Lack of factor VIII detection in humans and dogs with an intron 22 inversion challenges hypothesis regarding inhibitor risk.

Background: Almost half of severe hemophilia A (HA) cases are caused by an intron 22 inversion (Int22Inv) mutation, which truncates the 26-exon F8 messenger RNA (mRNA) after exon 22. Another F8 transcript, F8, is initiated from within F8-intron-22. F8 mRNA consists of a short exon spliced to exons 23 to 26 and is expressed in multiple human cell types.

Hemophilia A: Strategies for Improving Long-Term Holistic Management, Adherence, and Quality of Life.

Hemophilia A is a rare inherited bleeding disorder characterized by a deficiency in factor VIII. The evolution of currently approved prophylaxis therapy in hemophilia A will be reviewed, including the clinical value of prophylaxis, real-world experience with prophylaxis, and patient quality-of-life factors that must be considered when choosing treatment options for these patients.

IDELVION: A Comprehensive Review of Clinical Trial and Real-World Data.

Hemophilia B is a bleeding disorder caused by a deficiency of coagulation factor IX (FIX). Treatment with FIX replacement products can increase FIX activity levels to minimize or prevent bleeding events. However, frequent dosing with standard-acting FIX products can create a high treatment burden.

The safety of activated eptacog beta in the management of bleeding episodes and perioperative haemostasis in adult and paediatric haemophilia patients with inhibitors.

Introduction: Haemophilia patients with inhibitors often require a bypassing agent (BPA) for bleeding episode management. Eptacog beta (EB) is a new FDA-approved recombinant activated human factor VII BPA for the treatment and control of bleeding in haemophilia A or B patients with inhibitors (≥12 years of age). We describe here the EB safety profile from the three prospective Phase 3 clinical trials performed to date.

PERSEPT 3: A phase 3 clinical trial to evaluate the haemostatic efficacy of eptacog beta (recombinant human FVIIa) in perioperative care in subjects with haemophilia A or B with inhibitors.

Introduction: Surgical procedures in persons with haemophilia A or B with inhibitors (PwHABI) require the use of bypassing agents (BPA) and carry a high risk of complications. Historically, only two BPAs have been available; these are reported to have variable responses.

Aim: To prospectively evaluate the efficacy and safety of a new bypassing agent, human recombinant factor VIIa (eptacog beta) in elective surgical procedures in PwHABI in a phase 3 clinical trial, PERSEPT 3.

B cell-activating factor modulates the factor VIII immune response in hemophilia A.

Inhibitors of factor VIII (FVIII) remain the most challenging complication of FVIII protein replacement therapy in hemophilia A (HA). Understanding the mechanisms that guide FVIII-specific B cell development could help identify therapeutic targets. The B cell-activating factor (BAFF) cytokine family is a key regulator of B cell differentiation in normal homeostasis and immune disorders.

Hemostatic effect of tranexamic acid combined with factor VIII concentrate in prophylactic setting in severe hemophilia A: A preclinical study.

Background: Hemophilia is characterized by a compromised hemostatic response with delayed development of a clot and the formation of clots that are vulnerable to fibrinolysis. We proposed to study, in vitro and in factor VIII knockout mice (FVIII-KO), whether hemostasis is improved with the addition of tranexamic acid (TXA) to low FVIII plasma concentrations.

Methods: In vitro, blood samples from adults with severe hemophilia-A, spiked to final concentrations of 0-3-10 and 30IU.

The evolution of factor VIIa in the treatment of bleeding in haemophilia with inhibitors.

The use of activated factor VII (FVIIa) for the treatment of bleeding events in haemophilia patients with inhibitors was first reported over 30 years ago. Since then clinical trials, registries, case series, real-world experience and an understanding of its mechanism of action have transformed what was originally a scientific curiosity into one of the major treatments for inhibitor patients, with innovative therapeutic regimens, dose optimization and individualized care now widely practiced. Given current understanding and use, it might be easy to forget the years of clinical research that led up to this point; in this review, we lay out changes based on broad eras of rFVIIa use.

Factor VIII prophylaxis effects outweigh other hemostasis contributors in predicting severe haemophilia A joint outcomes.

Introduction: The Joint Outcome Study (JOS) demonstrated that previously untreated children with severe haemophilia A treated with prophylactic factor VIII (FVIII) concentrate had superior joint outcomes at age 6 years compared to those children treated episodically for bleeding. However, variation in joint outcome within each treatment arm was not well explained.

Aim: In this study, we sought to better understand variation in joint outcomes at age 6 years in participants of the JOS.

A cross-sectional analysis of cardiovascular disease in the hemophilia population.

Men with hemophilia were initially thought to be protected from cardiovascular disease (CVD), but it is now clear that atherothrombotic events occur. The primary objective of the CVD in Hemophilia study was to determine the prevalence of CVD and CVD risk factors in US older men with moderate and severe hemophilia and to compare findings with those reported in age-comparable men in the Atherosclerosis Risk in Communities (ARIC) cohort. We hypothesized if lower factor levels are protective from CVD, we would see a difference in CVD rates between more severely affected and unaffected men.

Factor VIII in Acute Cerebral Ischemia Pilot Study: Biomarker in Patients With Large Vessel Occlusion?

We conducted a prospective serial laboratory cohort study to assess the correlation of factor VIII (FVIII) levels in response to thrombolysis in patients with large vessel occlusion (LVO) and acute ischemic stroke (AIS). Patients with AIS with anterior circulation LVO were eligible for enrollment if treated within 4.5 hours from last seen normal with intravenous tissue plasminogen activator (tPA).

Acquired hemophilia A: Updated review of evidence and treatment guidance.

Acquired hemophilia A (AHA) is a rare disease resulting from autoantibodies (inhibitors) against endogenous factor VIII (FVIII) that leads to bleeding, which is often spontaneous and severe. AHA tends to occur in elderly patients with comorbidities and is associated with high mortality risk from underlying comorbidities, bleeding, or treatment complications. Treatment, which consists of hemostatic management and eradication of the inhibitors, can be challenging to manage.

Clinical outcomes in a cohort of patients with heparin-induced thrombocytopenia.

Background: Heparin-induced thrombocytopenia (HIT) is a thrombotic disorder usually prompting treatment with non-heparin anticoagulants. The benefits and risks of such treatments have not been fully assessed.

Methods: We analyzed data for 442 patients having a positive heparin-platelet factor 4 antibody test and recent heparin exposure.

Prospective, multicenter study of postoperative deep-vein thrombosis in patients with haemophilia undergoing major orthopaedic surgery.

Perioperative clotting factor replacement is administered to reverse the inherent haemostatic defect in persons with haemophilia (PWH), potentially increasing their risk for developing venous thromboembolism (VTE) postoperatively. It was our objective to determine the prevalence of VTE in PWH undergoing total hip or knee arthroplasty (THA, TKA). Patients with haemophilia A or B who underwent THA or TKA were enrolled in this prospective, multicentre observational cohort study.

Clinical and laboratory variability in a cohort of patients diagnosed with type 1 VWD in the United States.

von Willebrand disease (VWD) is the most common inherited bleeding disorder, and type 1 VWD is the most common VWD variant. Despite its frequency, diagnosis of type 1 VWD remains the subject of debate. In order to study the spectrum of type 1 VWD in the United States, the Zimmerman Program enrolled 482 subjects with a previous diagnosis of type 1 VWD without stringent laboratory diagnostic criteria.

Advances in the clinical management of inhibitors in hemophilia A and B.

Inhibitors to factor (F)VIII or FIX are the most serious and challenging complication of hemophilia treatment, increasing morbidity and mortality because bleeds no longer respond to standard clotting factor replacement therapy. For patients with high-titer inhibitors, immune tolerance induction achieved through regular factor exposure is the only proven therapy capable of Inhibitor eradication and is almost always indicated for inhibitors of recent onset. Bypassing therapy is used to treat and prevent bleeding, but neither of the two currently available bypassing agents has the predictable hemostatic efficacy of factor replacement in hemophilia patients without inhibitors.

A Model for Predicting Persistent Elevation of Factor VIII among Patients with Acute Ischemic Stroke.

Background And Purpose: Elevated levels of coagulation factor VIII (FVIII) may persist independent of the acute-phase response; however, this relationship has not been investigated relative to acute ischemic stroke (AIS). We examined the frequency and predictors of persistently elevated FVIII in AIS patients.

Methods: AIS patients admitted between July 2008 and May 2014 with elevated baseline FVIII levels and repeat FVIII levels drawn for more than 7 days postdischarge were included.

Characteristics of hemophilia patients with factor VIII inhibitors detected by prospective screening.

Characteristics of inhibitors identified by prospective screening may differ from those detected clinically. In a prospective study at 17 hemophilia centers with central inhibitor measurement by Nijmegen-Bethesda assay, 23 (2.8%) of 824 hemophilia A patients had new inhibitors detected: nine high-titer inhibitors (HTI: 7 ≥ 5.

Acquired hemophilia A: emerging treatment options.

Acquired hemophilia A is a rare autoimmune disorder caused by an autoantibody (inhibitor) to factor VIII (FVIII) that interferes with its coagulant function and predisposes to severe, potentially life-threatening hemorrhage. Disease management focuses on controlling bleeding, primarily with the use of bypassing therapy and recombinant porcine FVIII, and permanently eradicating the autoantibody using various immunosuppressants. Treatment challenges include delayed diagnosis, difficulty achieving hemostasis and durable remissions, and complications associated with the use of hemostatic and immunosuppressive therapy in a primarily older patient population.

Prevention of bleeding in hemophilia patients with high-titer inhibitors.

Inhibitor development is the most serious adverse event linked to the treatment of hemophilia, as it renders standard hemostatic therapy ineffective. Consequently, inhibitor patients are at increased risk for difficult-to-control bleeding and complications, particularly arthropathy and physical disability. Three randomized clinical trials in patients with inhibitors have demonstrated that compared with on-demand bypassing therapy, prophylaxis with a bypassing agent reduces joint and other types of bleeding and improves health-related quality of life.

How I use bypassing therapy for prophylaxis in patients with hemophilia A and inhibitors.

Inhibitor development poses a significant challenge in the management of hemophilia because once an inhibitor is present, bleeding episodes can no longer be treated with standard clotting factor replacement therapy. Consequently, patients with inhibitors are at increased risk for difficult-to-control bleeding and complications, particularly arthropathy and physical disability. Three clinical trials in patients with inhibitors have demonstrated that prophylaxis with a bypassing agent reduces joint and other types of bleeding and improves health-related quality of life compared with on-demand bypassing therapy.

New Thrombotic Events in Ischemic Stroke Patients with Elevated Factor VIII.

Background. Heightened levels of Factor VIII (FVIII) have been associated with both arterial and venous thrombosis. While elevated FVIII is common during acute ischemic stroke (AIS), whether elevated FVIII confers an increased risk for recurrent thrombotic events (RTEs) following AIS has not been previously explored.

Evaluation of algorithms for the treatment of problem bleeding episodes in patients with hemophilia having inhibitors.

The correlation between real-world clinical decisions and adherence to published treatment algorithms for problem bleeding episodes in patients with severe hemophilia and inhibitors and the resultant impact on clinical outcomes were assessed. Nine cases documenting treatment for problem bleeding episodes in patients with severe hemophilia and inhibitors were retrospectively reviewed. Adherence to treatment algorithms was rated on a scale of 1 to 5, 1 being no adherence and 5 being very high adherence.