Ten‐year experience of recombinant activated factor VII use in surgical patients with congenital haemophilia with inhibitors or acquired haemophilia in Japan

Current status and future prospects of activated recombinant coagulation factor VIIa, NovoSeven®, in the treatment of haemophilia and rare bleeding disorders

rFVIIa, a human recombinant activated coagulation factor VII, has been used worldwide for more than two decades for the treatment of bleeding episodes and prevention of bleeding in patients undergoing surgery/invasive procedures with congenital haemophilia A or B with inhibitors (CHwI A or B), acquired haemophilia (AH), congenital factor VII deficiency and Glanzmann thrombasthenia (GT), refractory to platelet transfusion. The approved dosage, administration and indication of rFVIIa in the US, Europe and Japan differ, depending on the needs of the patient population and regulatory practices. This review presents an overview of the current status and future prospects, including that from a Japanese perspective, of using rFVIIa in the treatment of approved indications. The efficacy and safety of rFVIIa in the approved indications has been demonstrated in several randomised and observational studies and data from registries. The overall incidence of thrombosis across all approved indications in a retrospective safety assessment of clinical trials and registries, prelicensure studies and postmarketing surveillance studies of rFVIIa use was 0.17%. Specifically, the risk of thrombotic events was 0.11% for CHwI, 1.77% for AH, 0.82% for congenital factor VII deficiency and 0.19% for GT. Emerging non-factor therapies such as emicizumab have changed the treatment landscape of haemophilia A, including preventing bleeding in patients with CHwI. However, rFVIIa will continue to play a significant role in the treatment of such patients, particularly during breakthrough bleeding or surgical procedures.

Acquired Haemophilia A: A Review of What We Know

Autoantibodies against plasma coagulation factors could be developed by some individuals inducing severe and sometimes fatal bleedings. This clinical entity is called acquired haemophilia. It should be suspected in subjects with acute abnormal bleedings, without personal or familiar history of congenital bleeding disorders with an unexplained prolonged aPTT. It is rare disease, although its incidence may be underestimated due to the low knowledge about it by many specialists, the frequent use of anticoagulant or antiplatelet therapies in the affected population that can mask the diagnosis and, sometimes, a so withering effect that avoid its confirmation. Mortality ranges between 9% and 33% depending on the series in the first 2 months after diagnosis. This mortality is attributed in up to 40% of the cases to infections in the context of immunosuppressive treatments used to eliminate the inhibitor. Factor VIII levels below 1% and high inhibitor titers are conditions of worse response rates. Advanced age, patient's ECOG, and underlying conditions are key prognostic factors for response to treatment and patient survival. To reduce morbidity and mortality in these patients, it is important to have clinical knowledge and access to guidelines to achieve an early diagnosis and to optimize the haemostatic and immunosuppressive treatment. This review aims to contribute to the dissemination of basic concepts on the epidemiology etiopathogenesis, diagnosis, treatment and management of these patients, as well as risk factors to get remission and the longest overall survival to allow individualized care. Especial awareness will be proposed in patients with some underlying conditions like cancer, autoimmune diseases, children, pregnancy or drugs.

Acquired Hemophilia A: Current Guidance and Experience from Clinical Practice

In acquired hemophilia A (AHA), autoantibodies to coagulation factor VIII (FVIII) neutralize FVIII activity leading to a potentially severe bleeding diathesis that carries a high rate of morbidity and mortality. This disorder is rare and occurs mainly in adults over 60 years of age or in the postpartum period. The diagnosis should be suspected in patients with new-onset bleeding without a personal or family history of bleeding and can be confirmed via specific assays for FVIII inhibitors. Treatment involves both hemostatic therapies to decrease bleeding and immune modulation strategies to re-establish immune tolerance to FVIII. There are limited data on treatment for refractory disease, based mostly on small case series. Registry studies have informed consensus guidelines for optimal hemostatic therapies and initial immunosuppressive therapies. Additional studies are needed to evaluate novel hemostatic agents and develop biomarkers to risk-stratify treatment while limiting adverse events.

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.

Aim

To assess EB safety, immunogenicity and thrombotic potential in children and adults who received EB for treatment of bleeding and perioperative care.

Methods

Using a randomized crossover design, 27 subjects in PERSEPT 1 (12‐54 years) and 25 subjects in PERSEPT 2 (1‐11 years) treated bleeding episodes with 75 or 225 μg/kg EB initially followed by 75 μg/kg dosing at predefined intervals as determined by clinical response. Twelve PERSEPT 3 subjects (2‐56 years) received an initial preoperative infusion of 75 μg/kg (minor procedures) or 200 μg/kg EB (major surgeries) with subsequent 75 μg/kg doses administered intraoperatively and post‐operatively as indicated. Descriptive statistics were used for data analyses.

Results

Sixty subjects who received 3388 EB doses in three trials were evaluated. EB was well tolerated, with no allergic, hypersensitivity, anaphylactic or thrombotic events reported and no neutralizing anti‐EB antibodies detected. A death occurred during PERSEPT 3 and was determined to be unlikely related to EB treatment by the data monitoring committee.

Conclusion

Results from all three Phase 3 trials establish an excellent safety profile of EB in haemophilia A or B patients with inhibitors for treatment of bleeding and perioperative use.

Recombinant FVIIa in elective non-orthopaedic surgery of adults with haemophilia and inhibitors: A systematic literature review

AIM

To assess available evidence on the use of rFVIIa in non-orthopaedic surgery including dental surgery in adult patients with congenital haemophilia with inhibitors (PWHI).

METHODS

A systematic literature search was performed according to a prespecified search string; prespecified criteria were used to select applicable studies including PWHI ≥18 years of age who underwent any non-orthopaedic surgery using rFVIIa.

RESULTS

Thirty-three publications met the eligibility criteria, of which 26 publications - including 46 procedures in 44 patients - were selected for the qualitative analysis. Most publications were case reports or case series (21/26). Primary authors assessed rFVIIa as effective in maintaining haemostasis during and after most major surgeries (22/32). rFVIIa dose was mainly on label, with higher doses used in 4 cases, and a lower dose in 1 case. Duration of treatment was mostly 5-10 days (range: 3 days to 1 month post-operatively). Adverse events related to rFVIIa were rare.

CONCLUSIONS

Assessing non-orthopaedic surgery in this patient population is hampered by a paucity of published data; nevertheless, the current evidence indicates that rFVIIa is effective in achieving haemostasis in haemophilia patients with inhibitors undergoing elective non-orthopaedic or dental surgery. rFVIIa was generally well tolerated in these patients, with thrombotic events occurring rarely. These data, generated to help clinicians manage congenital haemophilia with inhibitors, highlight the need for more systematic reporting of rFVIIa and all other therapeutic agents in non-orthopaedic surgery and dental surgery in patients with congenital haemophilia and inhibitors.

Perioperative Bypassing Agent Therapy for Pulmonary Pleomorphic Carcinoma with Acquired Hemophilia

A 74-year-old man was admitted with lung cancer, and preoperative blood test showed abnormal activated partial thromboplastin time (APTT). Coagulation factor screening and APTT mixing test achieved a diagnosis of acquired hemophilia A (AHA). Bypassing agent therapy was indicated and lobectomy was successfully performed without bleeding complications. APTT returned to normal after the operation without any additional treatment for AHA. The pathogenesis of AHA is still unknown and there is no evidence for hemostatic strategy for AHA patients requiring surgery. This study supports the importance of hemostatic therapy and suggests that malignancy might cause AHA.

Role of orally induced regulatory T cells in immunotherapy and tolerance

Oral antigen administration to induce regulatory T cells (Treg) takes advantage of regulatory mechanisms that the gastrointestinal tract utilizes to promote unresponsiveness against food antigens or commensal microorganisms. Recently, antigen-based oral immunotherapies (OITs) have shown efficacy as treatment for food allergy and autoimmune diseases. Similarly, OITs appear to prevent anti-drug antibody responses in replacement therapy for genetic diseases. Intestinal epithelial cells and microbiota possibly condition dendritic cells (DC) toward a tolerogenic phenotype that induces Treg via expression of several mediators, e.g. IL-10, transforming growth factor-β, retinoic acid. Several factors, such as metabolites derived from microbiota or diet, impact the stability and expansion of these induced Treg, which include, but are not limited to, FoxP3⁺ Treg, LAP⁺ Treg, and/or Tr1 cells. Here, we review various orally induced Treg, their plasticity and cooperation between the Treg subsets, as well as underlying mechanisms controlling their induction and role in oral tolerance.

The role of total ankle replacement in patients with haemophilia and end-stage ankle arthropathy: A review

Haemophilia is the most common X-linked bleeding disorder, affecting over 1 million individuals throughout the world. Patients are subclassified into mild, moderate and severe disease based on per cent factor activity level. Nearly, all patients with haemophilia develop haemophilic arthropathy (HA) by age 30 and HA is known to have a negative impact on physical health subscores in Haem-A-QOL, a validated quality of life scoring system for patients with haemophilia. Unfortunately, many patients progress to end-stage HA of the ankle, which is characterized by pain, contractures, decreased range of motion and muscle atrophy. Ankle arthrodesis (AAD) has been the standard of care in the definitive surgical management of end-stage HA of the ankle. While AAD is a safe surgical procedure known to improve HA-related pain, it decreases functional mobility and has been associated with secondary hindfoot arthritis as well as subtalar degeneration. In recent years, total ankle replacement (TAR) has emerged as an alternative surgical procedure that strives to improve functional mobility, pain and quality of life in end-stage HA of the ankle. However, the safety, durability, and efficacy of this procedure in these patients are unknown. In this review, we analyse the clinical studies investigating TAR in patients with end-stage HA of the ankle. We also discuss important considerations in the perioperative management of patients with haemophilia and compare the risks and benefits of AAD and TAR for patients with end-stage HA of the ankle.

Perioperative laboratory monitoring in congenital haemophilia patients with inhibitors: a systematic literature review

: Although the use of clotting factor concentrates is the mainstay of haemophilia care, the development of inhibitors complicates disease management. Perioperative management of patients with inhibitors is therefore a challenge. A systematic literature review was performed to identify literature reporting on the perioperative monitoring and management of haemophilia. MEDLINE, Embase and Cochrane databases were searched from database inception to 26 March 2018. Recent congress proceedings were also searched. Titles and abstracts, then full texts, were screened for relevance by two reviewers. Quality of included studies was assessed using the Critical Appraisal Skills Programme checklist. Of the 2033 individual entries identified, 86 articles met the inclusion criteria. The identified studies were screened again to find articles reporting perioperative laboratory monitoring in patients with congenital haemophilia A or B, resulting in 24 articles undergoing data extraction. Routine perioperative assay monitoring practices were the most commonly reported (n = 20/24); thrombin generation assay was the least commonly reported (n = 2/24). Other monitoring practices described were factor VII and factor VIII coagulation activity (n = 8/24, n = 5/24, respectively), and thromboelastography or rotational thromboelastometry assessments (n = 3/24). The impact of monitoring on treatment decisions was, however, rarely reported. In conclusion, many methods of perioperative monitoring of haemophilia patients with inhibitors have been identified in this review, yet there is a lack of reporting in larger scale cohort studies. More detailed reporting on the impact of monitoring outcomes on treatment decisions is also needed to share best practice, particularly as new therapeutic agents emerge.

Over two decades of orthopaedic surgery in patients with inhibitors-Quantifying the complication of bleeding

Patients with haemophilia who have developed inhibitors against factor VIII (FVIII) or factor IX present a significant concern to those surgeons who operate on them. The evidence base for bypassing agents such as recombinant factor VIIa and activated prothrombin complex concentrate has amassed over several decades. The literature is open to positive interpretation on the successful use of these agents in the treatment of inhibitor-positive patients. However, there are equally persistent concerns amongst surgeons, in particular orthopaedic surgeons, regarding the high complication rate of bleeding. To explore and quantify this concern, we present a literature review spanning two decades of publications on haemophilia patients with inhibitors undergoing orthopaedic surgery. Irrespective of the progress made with haemostatic protocols, trepidation on embarking on surgery is valid. The high risk of bleeding is a function of the inherent complexity of the disease and rightfully translates into difficulties in its management. Combined with the prospect of orthopaedic surgery, those involved in the care of such patients are justified in their continued anxiety and diligence when considering the benefits in quality of life against the prevalent complications.

Continuous infusion of recombinant activated factor VII: a review of data in congenital hemophilia with inhibitors and congenital factor VII deficiency

Introduction

Continuous infusion (CI) of clotting factors as a replacement therapy for perioperative hemostatic protection has been performed for many years, including with factors VIII and IX and recombinant activated factor VII (rFVIIa). This approach provides steady factor levels without requiring frequent administration of bolus doses.

Aim

To review safety, efficacy, and dosing data regarding CI of rFVIIa for hemostatic management of patients with congenital hemophilia with inhibitors (CHwI) or congenital factor VII deficiency (C7D).

Materials and methods

A literature review identified instances of CI of rFVIIa in patients with CHwI or C7D undergoing surgery or experiencing bleeding episodes. Data regarding safety, efficacy, and dosing were extracted.

Results

The safety and efficacy of 50 mcg/kg/h CI of rFVIIa following a 90 mcg/kg bolus injection, vs a standard bolus injection regimen, was reported for 24 patients with CHwI undergoing elective surgery in an open-label, randomized, Phase III trial. Efficacy was similar between CI and bolus injection groups at all postoperative time points assessed. Additionally, a postmarketing surveillance study reported effective (80%) and partially effective (20%) CI of rFVIIa in a Japanese cohort of ten patients with CHwI who underwent 15 surgical procedures. Finally, the safety and dosing of rFVIIa CI in 193 and 26 patients with CHwI and C7D, respectively, were reported in 11 prospective studies, 10 retrospective studies, and 30 case reports. No unexpected safety findings were reported.

Conclusion

rFVIIa CI has been performed safely and effectively in patients with CHwI and C7D undergoing surgery and during bleeding episodes in patients with CHwI.

The role of recombinant activated factor VII in the haematological management of elective orthopaedic surgery in haemophilia A patients with inhibitors

The clinical profile and expectations of haemophilic patients with inhibitors have changed over the last three decades, mainly because of the prolongation of life-expectancy, often resulting in an increase of the orthopaedic burden. Recombinant activated factor VII (rFVIIa) is the most frequently used bypassing agent in haemophilia patients with inhibitors during elective orthopaedic surgery. For nearly 30 years, rFVIIa has been successfully used to control haemostasis in several major and minor surgical procedures. Clinical trials, case series, reports and surveys were progressively aimed at optimising rFVIIa usage in very demanding conditions managed in highly specialised centres. Recommendations from consensus opinions and guidelines have been provided on the basis of this clinical experience.

Clinical characteristics and outcomes of acquired hemophilia A: experience at a single center in Japan

Acquired hemophilia A (AHA), which is caused by autoantibodies against coagulation factor VIII (FVIII) is a rare, life-threatening bleeding disorder, the incidence of which appears to be increasing in Japan as the population ages. However, the clinical characteristics, treatment, and outcomes of AHA remain difficult to establish due to the rarity of this disease. We retrospectively analyzed data from 25 patients (median age 73 years; range 24-92 years; male n = 15) diagnosed with AHA between 1999 and 2015 at Gunma University Hospital. We identified autoimmune diseases and malignancy as underlying conditions in four and three patients, respectively. Factor VIII activity was significantly decreased in all patients (median 2.0%; range <1.0-8.0) by FVIII inhibitor (median 47.0 BU/mL; range 2.0-1010). Among 71 bleeding events, subcutaneous or intramuscular hemorrhage was the most prevalent. Seventeen patients required bypassing agents. Twenty-two (91.7%) of 24 patients treated with immunosuppressive agents achieved complete response (CR) during a median of 57.5 days (range 19-714 days). Although three patients (12%) relapsed and seven (28%) died of infection, none of the deaths were related to bleeding. Although most of our patients achieved CR after immunosuppressive therapy, the rate of infection-related mortality was unsatisfactorily high.