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About 5000 people in Italy suffer from hemophilia, the most common coagulation disorder. As for other chronic diseases, even in the case of hemophilia, the engagement of the patient is essential: the patients, in fact, must be empowered and helped to become strong partners of the care team and sensitized with respect to their rights and duties for the successful achievement of the goals set by their healthcare path. Hence the initiative to start a new research-intervention project in the field of hemophilia. The study had different phases of research: a first moment inspired by the principles of narrative medicine, aimed at collecting stories and narratives of patients with hemophilia related to the experience of the disease and therapy and expectations of active involvement in the relationship with the clinician. At the same time, among hematologists and patients has been surveyed the experience of therapeutical relationship and communication, to capture the aspects in which they feel effective and the areas of improvement and unmet needs. Subsequently, a workshop dedicated to patients and hematologists was organized to foster mutual awareness between these two targets and the formation of a better communication and relational skills of clinicians. The results of the project formed the basis for a policy brief document, aimed at disseminating recommendations to support better relationship and empathic communication between clinicians and patients.

Introduction: Haemophilia management and patients’ quality of life significantly improved. However, data on current patients’, caregivers’ and clinicians’ satisfaction and limitations of treatments and haemophilia management are limited. Aim: Assessing the management satisfaction and unmet needs from the perspective of Italian patients with haemophilia (PWH) without inhibitors (or caregivers if children) and of specialist physicians. Methods: Surveys (for patients≥18 years, caregivers of children and haemophilia specialists) were developed by a multidisciplinary working group and conducted from November 2019 to June 2020. Results: Among 275 participants, 120 (43.6%) were PWH without inhibitors, 79 (28.7%) caregivers and 37 (13.4%) clinicians. Patients and caregivers perceived a higher control of the disease compared to clinicians. However, more than 40% of patients and caregivers reported to feel significantly conditioned by the risk of bleeding during their daily life. PWH reported a 6-month mean/median (range) of bleeds 2.3/.0 (0-24) and caregivers 1.3/.0 (0-16) in children. The treatment burden (frequency of administration) was not satisfactory for more than half adults and caregivers of children treated with prophylaxis. A good access to treatment, haemophilia centres and medical service was reported, with issues associated to the multidisciplinary approach and treatment at emergency department. Conclusions: This large national study provides an updated overview of haemophilia care in Italy from different points of views, highlighting positive aspects and unmet needs. This information can guide future interventions to improve haemophilia management and the assessment of impact of new treatment options.

rVIII-SingleChain is indicated for treatment and prophylaxis of bleeding in patients with haemophilia A (HA). The safety and efficacy of rVIII-SingleChain have previously been shown in the AFFINITY clinical trial programme. This survey evaluated clinical experience following a switch to rVIII-SingleChain from the perspective of both physicians and patients. A web-based survey (July–September 2019) involving 14 Haemophilia Treatment Centres (HTCs) collected data about HA patients who were under treatment with rVIII-SingleChain for ≥ 12 months, as reported by their physicians. In addition, about half of these patients were separately interviewed. Out of 91 patients receiving rVIII-SingleChain in the 14 participating HTCs, 48 had been treated for ≥ 12 months; among those 48, 38% were ≤ 18 years, 37% 19–40 years and 25 % ≥ 41 years; 73% of them had severe HA and 85% were being treated with prophylactic therapy. Twenty-six patients accepted to be separately interviewed: mean age was 30 years; 62% had severe HA and 85% were receiving prophylaxis. Focusing on those patients who were already in prophylaxis with prior FVIII (all but one with recombinant factors), infusion frequency was significantly reduced from 3–2 per week following the switch to rVIII-SingleChain (mean, 2.74 vs. 2.44, respectively; p=0.013), as reported by physicians; the rate of patients needing 3 infusions per week dropped from 74% with previous products to 44% with rFVIII-SingleChain. The annual mean factor consumption was 4740 IU/Kg (median, 4500 IU/Kg; min, 2.215 IU/Kg; max, 7.200 IU/Kg) with prior product and 4320 IU/Kg (median, 4320 IU/Kg; min, 2.215 IU/Kg; max, 6.646 IU/Kg) with rVIII-SingleChain. Both physicians and patients reported a significant reduction in annual total bleeding rates with rVIII-SingleChain compared with prior product (mean 2.15–0.96 and 2.46–0.71 events/year, p = 0.031 and p = 0.018, respectively). Mean satisfaction ratings (from 1; dissatisfied, to 5; very satisfied) for rVIII-SingleChain were quite high for both physicians (4.14, 86% satisfied/very satisfied) and patients (4.18, 86% satisfied/very satisfied). This survey suggested that switching to rVIII-SingleChain allowed patients to reduce their injection frequency without increasing factor consumption or compromising clinical results. Both physicians and patients reported a positive experience with rVIII-SingleChain after 1 year of treatment.

BACKGROUND Immune tolerance induction (ITI) is the only proven strategy to eradicate factor VIII inhibitors in patients with haemophilia A (HA). AIM To identify patients and treatment options with the highest chance of inhibitor eradication by primary ITI. PATIENTS AND METHODS In the frame of the Italian ITI Registry, carried out from 1995 to 2015 (last follow-up 2018), 137 primary ITI courses in severe HA patients (90/137 with poor prognosis) were analysed for predictors of outcome (complete/partial response or failure). Sixty-six of them (48%) were prospectively evaluated. RESULTS ITI was successful in 91/137 patients (66.4%) and 70 (51.1%) achieved complete response within 11 months (median). Historical peak titres ≤200 BU/ml (P = .033), inhibitor titres ≤5 BU/ml at ITI start (P = .001), peak titres ≤100 BU/ml during ITI (P

Acquired haemophilia A (AHA) is a rare bleeding disorder due to autoantibodies to coagulation factor VIII that may be secondary to autoimmune diseases, cancer, drugs, pregnancy, infections, or be idiopathic. Recurrent bleeding, often severe, mostly in muscles and soft tissues, and isolated prolonged activated partial thromboplastin time (aPTT), in the absence of personal and family history of bleeding, are typical features that should raise the suspicion of AHA. Poor awareness of the disease results in diagnostic delays and inappropriate treatment.The Italian Association of Haemophilia Centres (AICE) developed consensus recommendations in cooperation with the Italian Society on Thrombosis and Haemostasis (SISET). The document was shared with scientific societies of specialist physicians, laboratory professionals and pharmacists to spread knowledge about AHA and promote appropriate diagnosis/treatment.Ready availability of the aPTT mixing test is crucial, although diagnostic confirmation and optimal management require prompt referral of patients to specialised centres with rapidly available diagnostic and therapeutic facilities. If immediate referral is unfeasible, treatment must be undertaken early, under guidance of specialised centres or based on shared protocols. Recommendations about diagnosis, general management and, in bleeding patients, haemostatic therapy using bypassing agents or replacement treatment, including the recently available recombinant porcine factor VIII, are provided, considering the different clinical settings and laboratory facilities.This consensus document aims to improve the overall healthcare pathways for AHA, harmonise the management and therapeutic approaches to newly diagnosed patients and reduce the still relevant complications and mortality in this setting.

Comprehensive evidence-based guidelines and well-validated assessment scales for pain in people with hemophilia (PwH) are needed. Here, we report 28 statements covering five topics on pain assessment and management in pediatric and adult PwH that were developed by 60 Italian hemophilia specialists during a Delphi consensus process. Overall, a clear consensus was achieved for 19 of the 28 statements. Consensus was reached on all statements on the topic of pain assessment and quality of life (QoL), including the need for regular pain assessment on a quantitative scale, the importance of distinguishing between different pain types, and the need to evaluate the impact of pain on patient QoL. The other four topics concerned acute and chronic pain management in adults and in children. Consensus was reached on statements regarding non-pharmacologic treatment and the use of first-line paracetamol (acetaminophen). There was a lack of consensus regarding the use of non-steroidal anti-inflammatory drugs, cyclooxygenase-2 inhibitors, or opioids.

Hemophilia is associated with a high financial burden on individuals, healthcare systems, and society. The development of inhibitors significantly increases the socioeconomic burden of the diseases. This study aimed to review and describe the burden of hemophilia with inhibitors, providing a reference scenario to assess the impact of new products in the real word. Two systematic literature reviews were performed to collect data on (i) health economics and (ii) health-related quality of life evidences in hemophilic patients with inhibitors. The costs associated with patients with hemophilia and inhibitors are more than 3 times greater than the costs incurred in those without inhibitors, with an annual cost per patient that can be higher than €1 000 000. The costs of bypassing agents account for the large majority of the total healthcare direct costs for hemophilia treatment. The quality of life is more compromised in patients with hemophilia and inhibitors compared to those without inhibitors, in particular the physical domains, whereas mental domains were comparable to that of the general population. The development of an inhibitor has a high impact on costs and quality of life. New treatments have the potential to change positively the management and socioeconomic burden of hemophilia with inhibitors.

Background: Bypassing agents are the first line therapy in patients with acquired haemophilia A (AHA). Activated prothrombin complex concentrate (aPCC) proved to be effective as initial treatment, but 20% of patients (pts) had relapses. aPCC as short-term prophylaxis to reduce subsequent bleeds is still not clear. Aim: To evaluate whether a short-term prophylaxis with low dose of aPCC can reduce bleeding relapses after initial AHA treatment, maintaining safety. Methods: The FAIR Registry is a retrospective-prospective study started on December 2012, that collected data on all pts with AHA treated with aPCC in 12 Italian Haemophilia Centers. All statistical analyses were carried out in the 56 pts included in the registry. Results: 31 retrospective and 25 prospective pts were evaluated.101 bleeds requiring treatment were reported, 84.1% spontaneous, 71.3% involving muscles or skin. Major bleeds were 38,6%. Low-dose aPCC as short-term prophylaxis was started after the first resolved episode in 15/56 pts, 58% of whom prospective, in a mean dose of 54.2 ± 23.0 IU/kg, higher (61.4 ± 23.4 IU/kg) in the prospective group than in the retrospective one (44.3 ± 19.7 IU/kg) and it was continued up to a mean of 20.5 ± 17.6 days, similar in both groups. A total of 32 bleeding relapses were reported, 87.5% in the retrospective group. Only 9.4% occurred during short-term prophylaxis (p < 0.05). In our Registry no thromboembolic events were found. Conclusion: Initial AHA treatment with aPCC proved to be highly effective, but a consecutive low dose as short-term prophylaxis seems to demonstrate a significant reduction in bleeding relapses maintaining safety.

The investigation of mental health among persons with haemophilia is mostly focused on negative and disease-related indicators. Literature however shows that psychosocial resources and optimal daily functioning can co-exist with chronic disease. The Dual Continua Model operationalizes positive mental health as 'flourishing', a condition comprising emotional, psychological, and social well-being dimensions. In the present study physical and mental health were comparatively assessed through positive and negative indicators in adults with haemophilia and a control group. Participants included 84 Italian persons with severe haemophilia (M

Background: The appearance of inhibitors is the most serious complication in haemophilia A (HA) patients. The primary objective is their eradication. Up to date, immune tolerance induction (ITI) was the only therapeutic option to achieve this. Aim: To assess the efficacy of moroctocog-alpha as an ITI regimen in a population of HA patients with high-titre inhibitors. Methods: The REF.IT Registry is a retrospective-prospective study that collected data on all patients with HA and high-titre inhibitors treated with moroctocog-alpha as an ITI regimen at twelve Italian Haemophilia Centres. Results: We enrolled 27 patients, 85.2% were children. All patients were high responders, 88.9% had severe HA. We found 69.3% of them had one or more risk factors for poor ITI prognosis, 14.8% were ITI rescue. Overall 59.3% achieved a complete/partial success (complete in 51.9%). ITI failed in 11 patients, 63.6% of them with poor-prognosis risk factors. Inhibitors appeared after a mean of 27 exposure days. Mean historical peak was 78.8BU/mL. The primary ITIs started on average 20.2months after the diagnosis. A partial or complete success after a mean of 15months of treatment was achieved in 56.6% of the children while the same result was obtained by 75.0% adults after 22months from ITI onset. Patients who were treated with high-dose moroctocog-alpha (200UI/kg/day) were 63.0%. Conclusion: Our Registry showed that the use of moroctocog-alpha in the setting of ITI was effective and safe also in a population of patients with high-titre inhibitors, presenting one or more risk factors for poor ITI prognosis.

The development of neutralizing antibodies (inhibitors) against infused factor VIII currently represents the main complication of replacement therapy in patients with severe hemophilia A. Inhibitors, indeed, particularly high-titer inhibitors (>5 BU/mL), greatly complicate the management of bleeding, exposing patients to an increased morbidity and mortality risk, thus representing a significant burden for physicians of Hemophilia Treatment Centers (HTCs). Although bypassing agents (i.e., activated prothrombin complex concentrate [APCC] and recombinant activated factor VII [rFVIIa]) are available for the treatment and prevention of bleeding in inhibitor patients, their efficacy, safety, and cost–benefit outcomes are poorly known in the long term and should be further improved. In the frame of the update of recommendations for the management of inhibitor patients by the Italian Association of Hemophilia Centers (AICE), to collect more information on real-life therapeutic approaches with bypassing agents in this setting, a survey was conducted among the Directors of the Italian HTCs. From questionnaires returned by 55% of them, data on the use of rFVIIa and APCC in children, adolescent, and adult patients with hemophilia A and inhibitors were obtained and are summarized in this article, including information about the implementation of prophylaxis with both bypassing agents, the adopted regimens, and reasons for starting, adjusting, and interrupting such a therapeutic approach.

Background: The aim of this study was to provide an Italian version of the Haemophilia Activities List (HAL) and check its reliability in Italian medical centers. Methods: The Italian version of this assessment was administered to 80 patients (aged 18-65 years) affected by haemophilia A and B (moderate or severe). The validation was accomplished by comparing it to the revised and expanded Arthritis Impact Measurement Scales (AIMS2). Results: The internal consistency of the Italian version of the HAL had statistically high results: Cronbach's α 0.957-0.579. The highest internal consistency was measured in the domains ‘leg functionality' and in the overall points of the HAL questionnaire. The correlation between the AIMS2, which has been translated into Italian, and the version of the HAL questionnaire that we proposed, yielded good results for the following correlations: AIMS2 all and HAL overall (r = 0.64), AIMS2 physical function and HAL overall (r = 0.66), AIMS2 pain and HAL overall (r = 0.66). Conclusion: The Italian version of the HAL questionnaire presents both internal coherence and convergent validity. It can be used in addition to other functional tests to measure outcomes in moderate and severe haemophiliac diseases or to determine the quality of life as observed in the everyday life of patients.

Analyses of the bleeding tendency by means of the bleeding score (BS) have been proposed until now to confirm diagnosis but not to predict clinical outcomes in patients with inherited von Willebrand disease (VWD). We prospectively followed up, for 1 year, 796 Italian patients with different types of VWD to determine whether the previous BS of European VWD1 is useful to predict the occurrence of spontaneous bleeds severe enough to require replacement therapy with desmopressin (DDAVP) and/or von Willebrand factor (VWF)/factor VIII concentrates. Among the 796 patients included, 75 (9.4%) needed treatment of 232 spontaneous bleeding events. BS10 and VWF:ristocetin cofactor activity10 U/dL were associated with the risk of bleeding, but only a BS10 remained highly associated in a multivariable Cox proportional hazard model (adjusted hazard ratio: 7.27 [95% confidence interval, 3.83-13.83]). Although the bleeding event-free survival was different in VWD types, only a BS10 could predict for each type which patient had bleeding events severe enough to require treatment with DDAVP and/or concentrates. Therefore, BS can be considered a simple predictor of clinical outcomes of VWD and may identify patients needing intensive therapeutic regimens.

Nowadays, patients with hemophilia A receive a high standard of care; therefore, the most challenging complication of factor VIII (FVIII) replacement therapy has become the development of FVIII inhibitors, which render the concentrate infusion ineffective and expose patients to an increased risk of morbidity and mortality. Among environmental risk factors influencing inhibitor development, the type of FVIII products has always drawn the attention of investigators. Conflicting results are reported in the literature concerning rates of inhibitor development after either plasma-derived or recombinant FVIII concentrates. To help elucidate this controversial issue, we have performed a systematic review and meta-analysis of prospective studies evaluating the incidence of inhibitors in previously untreated patients with severe hemophilia A receiving plasma-derived or recombinant FVIII products. The quality of the studies was assessed using the Newcastle-Ottawa Scale (NOS), the STrenghtening the Reporting of OBservational studies in Epidemiology and an ad hoc quality score. Overall, 28 prospective studies, including 1,421 patients with hemophilia A, fulfilled our selection criteria and were included in the systematic review. No statistically significant differences were observed in the inhibitor incidence between plasma-derived and recombinant FVIII concentrates considering all (weighted means: 23%, 95% CI: 15-33% vs. 29%, 95% CI: 26-32%) and high titer (16%, 95% CI: 10-26% vs. 18%, 95% CI: 15-21%) inhibitors. Similarly, no significant differences were found in the inhibitor incidence among the different classes of recombinant products. In conclusion, the results of our meta-analysis show that the different types of FVIII products are not associated with different risks of inhibitor development.

PubMedID: 23731246 Patients with haemophilia A and inhibitors are at high risk for severe bleeding, progression of joint disease and deterioration of health-related quality of life (HRQoL). To determine the impact of prophylaxis with an activated prothrombin complex concentrate (aPCC) on HRQoL, HRQoL was assessed using the Short-Form (SF)-36 Health Survey and the EQ-5D questionnaire in subjects ?14 years participating in a prospective, randomized, crossover study comparing 6 months of aPCC prophylaxis with 6 months of on-demand therapy. Eighteen of 19 patients completed the survey or questionnaire before and after the on-demand therapy and prophylaxis periods. A general trend towards improved HRQoL after prophylaxis was observed for the 18 evaluable patients in all SF-36 dimensions except for vitality/energy and physical functioning. After prophylaxis, 'good responders,' defined as patients experiencing ?50% reduction in bleeding, exhibited statistically and clinically significant differences in the physical component score (P = 0.021), role - physical (P = 0.042), bodily pain (P = 0.015), and social functioning (P = 0.036). Similarly, the EQ-5D health profile showed a trend towards improvement after prophylaxis in all evaluable patients. Among the good responders, improvements did not differ from those observed after on-demand treatment. EQ visual analogue scale values were slightly improved following prophylaxis for all evaluable patients and the EQ-5D utility index improved in the good responders only. During prophylaxis, patients missed significantly fewer days from school or work because of bleeding than during on-demand treatment (P = 0.01). In conclusion, by significantly reducing bleeding frequency in good responders, aPCC prophylaxis improved HRQoL compared with on-demand treatment. © 2013 John Wiley & Sons Ltd.

Randomized and cohort studies have provided evidence confirming the hypothesis, based on in-vitro observations, that the use of very high-purity factor VIII (FVIII) concentrates, either immuoaffinity chromatography purified or produced by recombinant DNA technology, may slow immunological deterioration in human immunodeficiency virus (HIV)-infected haemophiliacs, while high-purity concentrates, produced by ion-exchange chromatography, did not produce a benefit. Even though these data clearly indicate that very high-purity concentrates should be preferred for the replacement therapy of HIV-positive haemophiliacs, there are little data, based on direct comparison, supporting the use of very high-purity concentrates rather than high-purity preparations, which are less expensive. In an attempt to address this issue, we prospectively compared CD4 cell counts and changes of clinical status in 18 HIV-positive haemophiliacs, randomly assigned either to receive the treatment with a very high-purity FVIII concentrate, purified by immunoaffinity chromatography, or a high-purity product, produced by ion-exchange chromatography. All patients had CD4 lymphocyte counts below 300 μL(-1) , were negative for the hepatitis B surface antigen and the HIV p24 antigen, and were receiving antiretroviral treatment with Zidovudine for at least 6 months. There were no significant changes of CD4 cell counts over the 96-week follow-up period or between the two groups. No signficant differences between the two groups were detected in the occurrence of AIDS-defining diagnoses (one in each group). On the whole, no striking benefit is conferred to the immune status of asymptomatic HIV-positive haemophiliacs by using either of these high-purity and very high-purity FVIII concentrates for 96 weeks. Larger prospective randomized trials are needed to establish definitely whether it is necessary to resort to very high-purity concentrates or it is sufficient to use high-purity concentrates to slow the fall of CD4 cell counts that occurs in HIV-positive haemophiliacs. Randomized trials, based on clinical end-points, are also needed to demonstrate whether slowing the fall in CD4 cells results in clinical benefits, delaying the occurrence of AIDS.

Intracranial haemorrhage (ICH) is the most serious bleeding symptom in haemophiliacs, resulting in high rates of mortality and disabling sequelae. The Association of Italian Haemophilia Centres carried out a retrospective survey (1987-2008) of ICH occurring in haemophiliacs with the goals to establish: (i) incidence, location of bleeding, death rate and disabling sequels; (ii) risk factors for ICH; and (iii) treatment used during the acute phase of ICH and for recurrence prevention. A total of 112 ICH episodes had occurred in 88 patients (78 haemophilia A, 10 haemophilia B), 24 of whom experienced recurrences. The cumulative hazard of ICH for the whole cohort over the entire follow-up period was 26.7 per 1000 patients, and the annualized rate of ICH was 2.50 events per 1000 patients (95% CI 1.90-3.31). The risk of ICH was higher in the youngest children (24.4 per 1000, 95% CI 12.7-47.0 in the first year of age and 14.9, 95% CI 7.1-31.4 in the second year of age) and then progressively rose again after the age of 40. Univariate, bivariate (age-adjusted) and multivariate analysis investigating the effects of patient characteristics on ICH occurrence showed that haemophilia severity and inhibitor status were strongly associated with ICH [severe vs. mild, HR 3.96 (2.39-6.57); inhibitor vs. non-inhibitor 2.52 (1.46-4.35)]. HCV infection was also associated with the risk of ICH [HR 1.83 (1.25-2.69)]. Therapeutic suggestions based upon our experience to control ICH recurrence are provided.

Haemophilia A (HA) is an X-linked recessive haemorrhagic disorder caused by a deficiency of coagulation factor VIII. Disease causative mutations are heterogeneous and spread all over the F8 gene sequence, with the exception of intron 22 inversion occurring in about 50% of severe patients. To define the specific mutational repertoire and mutation detection rate, we analysed F8 gene, by polymerase chain reaction and direct sequencing, in 128 unrelated patients from Southern Italy with severe (n = 108), moderate (n = 9) or mild (n = 11) HA. We identified 120 mutations, including 64 cases of intron 22 inversion (53.3%), three of intron 1 inversion (2.5%), one large deletion (0,8%) and 52 point mutations (43.3%). In particular, 19/120 were novel and 7/52 point mutations (13.5%) occurred at CpG sites. We also investigated eight prothrombotic genetic variants in a subgroup of 74 severe HA patients to evaluate their possible protective effect on the severity of clinical expression. Methylenetetrahydrofolate reductase A1298C and plasminogen activator inhibitor-1 4G variants recurred more frequently in HA patients with a less-severe phenotype. Clinical impact of these findings needs large-scale studies to further define the role of these prothrombotic variants as possible modifier factors of HA phenotype.

Hepatocellular carcinoma (HCC) is an increasingly frequent cause of mortality in hemophiliacs with chronic viral hepatitis. Early diagnosis of the tumor at an initial stage is known to improve the outcome of HCC treatment. Because all HCC cases detected in a previous study based upon annual ultrasound (US) surveillance of hemophiliacs with elevated alanine aminotransferase levels were multinodular, this study was designed to evaluate if a more intense surveillance with US and alphafetoprotein (AFP) serum levels of all the patients infected with the hepatitis C virus (HCV) improved the identification of single nodule tumors. A multicenter cohort of 559 HCV-infected hemophiliacs was divided into 2 arms, one followed up at 6-month intervals and one at 12-month intervals depending on the choice and available facilities of each treatment center. During a 6-year surveillance period, HCC was diagnosed in 5 (2.4%) of 210 patients in the 6-month group and in 3 (0.9%) of 349 patients in the 12-month group. The overall incidence rate of HCC was 239 per 100 000 per year (397 per 100 000 per year in the 6-month group and 143 per 100 000 per year in the 12-month group; differences not statistically significant). By multivariate analysis, HCC risk was increased 12.9-fold with alcohol intake more than 80 g/d and 15.2-fold with AFP levels higher than 11 ng/mL. Liver-related death occurred in 8 cases (1.4%), including 3 with HCC. Still alive and tumor free after 24 to 34 months from diagnosis are 3 patients with multinodular tumors treated with repeat chemoembolization followed by orthotopic liver transplantation. In conclusion, 6-month surveillance with US did not increase the chances of detection of single nodule tumors, but it is reasonable to assume that successful treatment of multinodular tumors based upon debulking with chemoembolization and liver transplantation was facilitated by this approach. (Blood. 2003;102:78-82)

In a multinational working group, an instrument (Haemo-QoL) to assess quality of life in children/adolescents with haemophilia and their parents has been developed. In co-operation with haemophilia treatment centres in six European countries, approximately 10 children/adolescents with haemophilia per country and their parents were asked to participate in the pilot-testing. Both self-reported and parent-reported questionnaires were provided for two age-groups of children (4-16 years). Medical data was collected from physicians from patient files. Answers to open questions from participants (58 children and 57 parents) confirmed the content of 116 of the preliminary items. Cognitive debriefing revealed that the majority of the Haemo-QoL was rated favourably, but 29 questions were recommended to be omitted and several items to be reformulated. Preliminary psychometric testing of the revised 77 item questionnaire in the same sample showed acceptable reliability and validity, which will be examined in a subsequent study with a larger patient sample.

The development of alloantibodies neutralising therapeutically administered factor (F) VIII/IX (inhibitors) is currently the most severe complication of the treatment of haemophilia. When persistent and at a high titre, inhibitors preclude the standard replacement treatment with FVIII/FIX concentrates, making patients’ management challenging. Indeed, the efficacy of bypassing agents, i.e., activated prothrombin complex concentrates (aPCC) and recombinant activated factor VII (rFVIIa), needed to overcome the haemostatic interference of the inhibitor, is not comparable to that of factor concentrates. In addition, the therapeutical response is unpredictable, with a relevant inter-individual and even intra-individual variability, and no laboratory assay is validated to monitor the efficacy and safety of the treatment. As a result, inhibitor patients have a worse joint status and quality of life compared to inhibitor-free subjects and the eradication of the inhibitor by immune tolerance induction is the preeminent therapeutic goal, particularly in children. However, over the last decades, treatment with bypassing agents has been optimised, allowing home treatment and the individualisation of regimens aimed at improving clinical outcomes. In this respect, a growing body of evidence supports the efficacy of prophylaxis with both bypassing agents in reducing bleeding rates and improving the quality of life, although the impact on long-term outcomes (in particular on preventing/reducing joint deterioration) is still unknown. This review offers an update on the current knowledge and practice of the use of bypassing agents in haemophiliacs with inhibitors, as well as on debated issues and unmet needs in this challenging setting.

Although current treatment guidelines recommend prophylaxis in paediatric patients with haemophilia, specific indications for and barriers to the prescription of prophylaxis in the paediatric haemophiliac population have not been established. The aim of this web-based survey of clinicians at Haemophilia Treatment Centres in Italy was to identify factors for and against the initiation of prophylactic coagulation factor replacement therapy in paediatric patients with haemophilia.A literature search was conducted to identify factors to include in the survey. Seventeen clinicians from Italian Haemophilia Centres were invited to complete the web-based survey and to rank factors in favour of and those that acted as barriers to prophylaxis in terms of "importance" and "influence" on a numerical scale (0=not important to 100=very important). Any factors for which there was a large discrepancy in results from the survey were further "ranked" by clinicians at an interactive question and answer session at a symposium.A total of 13 web surveys were returned; the most highly scored factors favouring prophylaxis were "bleeding frequency", "bleeding severity" and "presence of target joints", and the most highly scored barriers were "parents' acceptance", "venous access" and "compliance to therapy". Other important factors favouring prophylaxis were "severity of coagulation defect" and "orthopaedic score".This survey gives helpful clinician-derived information for people treating haemophiliacs in Italy, to help the treatment-providers orient themselves better regarding the prescription of prophylaxis for paediatric patients.

SummaryA multicenter prospective study of recombinant activated factor VII (rFVIIa) given by continuous infusion (CI) to treat severe hemorrhages and to handle surgical procedures was carried out.Relations between clinical efficacy, dosages used and levels of FVII coagulant activity (FVII:C) achieved in plasma were also evaluated. Case material included 25 patients with hemophilia (9 children and 16 adults) with high-responding inhibitors and 3 patients with acquired factor VIII inhibitors. Overall, 35 CI courses were given for 10 spontaneous bleeding episodes, 11 major surgical procedures and 14 minor surgical procedures. Bolus doses of 90 to 150 μg/kg (median: 100) were followed by CI given at median rates of 20 μg/kg/h for major surgery and of 17 and 16 μg/kg/h for minor surgery and spontaneous hemorrhages. Satisfactory hemostasis was obtained in 30 of 35 courses (88%). rFVIIa CI was ineffective in 2 hemophiliacs undergoing surgical operations and in another hemophiliac with hemoperitoneum who had to be switched to other treatments (high doses of porcine or human factor VIII concentrates). rFVIIa CI was partially effective in 2 hemophiliacs who had mild local bleeding after minor surgery. The CI rates and the corresponding FVII:C levels in plasma were similar in effective, partially effective and ineffective courses (median rate: 17, 20 and 20 μg/kg/h, respectively; median FVII:C: 14, 18 and 18 IU/ml, respectively). A single adverse event was observed, superficial thrombophlebitis. This study confirms that rFVIIa given by CI is effective in a high proportion of patients with factor VIII inhibitors. It also demonstrates that FVII:C levels attained in plasma do not always predict efficacy because similarly high levels were attained during successful treatments and in those that failed.

SummaryProthrombin deficiency is an autosomal recessive disorder associated with a moderately severe bleeding tendency. In this study, 13 patients with prothrombin deficiency were screened for the presence of alterations in the prothrombin gene, and nine novel candidate mutations were identified. Of 11 patients with hypoprothrombinemia, ten are homozygous for five mutations and one patient is a compound heterozygote. The two patients with dysprothrombinemia are homozygous for two mutations. Eight of nine mutations are missense ones associated with single amino acid substitutions in the propeptide (Arg-1Gln, Arg-2Trp), the kringle-1 (Asp118Try) and kringle-2 (Arg220Cys) domains and the catalytic serine protease domain (Gly330Ser, Ser354Arg, Arg382His and Arg538Cys). The ninth mutation is an in-frame deletion of 3 bp that results in the omission of one amino acid (del Lys 301/302). The combination of these missense mutations with crystal structures for α-thrombin and the prothrombin fragments 1 and 2 resulted in new insight into the function of α-thrombin. The hypoprothrombinemia mutations were inferred to affect either the cleavage of the propeptide from the Gla domain, the stability of the kringle-1 and −2 domains, or the close association of the A and B chains of the serine protease domain. The dysprothrombinemia mutations were inferred to directly affect catalytic function through their location at the active site crevice or exosite 1 within the serine protease domain.

Summary This article describes prenatal diagnosis (PND) of haemophilia B (HB) within the framework of Italian haemophilia centres and genetics laboratories. The study details the experience from six haemophilia genetic centres (three in the North, one in the Centre and two in the South of Italy) and summarizes the different techniques used to perform PND of HB during the last 15 years. To date, the Italian HB database includes 373 characterized unrelated patients and their genetic information has permitted the identification of 274 carriers of childbearing age. This database represents the main instrument for timely and precise PND. Sixty-six prenatal diagnoses were performed on 52 HB carriers whose average age at the time was 34 (ranging from 24 to 44 years). In 44 cases, genetic counselling for carrier status determination was performed before pregnancy, while eight were not studied prior to pregnancy. Foetal samples were obtained by chorionic villus sampling in 52 cases, by amniocentesis in 12 while two were diagnosed by analysis of free foetal DNA obtained from maternal peripheral blood. In 35 (53%) pregnancies the foetus was female. For 31 men (47%), haemophilia status was determined by analysis of previously determined informative markers or familial mutations (12 affected and 19 unaffected). There may be more than one laboratory involved in the PND diagnostic pathway (providing DNA extraction, karyotype analysis, gender determination, maternal contamination detection, molecular diagnosis and sequencing). Good communication between all the parties, coordinated by the haemophilia centre, is essential for a successful and rapid process.

Introduction: Data on APCC´s effectiveness, safety and quality of life are relatively poor because of the rarity of patients with FVIII or FIX inhibitors, the small populations included in clinical trials and the relatively short follow-up available. The FEIBA-GO study was designed to capture long-term outcomes on effectiveness, safety and health-related quality of life (HR-QoL) in subjects receiving APCC in different settings in routine clinical practice. Primary objective is to describe the hemostatic effectiveness of APCC in different settings (prophylaxis and on demand, including patients on immune tolerance induction); most relevant secondary objectives aim at describing joint functionality outcomes, safety, HR-QoL, daily activity level, acute and chronic pain associated with hemophilia, as well as healthcare resources used. Methods: The study is a prospective, non-interventional, multicenter cohort study in patients with hemophilia A or B and high-responding inhibitors treated with APCC. A hundred subjects are targeted for enrollment; treatment regimens are at the discretion of the attending physicians in accordance with routine clinical practice, either on early, secondary or tertiary prophylaxis or on demand, including patients treated with APCC during immune tolerance induction. The observation period per subject will be 4 years. Results: As of June 1, 2016, 40 centres have been qualified in 14 countries and 16 centres have been initiated. 27 patients have been enrolled at 14 open sites in 7 countries. Demographic data are available for the 27 patients enrolled so far and are presented for the first time. All patients have severe hemophilia A: 23 are caucasian, 1 african (3 missing). At the enrolment, 18 of them were on prophylaxis and 6 treated on demand (3 missing). Overall median age is 19 years (min-max: 3-71), 17.5 years in patients on prophylaxis (min-max: 3-71) and 39.5 years in patients on demand (min-max: 22-65). Overall median inhibitor titer at enrolment was 8 BU (min-max: 1-2410), 8 BU for prophylaxis (min-max: 1-92) and 12 BU in patients on demand (min-max: 3-35). Nijmegen modified Bethesda assay was used in 18 centres, while 4 used non-modified Nijmegen Bethesda assay (5 missing). Six subjects (3 on prophylaxis, 2 on demand and 1 unknown) have been reported to have overall 13 target joints. Assessment for acute pain was performed in 12 patients and for chronic pain in 9 patients. Two of 12 patients assessed reported acute pain (both on demand). Two of the 9 patients in whom the assessment was performed reported chronic pain (treatment regimen missing). For one patient, information is not available and for another one it has been reported that pain assessment is not routine examination. Gilbert Score was assessed in 6 patients at screening. Discussion/Conclusion: This study will further enhance the information on long-term effectiveness, HR-QoL and safety of APCC across and beyond Europe in the real world on hemophilia A and B patients with high-responding inhibitors under a variety of prescribing regimens in routine clinical practice. Disclosures Cid: Baxalta Innovations GmbH, now part of Shire: Other: Investigator Clinical Studies. Escuriola:Baxalta, now part of Shire: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Investigator Clinical Studies, Research Funding; Bayer: Consultancy, Honoraria, Research Funding; Biotest: Consultancy, Honoraria, Research Funding; CSL Behring: Consultancy, Honoraria, Research Funding; Grifols: Consultancy, Honoraria, Research Funding; Octapharma: Consultancy, Honoraria, Research Funding; NovoNordisk: Consultancy, Honoraria, Research Funding. Hermans:Baxalta, now part of Shire: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Investigator Clinical Studies. Holme:Baxalta, now part of Shire: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Investigator Clinical Studies. Negrier:LFB: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees, Other: Travel support; SOBI: Membership on an entity's Board of Directors or advisory committees; Octapharma: Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Baxter: Membership on an entity's Board of Directors or advisory committees; Pfizer: Research Funding; Alnylam: Research Funding; CSL Behring: Membership on an entity's Board of Directors or advisory committees, Research Funding; NovoNordisk: Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding. Rangarajan:Baxter: Research Funding; Grifols: Consultancy, Research Funding; Biogen: Consultancy; Pfizer: Research Funding; Baxalta, now part of Shire: Other: Investigator Clinical Studies, Research Funding; Novo Nordisk: Research Funding; Biotest: Research Funding. Rocino:Baxalta, now part of Shire: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Investigator Clinical Studies; Bayer: Honoraria, Membership on an entity's Board of Directors or advisory committees; NovoNordisk: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; CSL Behring: Consultancy, Honoraria; Kedrion: Consultancy, Honoraria; Sobi: Consultancy, Honoraria. Windyga:Octapharma: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Alexion: Other: Speaker's honorarium; Biogen: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Sanofi: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; CSL Behring: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Aspen: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Nordisk: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Baxalta, now part of Shire: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Investigator Clinical Studies, Patents & Royalties, Research Funding, Speakers Bureau. Gringeri:Shire: Employment, Equity Ownership. Crea:Shire: Employment, Equity Ownership.

Summary. Background: Inhibitor development is influenced by several factors and the type of factor VIII (FVIII) products may play a role. Objectives: In order to explore such a role, we designed a cohort study whose novelty resides in the classification of products not only according to the source of FVIII (plasmatic, pd, or recombinant, r) but also to their degree of purity (expressed as specific activity). Patients/Methods: Treatment data up to inhibitor development or 150 exposure days were collected in 377 patients with hemophilia A. Results: Inhibitors developed in 111 patients (29%; 96 high-responders, 25%). The cumulative incidence was progressively higher from patients treated with low/intermediate-purity pdFVIII compared with those treated with high-purity pd and rFVIII. The adjusted hazard ratio of inhibitor development was 4.9 with rFVIII and 2.0 with high-purity pdFVIII (95% CI, 2.9–8.3 and 1.1–4.0), taking as reference low/intermediate-purity pdFVIII. There was no difference in the frequency of inhibitor testing between treatment groups. Sensitivity analyses (in patients who never switched product type, previously untreated patients, those treated on-demand and those with high-risk F8 mutations) confirmed an increased inhibitor risk with rFVIII and high-purity pdFVIII. Conclusions: This study shows that the degree of purity of FVIII products influences inhibitor development independently from other risk factors, and emphasizes that differences exist within pdFVIII products.

SummaryVery-high-purity Factor VIII concentrates produced by monoclonal or recombinant technology have been postulated to be more antigenic resulting in an increased risk of inhibitor development in hemophilia A patients. However, previous reports, mainly based on prevalence figures, may have understimated the “true” risk of this complication in patients treated with less pure Factor VIII concentrates. The present study, started in 1975, has been designed to calculate the risk of inhibitor development in patients with severe or moderate hemophilia A, followed since their first exposure to intermediate or high-purity Factor VIII concentrates, produced by conventional technologies. Sixty-four hemophiliacs fulfilled the enrollment criteria. Inhibitors developed in 20.3% (13/64) of all patients and in 23% (11/48) of those with severe Factor VIII deficiency. Eleven patients manifested a strong anamnestic response after exposure to Factor VIII (high responders) and 2 had low inhibitor concenlialions despite repeated Factor Vlll infusions (low responders). The incidence of inhibitor development was 24.6 per 1000 patient yeuis of observalion. The, cumulative! risk of inhibitor formation was 19,9% at age of 6 years, and 20.3% at 5 years after the first exposure. The risk was 19.3% at 70 days of exposure to Factor VIII concentrates, and 17.2% after a total of 50,000 units of Factor VIII given.Further stuides are needed to confirm the above risk of acquiring an inhibitor, which indicates and under-estimations by previous studies. In addition, more data is needed to demonstrate whether very high purity Factor VIII concentrates may be more antigenie than conventional preparations.

Von Willebrand disease (VWD) is the most common inherited bleeding disorder and is due to quantitative and/or qualitative defects of von Willebrand factor (VWF). Despite the improved knowledge of the disease, detailed data on VWD types requiring specific treatments have not been reported thus far. To determine the number and types of VWD requiring therapy with desmopressin (DDAVP) and/or VWF/FVIII concentrates in Italy, a national registry on VWD (RENAWI) was organized. Only 16 of 48 centers included VWD in the RENAWI with diagnoses performed locally. Patients with uncertain results were retested by two expert laboratories using multimeric analysis and mutations of the VWF gene. A total of 1234 of 1529 (81%) cases satisfied the inclusion criteria and could be classified as VWD1 (63%), VWD2A (7%), VWD2B (6%), VWD2M (18%), VWD2N (1%), and VWD3 (5%). VWD types were also confirmed by DNA analyses and occur in young adults (83%), mainly in women (58%). Mucosal bleedings (32 to 57%) are more frequent than hematomas (13%) or hemarthrosis (6%). Most patients were exposed to an infusion trial with desmopressin (DDAVP) and found responsive with the following rates: VWD1 (69%), VWD2A (26%), VWD2M (29%), and VWD2N (71%). However, DDAVP was not always used to manage bleeding in all responsive patients and VWF/FVIII concentrates were given instead of or together with DDAVP in VWD1 (30%), VWD2A (84%), VWD2B (62%), VWD2M (63%), VWD2N (30%), and VWD3 (91%). Data of the RENAWI showed that correct VWD identification and classification might be difficult in many Italian centers. Therefore, evidence-based studies should be organized only in well-characterized patients tested by laboratories that are expert in the clinical, laboratory, and molecular markers of VWD.

Abstract 3494 Poster Board III-431 Background von Willebrand disease type 3 (VWD3) is due to virtually complete deficiency of the von Willebrand factor (VWF) and, for this reason, has been also described as “severe VWD”. Although rare (1-5 cases per million population), VWD3 is of major interest because of its severe clinical presentation, the need for replacement therapy with VWF/FVIII concentrates and the risk of occurrence of anti-VWF inhibitors after the infusion of VWF/FVIII concentrates. Aims and design of the study to determine the prevalence and determinants of bleedings requiring therapy with VWF/FVIII concentrates in VWD3 patients, data were collected from the Italian registry on Hemophilia and Allied Disorders organized on behalf of the Italian Association of Hemophilia Centers (AICE). The VWD3 patients included in the registry were then followed up for one year by six Italian Centers and prospective data on number, type and management of bleeding episodes were analyzed. Methods VWD3 patients were diagnosed when VWF antigen was undetectable and factor VIII (FVIII) levels were reduced in plasma. Bleeding severity score (BSS) was calculated at enrollment. Gene deletions and mutations were searched for in all available DNA. Bleeding-free survival was computed with the Kaplan-Meier method and a Cox's proportional hazard model was used to calculate the risk of bleeding (hazard ratio = HR) Results In the Italian registry, 105 VWD3 patients (5.7%) were identified among the 1850 VWD (Italian prevalence=1.75 per million). The entire cohort of VWD3 was characterized by the following demographic, clinical and laboratory parameters (median, range): gender (M/F)= 50/55; age=37 (3-65); BSS=18 (3-35); FVIII= 4 (2-18); anti-VWF inhibitors= 7 cases (6.7%) from 3 families. Molecular diagnosis was available in 65/105 cases with the following gene defects (pt-n): large deletion (7); small deletions and insertions (23); nonsense (9); splice site (8) and missense mutations (17). Mucosal bleedings (64%) were more frequent than hematomas and hemarthrosis (24%). At the time of the enrollment in the registry 95/105 (91%) VWD3 had been already exposed to VWF/FVIII concentrates because of bleeding and/or minor or major surgeries. In the prospective study, 52 VWD3 patients could be enrolled and 46 (88%) were treated in a year for 118 bleeding episodes and 27 minor or major surgeries. BSS>10 (6.8, 3.8-12.3) and FVIII 89% (BSS=5-10&FVIII>10U/dL); 64%(BSS>10&FVIII=5-10U/dL); 59% (BSS=5-10&FVIII10&FVIII Conclusions these retro/prospective studies performed for the first time in a relative large cohort of patients show that also VWD3 can be very heterogeneous. BSS & FVIII levels are good predictors of bleeding. Larger multicenter studies should be organized to identify possible additional modifiers influencing the risk of bleeding in VWD3. Disclosures: No relevant conflicts of interest to declare.

Pathophysiologic considerations as well as non-comparative clinical results suggest that very high purity concentrates may slow immunologic deterioration in human immunodeficiency virus (HIV)-infected hemophiliacs. In an attempt to evaluate this hypothesis, we prospectively compared CD4 cell counts, skin testing responses, and changes of the clinical status in 20 asymptomatic HIV-positive hemophiliacs, randomly assigned to continue the treatment with an intermediate purity concentrate or to receive a very high purity product, purified by immunoaffinity chromatography with monoclonal antibodies. In the group switched to the very high purity concentrate there was no significant change of the CD4 cell counts over the 96-week follow-up period, whereas in the group continued on the intermediate purity concentrate, a highly significant decline was detected (P less than .013). Furthermore, in the very high purity group, four of six anergic patients at entry acquired reactivity to skin testing. The results of this study clearly support the use of very high purity concentrates for the replacement therapy of HIV-infected hemophiliacs.

Haemophilia A is the most common inherited bleeding disorder caused by defects in the F8C gene that encodes coagulation factor VIII. This X-linked recessive disorder occurs in approximately 1:5000 males. Haemophilia A is diagnosed based on normal pro-thrombin time, altered activated partial thromboplastin time and reduced factor VIII activity in plasma. Carrier females are usually asymptomatic and can be identified only by molecular analysis. The most frequent mutations in F8C are intron 22 and 1 inversions, which occur in approximately 50% and 5% of patients, respectively, with a severe phenotype. Large gene deletions are observed in approximately 5% of alleles from patients with severe haemophilia A. The remaining severe cases and all moderate and mild cases result from numerous point mutations and small insertions/deletions, which are de novo mutations in one-third of cases. Thus, molecular diagnosis of carrier status and prenatal diagnosis in families without intron 22 or 1 inversions is based on scanning techniques or gene sequencing. When the disease-causing mutation cannot be identified, molecular diagnosis is performed by linkage analysis of several DNA polymorphic markers linked to F8C. Given the clinical heterogeneity among haemophilic patients, many groups, including our own, have examined the relationships between prothrombotic gene variants and haemophilic phenotype to investigate whether prothrombotic gene variants modify clinical expression of the disease.

Immune tolerance induction (ITI) eradicates inhibitors in patients with hemophilia A. This study was designed to investigate the success rate of ITI in high-responding inhibitor patients with severe hemophilia A using recombinant factor VIII (rFVIII). Twenty-six patients received different ITI regimens until a normal recovery (66%) and half-life (6 h) of infused FVIII was achieved. In order to maximize the chance of success, the initiation of ITI was deferred in the majority of patients until the inhibitor declined to10 BU. Twenty-two patients (85%) had baseline inhibitor levels10 BU (median 2.3 BU) when ITI began. Within a median of 6 months, immune tolerance was achieved in 19 of 26 patients (73%) including 12/17 (70%) with intron 22 inversion, 5/7 (71%) with other null mutations and two with small deletion/insertions in the F8 gene. In conclusion, recombinant FVIII induces a high rate of immune tolerance even in carriers of null F8 mutations.

Summary. Aim: A multicenter randomized open-label crossover prospective trial was designed to compare the efficacy, safety, and cost of standard and high dosages of recombinant factor VIIa (rFVIIa) for home treatment of hemarthroses in hemophiliacs with inhibitors. Methods: Patients were instructed to treat, within 6 h from the onset of bleeding, four consecutive hemarthroses of ankles, knees, or elbows, either with the rFVIIa standard dose of 90 μg kg−1 (repeated as necessary every 3 h) or with a single high dose of 270 μg kg−1. Patients who did not achieve a clinical success within 9 h continued rFVIIa treatment with repeated standard doses. Response to treatment was assessed for up to 48 h by patients/caregivers, who reported on a Visual Analogue Scale (VAS) graded from 0 to 100 the improvement in symptoms and also rated the responses as effective, partially effective or ineffective. Success was defined a treatment course rated as effective and with a VAS score ≥70 and failure a treatment course rated as ineffective and VAS score ≤30, whereas treatment courses that did not fulfill these criteria were considered partial responses. Results: Twenty hemophiliacs with inhibitors were originally enrolled (median age: 27 years), 18 of them treated 32 hemarthroses assigned to the standard-dosage and 36 to the high-dosage regimen, during the study period of 18 months. Forty-eight hemarthroses (71%) occurred in target joints. Success rates for standard- and high-dosage regimens were similar: 31% and 25% at 9 h, 53% and 50% at 24 h, 66% and 64% at 48 h, the end point for outcome assessment. The median number of rFVIIa infusions needed to achieve a successful course was significantly greater for the standard-dosage (n = 3) than for the high-dosage regimen (n = 1), and the median amount of rFVIIa ultimately used per successful course was identical (270 μg kg−1). Conclusion: Our results indicate that a high-dosage regimen with rFVIIa for home treatment of hemarthroses is effective, safe, does not imply an increased consumption of rFVIIa and requires the infusion of a smaller number of rFVIIa doses. Its convenience is particularly relevant in cases with difficult venous access and in hemorrhages into target joints.

Thanks to its typical expression, haemophilia can be identified in writings from the second century AD. Haemophilia B, an X-linked recessive bleeding disorder due to factor IX (FIX) deficiency, has an incidence of about 1:30,000 live male births. The factor 9 (F9) gene was mapped in 1984 on Xq27.1. Haemophilia is diagnosed from prothrombin time, activated partial thromboplastin time, and FIX levels. Carrier females are usually asymptomatic and must be identified only with molecular analysis. Linkage analysis of F9 polymorphisms is rapid and inexpensive but limited by non-informative families, recombinant events, and the high incidence of germline mutations; thus, various procedures have been used for the direct scan of F9 mutations. We set up a novel denaturing high performance liquid chromatographic procedure to scan the F9 gene. This rapid, reproducible procedure detected F9 mutations in 100% of a preliminary cohort of 18 haemophilia B patients. Parallel to the development of more efficient diagnostic tools, the life expectancy and reproductive fitness of haemophilic patients have greatly improved and will continue to improve thanks to the use of less immunogenic recombinant FIX. Hopefully, new approaches based on gene therapy now being evaluated in clinical trials will revolutionise haemophilia B treatment.

SummaryHepatitis A vaccination has been recommended to patients with hemophilia since they are exposed to potentially infectious clotting factor concentrates. Aim of this study was to assess the immunogenicity of vaccination in hemophiliacs, infected or not with the human immunodeficiency virus (HIV). A formalin-inactivated hepatitis A vaccine was injected subcutaneously to 113 susceptible adults and children and repeated after 1 and 6 months. 47 vaccinees were anti-HIV positive (28 asymptomatic, 15 with CD4 cell counts of less than 200/pl and 4 with symptomatic disease). The first dose of vaccine induced seroconversion, with antibody titers of at least 20 mlU/ml, in 89% of the 66 anti-HIV negative patients, 100% of them responding after the second injection. In anti-HIV positive hemophiliacs seroconversion rates and antibody titers were significantly lower than in non-infected patients. After 12 months, only 76% of anti-HIV positive vaccinees and 40% of those with signs of HIV disease progression maintained the antibody, whereas all anti-HIV negative patients had titers of 20 mlU/ml or more. Our results indicate that there is an association between defective response to hepatitis A vaccine and stage of progression of HIV disease.

Two cross-reacting material–positive (CRM+) factor VII (FVII) mutations, associated with similar reductions in coagulant activity (2.5%) but with mild to asymptomatic (Gly331Ser, c184 [in chymotrypsin numbering]) or severe (Gly283Ser, c140) hemorrhagic phenotypes, were investigated. The affected glycines belong to structurally conserved regions in the c184 through c193 and c140s activation domain loops, respectively. The natural mutants 331Ser-FVII and 283Ser-FVII were expressed, and in addition 331Ala-FVII and 283Ala-FVII were expressed because 3 functional serine-proteases bear alanine at these positions. The 331Ser-FVII, present in several asymptomatic subjects, showed detectable factor Xa generation activity in patient plasma (0.7% ± 0.2%) and in reconstituted system with the recombinant molecules (2.7% ± 1.1%). The reduced activity of recombinant 283Ala-FVII (7.2% ± 2.2%) indicates that the full function of FVII requires glycine at this position, and the undetectable activity of 283Ser-FVII suggests that the oxydrile group of Ser283 participates in causing severe CRM+ deficiency. Furthermore, in a plasma system with limiting thromboplastin concentration, 283Ser-FVII inhibited wild-type FVIIa activity in a dose-dependent manner.

Inhibitor antibodies to transfused factor VIII pose significant challenges in the management of haemophilia A patients. The main concern is the inefficacy of replacement therapy in patients with high-titre antibodies, who have a shorter life-span and a greater morbidity compared to subjects without inhibitors. The ultimate goal in treating these patients is to eliminate the inhibitor antibody entirely, allowing the recommencement of specific replacement therapy. The results of an immune tolerance regimen based on pharmacokinetic parameters are reported here. In 12 high-responder haemophilia A patients immune tolerance induction (ITI) was attempted with daily administration of factor VIII concentrates of very high purity, either plasma-derived or produced by recombinant-DNA technology. Patients were given 100 IU kg(-1) day(-1) until the inhibitor was shown to be absent by at least two negative assays 1 month apart, with normal recovery of infused factor VIII and normal half-life (> 6 h), as assessed after a 3-day washout period. After the patient was judged to be inhibitor-free, immune tolerance treatment was continued with unmodified factor VIII doses for 2 months. Doses were thereafter gradually reduced and finally, regular prophylaxis by administration of 25 IU kg(-1) three times weekly was instituted. Immune tolerance was achieved in 10 of the 12 patients (including six of seven with long-standing inhibitors) within a median time of 8 months. Outcome of immune tolerance was not influenced by age at start of ITI nor by the interval between inhibitor development and ITI. The success rate and the inhibitor disappearance time of our immune tolerance regimen, utilizing high-purity factor VIII, agrees with those reported by other investigators.

Very high purity factor VIII (FVIII) concentrates (plasma-derived or produced by recombinant-DNA technology) were used to achieve immune tolerance in five patients with high-responding inhibitors to FVIII. The mean time required for inhibitor disappearance was 5 months. Four out of five patients showed normalisation of the half-life of infused FVIII after 8-18 months of treatment with 100 IU FVIII/kg body weight administered once daily. Highly purified FVIII products thus appear to be suitable for achieving immune tolerance without negative effects on endogenous von Willebrand factor levels and activity.

Abstract 25 Background: Inhibitor development is influenced by several genetic and environmental factors and the type of factor VIII (FVIII) products may play a role. Methods: We designed a cohort study whose novelty resides in the classification of products not only according to the plasmatic (pdFVIII) or recombinant (rFVIII) source of FVIII but also to the degree of purity expressed as FVIII specific activity per mg of protein. The role of FVIII product as risk factor for inhibitor development was evaluated in a multivariate model adjusting for potential confounders (i.e. age at first FVIII exposure, intensive treatment and prophylaxis). Cumulative incidences of all and high-responding inhibitors were calculated for the whole cohort of 721 patients with severe and moderate hemophilia A followed-up in 3 Italian Hemophilia Centers. Detailed treatment data from the first FVIII infusion up to inhibitor development or 150 exposure days were available for 377 patients and in this group of patients risk factors for inhibitor development including the type of FVIII product and its degree of purity (i.e. low/intermediate-, high-purity pdFVIII and rFVIII) were analysed. Results: The overall cumulative incidence of inhibitors was 22% (n=160; 130 high-responders, 18%) and it was lower in patients first treated with pdFVIII (107/586, 18%) than in those treated with rFVIII (53/135, 39%). Similar results were obtained by evaluating only high-responding inhibitors and patients with severe hemophilia. The adjusted hazard ratio of inhibitor development was 4.9 with rFVIII and 2.0 with high-purity pdFVIII (95%CI: 2.9–8.3 and 1.1–4.0), taking as reference low/intermediate-purity pdFVIII. There was no difference in the frequency of inhibitor testing between treatment groups. Sensitivity analyses - in patients who never switched product type, previously untreated patients, those treated on-demand and those with high-risk F8 mutations - confirmed an increased inhibitor risk in patients first treated with rFVIII or high-purity pdFVIII than in those treated with low/intermediate-purity pdFVIII. In fact, in all the aforementioned subgroups by multivariate analysis the risk of inhibitor development was invariably 3- to 6-fold higher in patients first treated with rFVIII than in those first treated with pdFVIII, and similar results were obtained for both all inhibitors and high-responding inhibitors. Conclusions: This study shows that the degree of purity of FVIII products influences inhibitor development independently from other risk factors, and emphasizes that differences exist also within pdFVIII products. Disclosures: No relevant conflicts of interest to declare.