurring factor VIII (FVIII). Although about half of cases are idiopathic, AHA may be associated with several non-neoplastic conditions, autoimmune disorders, as well as haematological malignancies, such as chronic lymphocytic leukaemia and lymphoma. The long-term suppression of inhibitors is one of the mainstays of the treatment of AHA. Apart from standard immunosuppressive treatments, rituximab has been proven to be effective in AHA.

MATERIALS AND METHODS

The aim of this review is to provide a systematic description of data available in the literature on this topic. To do so, we performed a search using the indexed online database Medline/PubMed, without temporal limits, matching the words "rituximab" and "acquired h(a)emophilia". Furthermore, additional published studies were identified in the reference list of the publications found in PubMed.

RESULTS

The review of the literature confirms that rituximab may be a safe and useful treatment for AHA.

DISCUSSION

Although rituximab is not a standard therapy for AHA, it may be useful in resistant cases. However, the definitive place of this monoclonal antibody in the therapeutic strategy for AHA (first or second-line, alone or in combination with other drugs) remains to be determined more precisely and warrants further investigation.

Acquired hemophilia in the patient suffering from rheumatoid arthritis: case report

Acquired hemophilia is a severe bleeding diathesis caused by autoantibodies against a coagulation factor VIII (FVIII inhibitor). Massive bleeding diathesis, often life threatening are observed in almost 90% of patients. In 50-60% of cases, inhibitor emerges spontaneously. However, there are some conditions like pregnancy, puerperium, autoimmune disorders or cancers that seem to induce acquired hemophilia. We report a case of a 49-year-old woman suffering from rheumatoid arthritis (RA) for several years, who was diagnosed with acquired hemophilia in September 2011. The patient had been treated by steroids and leflunomide during the last few months. At the time of diagnosis, diffuse bruising of the forearms and the trunk was observed. The patient was treated with recombinant activated factor VII, and the first-line immunosuppressive therapy was introduced (cyclophosphamide and prednisone). We observed the elimination of symptoms and the disappearance of diathesis. Significant reduction of the titer of inhibitor was achieved, but only partial remission was obtained. It lasted until the beginning of December 2011, when the titer of the inhibitor increased again and massive bleeding to the left lower limb occurred. It was necessary to administer recombinant factor VIIa together with the second-line immunosuppressive therapy based on the Budapest protocol. The rapid reduction of the diathesis and improvement of the patient's general condition was achieved as previously. However, still there was no complete remission. After 2 weeks of treatment, the titer of inhibitor diminished, and factor VIII activity increased slightly. Because of RA, the patient was treated with methylprednisolone in maintenance doses during the next few weeks. Unfortunately, after over a month, the increase of inhibitor titer and the decrease of FVIII level were observed again. Some bruises appeared. It was necessary to increase doses of corticosteroids to therapeutic levels and add cyclophosphamide in low doses to prevent the appearance of more hemorrhagic diathesis. Partial remission was achieved a second time at the end of April 2012. The patient was given methylprednisolone with chloroquine as a maintenance treatment and the control of RA. The titer of the inhibitor increased again in June 2012, but there were no signs of diathesis. In August 2012, some bruises were detected, and we decided to add cyclophosphamide again instead of escalating the doses of methylprednisolone to prevent the occurrence of side-effects of corticosteroids. Cyclophosphamide was given with intervals only depending on activated partial thromboplastin time. No further diathesis was observed in spite of the lack of remission. We were forced to withdrawn cyclophosphamide completely in October 2012 because of signs of hematuria. Fortunately, right nephrolithiasis and urinary tract infection were the cause of that condition. These symptoms vanished after standard supportive treatment. Maintenance doses of corticosteroids and chloroquine were continued as the main treatment. The patient's condition was good, but the titer of inhibitor increased over the value that had been detected at the time of diagnosis, and some bruises appeared again at the end of January 2013. The decision to use rituximab as the next-line therapy was made. This anti-CD20 monoclonal antibody is primarily used in the management of lymphomas. However, it has been successfully applied in the management of various autoimmune conditions. The usual treatment regime involves four separate intravenous infusions of 375 mg/m each, administered at weekly intervals. At the time of admission to the hospital in the second half of February 2013, the titer of inhibitor was dangerously high, almost three times more than the initial level. Fortunately, only a few bruises were observed, and no bypassing agents were needed. The patient was given the whole-planned therapy. Concomitant continuation of maintenance doses of corticosteroids was necessary to enforce the effect of eradication of inhibitor because of high levels of its titer during rituximab administration. It prevented the patient from massive diathesis that might occur. The laboratory tests were improving during the next subsequent weeks after the last dose of rituximab. Over a month later, a significant decrease of the titer of inhibitor and an increase of factor VIII activity was observed. Probably, the laboratory tests will be improving during the next few weeks. The patient is in outpatient care now. She is treated with maintenance doses of corticosteroids and chloroquine as the main treatment of RA. We will try to withdraw corticosteroids unless it is not feasible to achieve complete remission. We will have to introduce another kind of immunosuppressive agent in case of recurrence.

Acquired Factor VIII Inhibitor: A Rare Etiology for Bruisability and Anemia

Acquired factor VIII inhibitor is a very rare cause of easy bruisability, muscular hematomas, and subsequent anemia in the elderly patient population. The incidence of acquired factor VIII inhibitor is one in one million. Here we report an elderly patient who presented to the hospital for bruising easily fatigue and was found to have acquired factor VIII inhibitor on further investigation. He responded to the treatment appropriately, and hemostasis was achieved successfully with recombinant VII concentrates and eradication of the inhibitor with Imuran and steroid combination.

A Case of an Acquired Factor VIII Inhibitor Complicated by Multiple Treatment-Related Opportunistic Infections and Review of the Literature

This case report describes a patient with an idiopathic acquired Factor VIII inhibitor and severe bleeding. She was treated with rituximab after failing first-line treatment with steroids and cyclophosphamide. Two months following rituximab treatment, our patient developed a succession of severe opportunistic infections requiring intensive care unit admission. Over a period of 12 weeks she required treatment for Pseudomonas aeruginosa septicaemia, herpes simplex gingivostomatitis and pharyngotonsillitis, clostridium difficile-related diarrhoea, systemic cytomegalovirus infection, pneumocystis jiroveci, and invasive pulmonary aspergillosis lung infections. After significant rehabilitation, the patient was finally discharged following a 5-month admission. This case highlights the complexity of balancing a life-threatening condition with the side effects of treatment. It also raises the issue of routine prophylaxis for immunosuppression in nonmalignant conditions, which will become a common dilemma with the expanding indications for rituximab use.

A single dose of rituximab does not deplete B cells in secondary lymphoid organs but alters phenotype and function

A single dose of the anti-CD20 monoclonal antibody rituximab induces a nearly complete B cell depletion in peripheral blood, but not in secondary lymphoid organs. Modulation of this remaining B cell population due to rituximab treatment may contribute to the therapeutic effects of rituximab. To assess the in vivo effects of rituximab we used lymph nodes (LNs) collected during renal transplant surgery in patients who had received rituximab 4 weeks earlier in preparation for an ABO-incompatible transplantation. Rituximab treatment resulted in a lower percentage of naïve (IgD(+)CD27(-)) and a higher percentage of switched memory (IgD(-)CD27(+)) B cells. Remarkably, transitional (CD24(++)CD38(++)) B cells were virtually lacking in the LNs of rituximab-treated patients. Moreover, LN-derived B cells from rituximab-treated patients produced different amounts of various Ig-subclasses after anti-CD40/IL-21 stimulation ex vivo. Finally, after stimulation of allogeneic T cells with LN-derived B cells from rituximab-treated patients, the proliferated T cells showed a decreased production of IL-17. In conclusion, after treatment with rituximab there remains a B cell population with different functional capacities. Consequently, the effect of rituximab on the immune response will not only be determined by the extent of B cell depletion, but also by the functional properties of the remaining B cells.

The use of monoclonal antibodies in immune-mediated hematologic disorders

In this article, the evidence on the clinical use of monoclonal antibodies in the treatment of immune-mediated hematologic disorders is described. Insights into pathogenic mechanisms have revealed a major role of both B and T cells. Controlled trials have shown conflicting results, necessitating further research regarding pathogenesis, mechanism of action, and resistance. Although the use of more potent and specific monoclonal antibody therapy, mainly targeting costimulation signals, may improve response rates and long-term outcome, its use should be carefully balanced against potential side effects.

Rituximab therapy for autoimmune haematological diseases

Autoimmune haematological diseases are characterized by the production of antibodies against blood proteins or cells, and comprise primary immune thrombocytopenia, autoimmune haemolytic anaemia, acquired haemophilia, and thrombotic thrombocytopenic purpura. Current treatments for these disorders include corticosteroids, cytotoxic drugs and splenectomy, which may be associated with significant systemic toxicity and/or morbility. B cells play a key role in both the development and perpetuation of autoimmunity, since they produce autoantibodies but also function as antigen-presenting cells, and release immunomodulatory cytokines. Rituximab, an anti-CD20 monoclonal antibody that specifically depletes B cells, may be an effective treatment strategy for patients with autoimmune disorders. This article reviews data of the literature, showing that patients with autoimmune haematological diseases can respond to rituximab irrespective of age and number or type of prior treatments. These data suggest that rituximab provides an effective and well-tolerated treatment option for these conditions.

Anti-CD20 monoclonal antibodies and their use in adult autoimmune hematological disorders

Autoimmune hematological disorders encompass a broad group of hematological conditions characterized by the loss of self-tolerance to a variety of antigens. Despite good response to first-line therapy in the majority of patients, relapses are common, necessitating new and safe therapeutic options. The anti-CD20 monoclonal antibody rituximab has led to substantial improvement in the treatment of malignant and immune-mediated disorders involving B cells. Although experience with rituximab in immune-mediated hematological disorders is rarely supported by randomized trials, there is now substantial experience with rituximab suggesting that anti-CD20 therapy is an effective and well-tolerated alternative to immunosuppressive therapy in these disorders. However, caution is needed based on recent reports describing-sometimes severe-rituximab-related complications.