Prophylactic recombinant factor VIIa in haemophilia patients with inhibitors

Prevention of bleeding, especially into joints, with prophylactic factor infusions is the most effective treatment for severe haemophilia patients. Approximately 15-30% of patients with factor VIII deficiency and 3-5% of patients with factor IX deficiency develop neutralizing antibodies (inhibitors) to factor precluding their use. Such patients often have significant bleeding complications including life- and limb-threatening bleeds and severe joint disease. Prophylaxis for such patients is not generally considered because of the fact that the standard (bypassing) agents for such patients are not as effective as natural factor replacement, because of concerns for thrombotic complications and also because of the very high cost of bypassing agents. We treated two patients with high titre inhibitors with prophylactic recombinant factor VIIa (rFVIIa). The first patient was treated as a result of development of a target joint and to reduce the use of agents that can lead to anamnesis of his inhibitor. The second patient had multiple severe bleeds and was hospitalized 20% of the time over a 2-year period. He had a very poor quality of life. Both patients had shown good responses previously to rFVIIa for treatment of bleeds. Both patients had an outstanding response to prophylaxis albeit at a very high cost. Prophylaxis with rFVIIa can be an effective approach in select inhibitor patients with severe complications related to bleeding.     

Case studies: orthopaedic surgery in adult patients with haemophilia A with inhibitors

Summary.  Whilst orthopaedic surgery in haemophilia patients without inhibitors is now relatively common in specialized centres, until recently there have been only a few sporadic instances of surgery having been undertaken on patients with inhibitors. The availability of recombinant activated factor VII (rFVIIa) for haemostatic cover during surgery allows procedures to be performed that previously may not have been considered possible. Complications associated with thrombosis are rare in haemophilia patients with inhibitors, but bleeding complications remain a concern. Globally, experience of performing orthopaedic surgery in these patients is increasing and many successful outcomes have been reported. However, more knowledge relating to the incidence and type of bleeding complications liable to be encountered, together with further information about appropriate rescue treatment, would be valuable. Data relating to long-term follow-up after surgery would be useful, as would a comparison of outcomes between haemophilia patients with and without inhibitors. Optimal dosing regimens for rFVIIa as surgical cover are still to be determined and further information is required relating to the cost effectiveness of rFVIIa in surgery. Further study should address these issues.     

Management of haemophilic patients with inhibitors in major orthopaedic surgery by immunadsorption, substitution of factor VIII and recombinant factor VIIa (NovoSeven®): a single centre experience

Inhibitors of factor VIII or FIX in haemophilic patients are a common and serious complication associated with an increased risk of life-threatening bleeding during elective surgery. Substitution therapy fails to be effective, therefore an alternative treatment is needed. We have performed six major elective orthopaedic interventions in four patients with haemophilia A and inhibitors. A preoperative immunadsorbant therapy with Therasorb to eliminate inhibitors was successful in four cases, but during FVIII substitution inhibitors increased on day 4 to day 6 after surgery, leading to decreasing FVIII levels. Therefore, therapy was changed to recombinant FVIIa (rFVIIa; NovoSeven). Two interventions had to be covered with sole rFVIIa therapy as immunadsorbant therapy failed to be effective in one case and the need for acute intervention did not allow pretreatment in the other. We did not see increased bleeding during or after surgery when compared to our experience with non-inhibitor haemophilic patients. In conclusion, a preoperative decrease of inhibitors from immunadsorbant therapy, perioperative substitution of FVIII and changing treatment to rFVIIa when inhibitors are increased, is a safe and economic therapy for guaranteeing haemostasis in major elective orthopaedic surgery. On the contrary, sole therapy with rFVIIa allows immediate surgical intervention without a long hospital stay prior to surgery and a need for laboratory monitoring of inhibitor titres and FVIII levels. Our findings support data previously published.     

Recombinant factor VIIa in the management of surgery and acute bleeding episodes in children with haemophilia and high responding inhibitors

The management of acute and surgical bleeding episodes in children with severe factor VIII or IX deficiency who develop high responding inhibitors presents a major therapeutic challenge to clinicians. Recombinant factor VIIa (rVIIa) is an effective, reliable and safe treatment that can be used to treat acute bleeding episodes prior to commencing an immune tolerance programme and to cover surgical procedures until the immune tolerance programme is successful. In a significant minority of patients, immune tolerance therapy is ineffective and an alternative haemostatic agent such as rVIIa is required for life-long treatment. The present study evaluated the use of rVIIa in a paediatric setting. Twelve children, aged 1-16 years, were treated successfully with rVIIa to prevent surgical bleeding in 20 surgical procedures (19 central venous access device insertion or removal, 1 dental extraction). Minor postoperative haematomata developed in 2 out of 20 cases after regular rVIIa therapy had been discontinued and resolved with a short course of rVIIa in both cases. Three children had six life- or limb-threatening bleeding episodes. All bleeding episodes resolved with regular rVIIa treatment although topical fibrin glue was needed in one child with a frenulum tear. One patient required two red cell transfusions for symptomatic anaemia resulting from two separate bleeding episodes. The rVIIa therapy was well tolerated and there was no evidence of treatment-related complications. We conclude that rVIIa is the treatment of choice for the management of surgery and acute life- or limb-threatening bleeding in children with haemophilia and high responding inhibitors.     

Prophylaxis in haemophilia patients with inhibitors

Summary.   The presence of high titre inhibitors makes the treatment of bleeding episodes in haemophilia patients difficult and increases the risk of uncontrollable bleeding and disability, despite optimum on-demand treatment with bypassing agents. The inability to effectively control joint bleeding leads to progressive joint disease in many patients with inhibitors. Significant mobility impairments are far more prevalent in patients with inhibitors than in those without inhibitors. Emerging data suggest that prophylaxis using bypassing agents may be effective and safe in reducing the incidence of joint bleeding during immune tolerance induction (ITI), and for patients who failed ITI or who were never candidates for ITI. Only controlled clinical trials will ultimately demonstrate whether prophylaxis can prevent joint bleeding and damage, and improve quality of life in patients with inhibitors. This article will review the published data on the use of bypassing agents in the prevention of bleeding, and will discuss ongoing clinical prophylaxis trials in inhibitor patients.     

Cost minimization analysis to compare activated prothrombin complex concentrate (APCC) and recombinant factor VIIa for haemophilia patients with inhibitors undergoing major orthopaedic surgeries

Summary. Benefits of bypassing agents for maintaining haemostasis in major surgeries have been described in the literature; however, their use has a substantial economic impact. This study assessed the cost of FEIBA, an activated prothrombin complex concentrate and recombinant factor VIIa (rFVIIa) when used in inhibitor patients undergoing major surgeries. After reviewing published literature, a cost minimization model was developed describing dosing regimens recommended and used during major surgeries for FEIBA (pre‐operative: 75–100 U kg⁻¹; postoperative: 75–100 U kg⁻¹ q 8–12 h days 1–5 and 75–100 U kg⁻¹ q 12 h days 6–14) and rFVIIa (pre‐operative: 90 μg kg⁻¹; intra‐operative: 90 μg kg⁻¹ q 2 h; postoperative: 90 μg kg⁻¹ q 2–4 h days 1–5 and 90 μg kg⁻¹ q 6 h days 6–14). Using a 75 kg patient and US prices, total drug cost was calculated for three scenarios: use of FEIBA or rFVIIa alone and a third case combining rFVIIa pre‐ and intra‐operative and FEIBA throughout a 14‐day postoperative period. Dosage amounts of modelled bypassing agents were similar to cases in the literature. Using FEIBA instead of rFVIIa would decrease total drug cost by >50% and save over $400 000 per surgery. Sequential use of both bypassing agents would increase total drug cost by 9% when compared with FEIBA alone, but would remain >40% lower than rFVIIa alone. Univariate sensitivity analyses confirmed robustness of results. As large amounts of bypassing agents are necessary for patients with inhibitors to undergo major surgeries, cost is a major consideration. Use of FEIBA alone or in combination with rFVIIa has emerged as a cost‐saving approach.     

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

Patients with congenital haemophilia with inhibitors or acquired haemophilia are at risk of bleeding complications during surgery. In these patients, replacement therapy for the missing coagulation factor is ineffective, and a bypassing agent such as recombinant activated factor VII (rFVIIa) is required to manage bleeding. To evaluate the safety and haemostatic efficacy of rFVIIa treatment in Japanese patients with congenital haemophilia with inhibitors to FVIII/FIX or acquired haemophilia undergoing surgery. Postmarketing surveillance data from May 2000 to March 2010 were analysed to assess the haemostatic efficacy of 38 procedures in 22 patients with congenital haemophilia A, 13 procedures in seven patients with congenital haemophilia B, and five procedures in five patients with acquired haemophilia. Postoperative bleeding control was judged to be effective (bleeding was stopped completely or reduced considerably) for 34/38 procedures (89%) in patients with congenital haemophilia A, 10/13 procedures (77%) in patients with congenital haemophilia B, and 4/5 procedures (80%) in patients with acquired haemophilia. Tranexamic acid was used concomitantly for 36/56 procedures (64%). Safety was analysed for 66 procedures in 37 patients. Adverse effects potentially related to rFVIIa treatment included mild superficial thrombophlebitis, mild decrease in platelet count, and mild elevation of the serum alanine transaminase level in one patient each. All adverse effects resolved without treatment. Administration of rFVIIa provided adequate haemostasis without serious adverse effects in the majority of cases. The efficacy and safety data in Japanese patients were similar to previously published data from other countries.     

Efficacy of recombinant factor VIIa administered by continuous infusion to haemophilia patients with inhibitors

We have prospectively monitored treatment of haemophilia patients with inhibitors by recombinant factor VIIa (rFVIIa) administered by continuous infusion to obtain more insight in the underlying factors of the clinical efficacy of this administration method. At present, 43 treatment episodes of 14 different Dutch haemophilia inhibitor patients are included in the database. Analysis of the data showed a discrepancy between the efficacy of rFVIIa continuous infusion treatment of acute and surgical bleeds in the oral cavity [one (14%) effective, two (29%) partially effective, four (57%) not effective] and other parts of the body [29 (80%) effective, four (11%) partially effective, two (6%) not effective, one (3%) impossible to classify]. Patients who had acute or surgical oral cavity bleeds, uncontrolled by rFVIIa continuous infusion, reacted favourably to rFVIIa continuous infusion in other locations of the body. Acute bleeding episodes in the oral cavity, which could not be controlled by rFVIIa continuous infusion, stopped when the treatment regimen was switched to rFVIIa bolus injections. Finally, haemostatic control during dental extractions was excellent after the initial rFVIIa bolus injection preceding the continuous infusion, but rebleeds occurred in all patients within 48 h under rFVIIa continuous infusion coverage. These observations suggest that the efficacy of rFVIIa continuous infusion depends, at least in part, on the location of the body in which the bleeding occurs and that rFVIIa bolus injections are more effective than rFVIIa continuous infusion in the oral cavity. We hypothesize that the inability of rFVIIa continuous infusion treatment to sufficiently inhibit fibrinolysis is the underlying cause of the decreased efficacy of rFVIIa continuous infusion treatment in the oral cavity.     

Severe acquired haemophilia A treated with recombinant factor VIIa

Acquired haemophilia can be associated with various conditions including pregnancy, autoimmune diseases and lymphoproliferative disorders, though often no underlying cause is found. It often presents with a rapid onset of muscle bleeding and involves the IgG antibody. It may be treated with human or porcine factor VIII (FVIII), prothrombin complex concentrates, factor IX (FIX) complex concentrates, factor VIIa (FVIIa) or by immunosuppression. We report a case of acquired haemophilia in a 40-year-old woman diagnosed following laparotomy. She was treated unsuccessfully using human FVIII and cryoprecipitate, porcine FVIII and FIX complex concentrate, before being treated with recombinant FVIIa (NovoSeven, Novo Nordisk). On treatment with recombinant FVIIa, bleeding stopped rapidly with no side-effects and the abdominal haematoma was evacuated with minimal post-operative bleeding.     

Comparison of kaolin and tissue factor activated thromboelastography in haemophilia

Summary. A limitation of bypassing agent therapy for haemophilia patients with inhibitors is the absence of a laboratory assay, which predicts the clinical response to treatment. Recent investigations have demonstrated the potential for thromboelastography to assess the effects of bypassing agent therapy in this patient population. While tissue factor activation has been used in several prior studies, a recent multicentre study failed to demonstrate an expected concentration–response effect of rFVIIa and called into question the tissue factor activation methods that have been employed. A comparison of kaolin to two concentrations of tissue factor as the activation method for thromboelastography was investigated in patients with haemophilia. We performed kaolin and tissue factor activated thromboelastography on blood from inhibitor and non‐inhibitor patients with and without addition of rFVIIa and rFVIII. The results demonstrate that kaolin leads to a longer R, K and angle than the higher dilution of tissue factor (1:17 000) at baseline (no factor) and after addition of rFVIIa for both the inhibitor and non‐inhibitor patients. Kaolin led to a longer R and K in comparison to a low dilution of tissue factor (1:42 000) following the addition of rFVIIa in the inhibitor patients. The longer R and K allows for better discrimination of the effects of rFVIIa thus making kaolin the most sensitive activation method in this setting. Thus kaolin activated thormboelastography should be considered an effective, perhaps the most effective, activator when utilizing thromboelastography to assess the effects of rFVIIa in haemophilia patients with inhibitors.     

U.S. survey of surgical capabilities and experience with surgical procedures in patients with congenital haemophilia with inhibitors

General guidelines exist for the use of recombinant activated factor VII (rFVIIa) to maintain haemostasis during surgery in congenital haemophilia A and B patients with high responding inhibitors (CHwI). Individual surgical plans are required and based upon historical therapy response, adverse events and anticipated procedure. Surgical interventions are feasible, yet it remains unclear how many US hemophilia treatment centres (HTCs) perform procedures in this fragile population. To better understand the US HTC surgical experience in CHwI patients and the number/types of procedures performed, a 21-question survey was sent to 133 US HTCs, with follow-up for response clarification and to non-responders. 98/133 HTCs (74%) responded, with 87 currently treating CHwI patients. In the last decade, 76/85 HTCs performed 994 surgeries on CHwI patients. Sites were experienced in the following procedures: central line insertion/removal (73 HTCs), dental (58), orthopaedic (52), abdominal (23), cardiovascular (14) and otolaryngologic (11). Experience with orthopaedic surgeries included synovectomies - arthroscopic (23 HTCs), radioisotopic (22), and open (7); joint replacement (18); fracture repair (14); and arthrodesis (8). Treatment modalities included rFVIIa bolus (83 HTCs) or continuous infusions (9), plasma-derived activated prothrombin complex concentrate (pd-aPCC) (55), antifibrinolytics (51), topical haemostatic agents (29), factor VIII (16) and fibrin sealants (14). Protocols for bypassing agents were used by 31/92 (33%) HTCs. Most US HTCs surveyed care for CHwI patients (74%) and have experience in minor surgery; fewer HTCs reported complex orthopaedic surgical experience. Identification of best practices and surgical barriers is required to guide future initiatives to support these patients.     

Excision of pseudotumour in a patient with haemophilia A and inhibitor managed with recombinant factor VIIa

We describe a patient with haemophilia A and factor VIII inhibitor who underwent surgical excision of a large pseudotumour in the left femoral region. Haemostasis was successfully maintained with bolus doses of recombinant factor VIIa at 2-h intervals and anti-fibrinolytic therapy, and the pseudotumour was removed. Subsequently, the dose interval was gradually prolonged to 8 h for a total of 18 days. Although a spontaneous haemorrhage was observed on postoperative day 8, haemostasis was achieved by reducing the dosage interval. No adverse event occurred during the course of treatment.     

Real‐world outcomes with recombinant factor VIIa treatment of acute bleeds in haemophilia patients with inhibitors: results from the international ONE registry

The ONE Registry (OR) was an international prospective observational study of on‐demand recombinant factor VIIa (rFVIIa) treatment for mild to moderate bleeds in haemophilia A/B patients with inhibitors. To describe real‐world use of single and multi dose rFVIIa and to compare outcomes, including effectiveness, safety, quality of life and treatment satisfaction associated with treatment. Baseline data included demographics, treatment, medical and bleed history and patient/caregiver‐reported outcomes regarding bleeds. rFVIIa was prescribed according to routine practice; regimens varied and initial dose was categorized as low (LD, ≤120 μg kg^?1), intermediate (ID, >120 and <250 μg kg^?1) or high (HD, ≥250 μg kg^?1). OR included 102 patients and 85 (83%) reported 494 bleeds overall. Mean age was 23 years (SD 16.4), with 52% ≥18 years. Majority of bleeds (n = 350, 71%) involved ≥1 joints; 46% involved a target joint. Median initial dose was 90 μg kg^?1 in LD (range 87–120, n = 156), 174 μg kg^?1 in ID, (range 121–249, n = 127) and 270 μg kg^?1 in HD, (range 250–375, n = 211). For spontaneous bleeds, effective haemostasis rate at 9 h was 63% LD, 60% ID and 56% HD. Rates of combined partially effective/effective haemostasis was 85% LD, 96% ID and 86% HD. Median number of doses in HD was one (range 1–7), compared with two in LD (range 1–17) and ID (range 1–23). No thromboembolic events were reported in 1145 doses given. These observational data in real life are consistent with previous studies which have shown similar overall effectiveness of rFVIIa and similar effectiveness and safety across different patterns of standard initial dosing.     

Surgical interventions in a cohort of patients with haemophilia A and inhibitors: an experiential retrospective chart review

Strategies for the management of perioperative bleeding in patients with haemophilia and inhibitors have evolved rapidly as a result of the development of the bypassing agents Factor Eight Inhibitor Bypassing Activity, Anti-inhibitor Coagulant Complex (FEIBA) and activated recombinant factor VII (rFVIIa). However, there are currently no established guidelines for perioperative use of bypassing agents, and few controlled clinical studies have been carried out. Thus, case reports, such as those presented here, provide useful anecdotal evidence to guide the treatment of inhibitor patients. The purpose of this report was to describe experiences in the use of bypassing agents in a small cohort of patients with haemophilia A and inhibitors undergoing surgical procedures. Cases from five treatment centres were reviewed. Twenty-two procedures using FEIBA, rFVIIa or a combination of both agents were compiled from seven inhibitor patients (six with an alloantibody inhibitor and one with an acquired autoantibody inhibitor). Eleven procedures used FEIBA monotherapy, two employed rFVIIa monotherapy and nine were performed using combination therapy. Supplemental therapies were required to manage bleeding in some cases. Haemostatic control was achieved in all cases, and treatment regimens were generally well tolerated. One thrombotic adverse event was reported: evidence of disseminated intravascular coagulation (DIC) was found after rFVIIa use in one case, although the direct cause of DIC was unknown. The experiences in this case review demonstrate that both major and minor surgical procedures can be safely performed in patients with haemophilia and high-titre inhibitors under the cover of bypassing agents, with a high expectation of success.     

Spinal epidural haematoma in haemophilia A with inhibitors – efficacy of recombinant factor VIIa concentrate

We report the case of a 21-year-old man with severe haemophilia A and factor VIII inhibitors who presented with an extensive spinal epidural haematoma (C2-T12), probably induced by sit-up exercises. The bleed was defined by magnetic resonance imaging of the cervical and thoracic spine and prompt treatment with recombinant factor VIIa concentrate led to complete resolution at 4 weeks. Neurological sequelae were averted and surgical decompression was not necessary. We discuss the difficulties in diagnosis and management of such a case.     

Antibodies to factor VIIa in patients with haemophilia and high-responding inhibitors

The haemostatic effect of by-passing agents such as activated prothrombin complex concentrates (aPCC) and recombinant factor VIIa is inadequate in some patients with severe haemophilia and high-responding inhibitors. Theoretically, this could be due to antibody reactivity to procoagulant proteins other than the deficient factor. To evaluate this hypothesis, immunoglobulin (Ig) fractions from six multi-transfused patients (three haemophilia A and three haemophilia B) were purified on protein A sepharose and then subjected to immunoaffinity chromatography on factor IX sepharose and factor VIIa sepharose. All three Ig fractions from the haemophilia B patients, but not commercially available Ig, contained antibodies that bound to both gels. None of the haemophilia A patients had antibodies to factor IX but all three had antibodies towards factor VIIa. The immunoaffinity purified antifactor IX and VIIa antibodies from the haemophilia B patients inhibited thrombin formation in vitro using Feiba as active enzyme, but had no significant effect in the presence of NovoSeven. In contrast, no inhibitory effect was observed with the antifactor VIIa antibodies from the haemophilia A patients. Cross-reactivity to factor IX was seen for the antifactor VIIa antibodies from the patients with haemophilia B. Our findings show that antibody reactivity to other procoagulant factors such as factor VIIa exists in patients with high-responding inhibitors and that these antibodies may have an inhibitory potential that correlates to the amount of active enzyme present. The characterization of the antibody profile may facilitate an optimal treatment with by-passing agents in severe bleeding events.     

Home treatment of haemophilia patients with inhibitors

Summary. Bleeding episodes in patients with inhibitors can be challenging to treat. Clinical guidelines recognize the importance of early treatment, ideally within 2 h of the onset of bleeding. On‐demand haemophilia care at home has been shown to reduce the time between recognition of the symptoms of bleeding and initiation of treatment. Rapid resolution of bleeding is associated with longer‐term benefits for the patient. Effective haemophilia care at home depends on patients and carers taking greater responsibility for treatment; however, many find this difficult. Education can help raise awareness of haemophilia treatment at home and provide helpful information for patients/carers. The haemophilia nurse has a key role in providing this support and education. This review discusses a number of recent guidelines and educational materials for haemophilia home care identified during a literature survey. The survey shows that most materials were not validated. In addition, the survey shows limited effectiveness data on techniques for training haemophilia patients about home care. Further education resources and research in the treatment of haemophilia at home are required.     

Use of recombinant factor VIIa (NovoSeven) in a haemophilia A patient with inhibitor in Kuwait

Development of inhibitors is a known complication in some haemophiliacs receiving coagulation factor replacement therapy. We report on the successful management of a young boy with haemophilia A with inhibitor using recombinant factor VIIa. We had failed to control bleeding in this patient following his circumcision, despite infusion with high doses of factor VIII concentrate for 2 weeks. Recombinant factor VIIa is a useful 'factor VIII bypassing agent' for the control of bleeding in patients with haemophilia A and B who develop inhibitors. We suggest that severely affected haemophiliacs should be absolved of ritual circumcision as a protective measure against what might become a life-threatening haemorrhage - especially in those with inhibitors.     

Healthcare resource utilization among haemophilia A patients in the United States

Summary. Advances in therapy have improved life expectancy and quality of life of patients with haemophilia A. Due to the chronic and complex management of this disease, particularly, the development of inhibitors, little is known about their health resource utilization in the real‐life setting over time. The aim was to assess the distribution and trend of healthcare resource utilization among US haemophilia A patients with and without inhibitors. The MarketScan® Database, was queried to identify individuals with ≥1 year continuous enrolment, two medical diagnoses of haemophilia A and claims for factor VIII or bypassing agent (to infer inhibitor status) during 2001–2007. Haemophilia‐related cost was estimated from inpatient, outpatient and pharmacy claims. Annual cost differences were assessed by age and over a 4‐year period for those with continuous enrolment. Among 51 million covered lives, 1044 haemophilia patients were identified, of whom 981 (94%; mean age = 21.2 years) did not have an inhibitor. The median haemophilia‐related cost for these patients was $63,935 per patient per year. When normalized by weight, annual cost was stable (no statistically significant differences) among 312 non‐inhibitor patients (mean age = 21.8 years) with 4‐year continuous data. While there was a wide distribution of haemophilia‐related cost among the 63 individuals with an inhibitor (mean age = 15.4 years), only 0.6% of the total haemophilia patients had costs exceeding $1 million per patient per year. This study indicated that most haemophilia A patients were inhibitor‐free with relatively stable annual costs over time. There was a wide distribution of haemophilia‐related cost for inhibitor patients, while the proportion of patients who incurred extreme high cost was low.