RARE DISEASE
Acquired hemophilia A
Acquired hemophilia A
Acquired hemophilia A
Synonyms: AHA, Acquired F8 deficiency, Acquired factor VIII deficiency
Synonyms: AHA, Acquired F8 deficiency, Acquired factor VIII deficiency
Synonyms: AHA, Acquired F8 deficiency, Acquired factor VIII deficiency
Drug discovery
0
drugs
With orphan designations
Overview
Acquired Hemophilia A (AHA) is a rare bleeding disorder caused by autoantibodies against factor VIII, leading to impaired coagulation. It presents with spontaneous mucocutaneous or soft-tissue bleeding, often in older adults without prior bleeding history. Diagnosis requires confirmation of factor VIII deficiency and inhibitor detection via Bethesda assay. Management prioritizes bleeding control with bypassing agents (e.g., recombinant FVIIa, aPCC) or recombinant porcine FVIII, followed by immunosuppressive therapy (corticosteroids ± cyclophosphamide/rituximab) for inhibitor eradication [1][2][3][6][12].
Burden
Mortality: Up to 21%, with bleeding complications (3-9%) and immunosuppression-related infections (14%) as leading causes [6][9].
Delayed diagnosis increases morbidity; treatment costs are substantial (e.g., $6M per hospitalization for rpFVIII) [6][14].
Comorbidities (e.g., cardiovascular disease) complicate management in elderly patients [6][12].
Therapies
Hemostasis: Bypassing agents (rFVIIa, aPCC) or recombinant porcine FVIII for acute bleeding; emicizumab considered in refractory cases or contraindications to traditional therapies [1][3][6][12].
Immunosuppression: First-line: corticosteroids ± cyclophosphamide; second-line: rituximab. Remission achieved in ~79% within months [1][3][6][8].
Categories: rare hematological diseases
Research Papers
888 drug discovery papers about Acquired hemophilia A, with 3 first-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
888 drug discovery papers about Acquired hemophilia A, with 3 first-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
2026-08-17 | Acquired haemophilia A associated with prostate cancer managed with recombinant activated factor VII and emicizumab.
Acquired haemophilia A (AHA) is a rare autoimmune bleeding disorder caused by neutralising antibodies against factor VIII. We describe an older man with prostate cancer on active surveillance who presented with spontaneous ecchymoses, progressive anaemia and isolated prolongation of activated partial thromboplastin time. Factor VIII activity was severely reduced, and mixing studies and Bethesda assay confirmed a high-titre factor VIII inhibitor. He achieved initial haemostatic control with recombinant-activated factor VII and was transitioned to emicizumab using an accelerated AHA regimen. No corticosteroids were given inpatient. Emicizumab was used for haemostatic prophylaxis while outpatient once-weekly rituximab was planned for inhibitor eradication. This case highlights early recognition, evaluation for associated malignancy and use of emicizumab as prophylaxis that may allow individualised immunosuppression in selected older patients.
2026-08-12 | Successful management of acquired hemophilia A with life-threatening bleeding and MRSA bacteremia in a hemodialysis patient: importance of a multimodal approach
Abstract Background Acquired hemophilia A (AHA) is a rare and fatal bleeding disorder. AHA in patients undergoing hemodialysis (HD) often leads to impaired hemostasis, necessitating temporary catheters that increase the risk of catheter-related infection. This complication hinders the use of immunosuppressive therapy, often resulting in treatment failure. We herein report the case of AHA in a patient undergoing HD with life-threatening bleeding and MRSA bacteremia, which was successfully managed with a multimodal approach. Case presentation A 64-year-old Japanese man had undergone HD owing to diabetic nephropathy and was admitted to our hospital with a massive hematoma in the left iliopsoas muscle and poor hemostasis at the vascular access site. Hemoglobin (Hb) had dropped to 5.0 g/dL despite daily blood transfusions, and activated partial thromboplastin time was alone prolonged around 60.0 s. Transcatheter arterial embolization (TAE) was performed owing to difficulty in hemostasis. After the diagnosis of AHA was made, 60 mg/day of prednisolone and bypassing agents were introduced. Additional plasma exchange (PE) was performed and rituximab was also administered. Factor VIII (FVIII) inhibitor decreased from 91.0 to 32.0 Bethesda Units (B.U)/mL, and hemostasis was achieved temporarily. Despite a decreasing trend, the FVIII inhibitor titer persisted at a high range. Hb decreased to 5.7 g/dL, and blood transfusions were needed again. Thus, a second TAE and a third PE were performed. After that, FVIII inhibitor improved to 7.0 B.U/mL, and hemostasis was fully achieved. Notably, a temporary dialysis catheter led to methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, necessitating careful PSL tapering. At 6 months after discharge, the patient had not experienced any relapse. Conclusions AHA in patients undergoing HD often leads to difficulty in hemostasis during HD, necessitating temporary catheters that almost induce catheter-related infection. This complication hinders the use of immunosuppressive therapy, sometimes resulting in treatment failure. Given the specific clinical setting of AHA in patients undergoing HD, achieving rapid bleeding control and preparing for impending infections are paramount, which necessitates a well-designed multimodal approach including immunosuppressive therapy and PP (plasmapheresis). This instructive case offers a potential framework for managing similar high-risk patients.
2026-07-17 | Acquired hemophilia a induced by clopidogrel
Introduction . Dual antiplatelet therapy (DATT) with aspirin and a platelet P2Y12 receptor inhibitor is one of the main components of treatment and secondary prevention in patients undergoing percutaneous coronary intervention in acute myocardial infarction. Among the side effects of DATT are hemorrhagic complications caused by the antiplatelet effect of the drugs. Less is known about hemorrhagic complications caused by coagulation disorders when taking clopidogrel. Aim : to present a clinical case of acquired hemophilia A, which occurred in a patient as a result of taking clopidogrel. Main findings . A 68-year-old patient received clopidogrel as part of DATT after percutaneous coronary intervention. One month later, he developed a pronounced hemorrhagic syndrome caused by the appearance of antibodies to coagulation factor VIII (FVIII:C 1.5 %, factor VIII inhibitor 61 BU). The elimination of clopidogrel, hemostatic therapy with eptacog alpha (activated) and immunosuppressive therapy with prednisone, cyclophosphamide and rituximab allowed not only to stop the hemorrhagic syndrome, but also to achieve eradication of the inhibitor.
2026-07-17 | Acquired Hemophilia A Revealing Occult Splenic Marginal Zone Lymphoma.
BACKGROUND Acquired hemophilia A is a rare autoimmune bleeding disorder caused by inhibitory autoantibodies against coagulation factor VIII and is associated with significant morbidity and mortality. Although malignancy-associated acquired hemophilia A is well recognized, its presentation as the initial manifestation of an otherwise clinically subtle indolent B-cell lymphoma, such as splenic marginal zone lymphoma, remains exceedingly uncommon. We report a case highlighting the importance of recognizing acquired factor VIII inhibitors, evaluating for underlying lymphoproliferative disorders, and the potential role of rituximab monotherapy in achieving control of both the inhibitor and the underlying lymphoma. CASE REPORT A 77-year-old man presented with spontaneous bruising and an isolated prolonged activated partial thromboplastin time that failed to correct on mixing studies. Further evaluation demonstrated markedly reduced factor VIII activity, a factor VIII inhibitor, diffuse splenomegaly, and flow cytometry and bone marrow biopsy findings most consistent with splenic marginal zone lymphoma. Treatment with activated prothrombin complex concentrate, corticosteroids, and rituximab resulted in normalization of coagulation parameters, recovery of factor VIII activity, decline in inhibitor titers, resolution of bleeding manifestations, and sustained clinical stability without recurrent bleeding or evidence of lymphoma progression. CONCLUSIONS This case highlights acquired hemophilia A as a rare paraneoplastic manifestation of splenic marginal zone lymphoma and emphasizes the importance of evaluating for an underlying lymphoproliferative disorder in older adults presenting with newly identified factor VIII inhibitors, particularly in the setting of cytopenias or splenomegaly. It also demonstrates that rituximab-based therapy can effectively achieve sustained remission of both the inhibitor and the underlying indolent lymphoma.
2026-07-11 | Prepartum Acquired Hemophilia A: Managing a Double Challenge for Mother and Child.
Acquired haemophilia A (AHA) during pregnancy is exceptionally rare and poses significant risks to both mother and fetus, including maternal hemorrhage and neonatal bleeding due to transplacental transfer of factor VIII (FVIII) inhibitors. We report four cases of antenatally diagnosed AHA to provide insights into management and outcomes. All patients received corticosteroids during pregnancy, with individualized peripartum haemostatic strategies using bypassing agents when indicated. Transplacental FVIII inhibitor transfer occurred in three neonates, leading to transient low FVIII levels; only one mild bleeding event was observed, and all infants achieved spontaneous remission within weeks. Postpartum escalation of immunosuppressive therapy, including rituximab, was required in selected mothers to achieve remission. Our series highlights the critical importance of prepartum diagnosis, allowing optimized maternal haemostatic management, avoidance of traumatic delivery, and structured neonatal surveillance to prevent severe bleeding complications.
2026-08-17 | Acquired haemophilia A associated with prostate cancer managed with recombinant activated factor VII and emicizumab.
Acquired haemophilia A (AHA) is a rare autoimmune bleeding disorder caused by neutralising antibodies against factor VIII. We describe an older man with prostate cancer on active surveillance who presented with spontaneous ecchymoses, progressive anaemia and isolated prolongation of activated partial thromboplastin time. Factor VIII activity was severely reduced, and mixing studies and Bethesda assay confirmed a high-titre factor VIII inhibitor. He achieved initial haemostatic control with recombinant-activated factor VII and was transitioned to emicizumab using an accelerated AHA regimen. No corticosteroids were given inpatient. Emicizumab was used for haemostatic prophylaxis while outpatient once-weekly rituximab was planned for inhibitor eradication. This case highlights early recognition, evaluation for associated malignancy and use of emicizumab as prophylaxis that may allow individualised immunosuppression in selected older patients.
2026-08-12 | Successful management of acquired hemophilia A with life-threatening bleeding and MRSA bacteremia in a hemodialysis patient: importance of a multimodal approach
Abstract Background Acquired hemophilia A (AHA) is a rare and fatal bleeding disorder. AHA in patients undergoing hemodialysis (HD) often leads to impaired hemostasis, necessitating temporary catheters that increase the risk of catheter-related infection. This complication hinders the use of immunosuppressive therapy, often resulting in treatment failure. We herein report the case of AHA in a patient undergoing HD with life-threatening bleeding and MRSA bacteremia, which was successfully managed with a multimodal approach. Case presentation A 64-year-old Japanese man had undergone HD owing to diabetic nephropathy and was admitted to our hospital with a massive hematoma in the left iliopsoas muscle and poor hemostasis at the vascular access site. Hemoglobin (Hb) had dropped to 5.0 g/dL despite daily blood transfusions, and activated partial thromboplastin time was alone prolonged around 60.0 s. Transcatheter arterial embolization (TAE) was performed owing to difficulty in hemostasis. After the diagnosis of AHA was made, 60 mg/day of prednisolone and bypassing agents were introduced. Additional plasma exchange (PE) was performed and rituximab was also administered. Factor VIII (FVIII) inhibitor decreased from 91.0 to 32.0 Bethesda Units (B.U)/mL, and hemostasis was achieved temporarily. Despite a decreasing trend, the FVIII inhibitor titer persisted at a high range. Hb decreased to 5.7 g/dL, and blood transfusions were needed again. Thus, a second TAE and a third PE were performed. After that, FVIII inhibitor improved to 7.0 B.U/mL, and hemostasis was fully achieved. Notably, a temporary dialysis catheter led to methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, necessitating careful PSL tapering. At 6 months after discharge, the patient had not experienced any relapse. Conclusions AHA in patients undergoing HD often leads to difficulty in hemostasis during HD, necessitating temporary catheters that almost induce catheter-related infection. This complication hinders the use of immunosuppressive therapy, sometimes resulting in treatment failure. Given the specific clinical setting of AHA in patients undergoing HD, achieving rapid bleeding control and preparing for impending infections are paramount, which necessitates a well-designed multimodal approach including immunosuppressive therapy and PP (plasmapheresis). This instructive case offers a potential framework for managing similar high-risk patients.
2026-07-17 | Acquired hemophilia a induced by clopidogrel
Introduction . Dual antiplatelet therapy (DATT) with aspirin and a platelet P2Y12 receptor inhibitor is one of the main components of treatment and secondary prevention in patients undergoing percutaneous coronary intervention in acute myocardial infarction. Among the side effects of DATT are hemorrhagic complications caused by the antiplatelet effect of the drugs. Less is known about hemorrhagic complications caused by coagulation disorders when taking clopidogrel. Aim : to present a clinical case of acquired hemophilia A, which occurred in a patient as a result of taking clopidogrel. Main findings . A 68-year-old patient received clopidogrel as part of DATT after percutaneous coronary intervention. One month later, he developed a pronounced hemorrhagic syndrome caused by the appearance of antibodies to coagulation factor VIII (FVIII:C 1.5 %, factor VIII inhibitor 61 BU). The elimination of clopidogrel, hemostatic therapy with eptacog alpha (activated) and immunosuppressive therapy with prednisone, cyclophosphamide and rituximab allowed not only to stop the hemorrhagic syndrome, but also to achieve eradication of the inhibitor.
2026-07-17 | Acquired Hemophilia A Revealing Occult Splenic Marginal Zone Lymphoma.
BACKGROUND Acquired hemophilia A is a rare autoimmune bleeding disorder caused by inhibitory autoantibodies against coagulation factor VIII and is associated with significant morbidity and mortality. Although malignancy-associated acquired hemophilia A is well recognized, its presentation as the initial manifestation of an otherwise clinically subtle indolent B-cell lymphoma, such as splenic marginal zone lymphoma, remains exceedingly uncommon. We report a case highlighting the importance of recognizing acquired factor VIII inhibitors, evaluating for underlying lymphoproliferative disorders, and the potential role of rituximab monotherapy in achieving control of both the inhibitor and the underlying lymphoma. CASE REPORT A 77-year-old man presented with spontaneous bruising and an isolated prolonged activated partial thromboplastin time that failed to correct on mixing studies. Further evaluation demonstrated markedly reduced factor VIII activity, a factor VIII inhibitor, diffuse splenomegaly, and flow cytometry and bone marrow biopsy findings most consistent with splenic marginal zone lymphoma. Treatment with activated prothrombin complex concentrate, corticosteroids, and rituximab resulted in normalization of coagulation parameters, recovery of factor VIII activity, decline in inhibitor titers, resolution of bleeding manifestations, and sustained clinical stability without recurrent bleeding or evidence of lymphoma progression. CONCLUSIONS This case highlights acquired hemophilia A as a rare paraneoplastic manifestation of splenic marginal zone lymphoma and emphasizes the importance of evaluating for an underlying lymphoproliferative disorder in older adults presenting with newly identified factor VIII inhibitors, particularly in the setting of cytopenias or splenomegaly. It also demonstrates that rituximab-based therapy can effectively achieve sustained remission of both the inhibitor and the underlying indolent lymphoma.
2026-07-11 | Prepartum Acquired Hemophilia A: Managing a Double Challenge for Mother and Child.
Acquired haemophilia A (AHA) during pregnancy is exceptionally rare and poses significant risks to both mother and fetus, including maternal hemorrhage and neonatal bleeding due to transplacental transfer of factor VIII (FVIII) inhibitors. We report four cases of antenatally diagnosed AHA to provide insights into management and outcomes. All patients received corticosteroids during pregnancy, with individualized peripartum haemostatic strategies using bypassing agents when indicated. Transplacental FVIII inhibitor transfer occurred in three neonates, leading to transient low FVIII levels; only one mild bleeding event was observed, and all infants achieved spontaneous remission within weeks. Postpartum escalation of immunosuppressive therapy, including rituximab, was required in selected mothers to achieve remission. Our series highlights the critical importance of prepartum diagnosis, allowing optimized maternal haemostatic management, avoidance of traumatic delivery, and structured neonatal surveillance to prevent severe bleeding complications.
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