Roseline d'Oiron | Paris Sud XI University (original) (raw)

Papers by Roseline d'Oiron

Haemophilia : the official journal of the World Federation of Hemophilia, 2012

The Malignancy in Haemophilia Workshop Group convened a consensus working group of haematologists... more The Malignancy in Haemophilia Workshop Group convened a consensus working group of haematologists and oncologists to review topics related to malignancy in haemophilia. The treatment of malignant disease in this population is increasingly relevant as both outcome and lifespan continue to improve. Although adequate guidance exists for control of spontaneous bleeding episodes and of haemostasis in general surgery, information for management of haemostasis in patients with various malignancies is sparse. To date, no clinical guidelines exist for management of complex bleeding problems, diagnosis, therapy and follow-up of malignancies in haemophilia. Furthermore, it remains unclear whether or not morbidity and mortality outcomes associated with malignancies are affected by haemophilia or by its treatment. Through presentation of five malignancies - prostate cancer, colorectal cancer, acute leukaemia, bladder cancer and hepatocellular carcinoma - important issues are highlighted, such as risk from bleeding as a symptom of malignancy; risks from invasive screenings and how these should be handled in haemophilic individuals; the implications of chemotherapy and treatment schedules, bone marrow suppression, radiotherapy, or surgery; and the likelihood of an interaction between treatment for haemophilia and malignancy outcomes. Ultimately, the aim is to establish consensus guidelines to direct and harmonize future treatment policy for malignant disease in the haemophilic population.

Seminars in Hematology, 2006

Patients with mild/moderate hemophilia A (MHA) may develop inhibitors to factor VIII (FVIII). In ... more Patients with mild/moderate hemophilia A (MHA) may develop inhibitors to factor VIII (FVIII). In this condition, FVIII clotting activity (FVIII:C) baseline levels may remain stable for some patients, but may be reduced to less than 0.01 U/mL for others. Several risk factors for the development of inhibitors in MHA have been proposed. Genetic factors, such as mutations in the FVIII gene, may play a central role; however, other influences, such as intensive treatment with FVIII products, may also be important. Optimal treatment regimens have yet to be determined, not only for the eradication of inhibitors, but also for the management or surgical prophylaxis of hemorrhages associated with this condition. Several treatment options for the control of bleeding in patients with MHA and inhibitors (MHAI) are currently available, and the choice of therapeutic strategy should be given careful consideration; some treatments may produce an anamnestic response, thus delaying the return to FVIII:C baseline levels and adversely affecting the duration of the severe bleeding phenotype. To increase our knowledge of MHAI, a retrospective collection of data is currently being performed among hemophilia centers in France and Belgium. Based on five examples of patients with MHAI collated from preliminary study data, we illustrate the impact on inhibitor outcome of the therapeutic choices used to treat bleeding episodes in these patients.

Haemophilia, 2008

Summary. In mild/moderate haemophilia A (MHA) patients, many factor VIII (FVIII) gene defects, m... more Summary. In mild/moderate haemophilia A (MHA) patients, many factor VIII (FVIII) gene defects, mainly missense mutations, have been identified and greatly improved the understanding of the structure and function of FVIII molecule. Characterization of the molecular mechanisms involved in MHA has helped to identify regions critical for proper FVIII biosynthesis, thrombin activation, intramolecular stability as well as binding regions for important intermolecular interactions with von Willebrand factor, factor IXa and the phospholipid surface. Some missense mutations were also recognized as contributing factors to inhibitor development in MHA, in parallel to acquired factors such as inflammatory state or intensity of treatment. Treatment of MHA with inhibitor patients raises questions on how best to stop or prevent bleeding episodes and eradicate the inhibitor. Longitudinal data collection is currently being conducted in France and Belgium to enhance our knowledge in this field and to further help make treatment decision. The description of mutations in MHA finally contributed to the identification of epitopes involved in the immune response to FVIII. In some patients, the epitope specificity of inhibitor antibodies recognizing normal exogenous FVIII alone and not patient (‘self’) FVIII was described. This distinguished epitope specificity could also be demonstrated at the T-cell clonal level. One might expect that these molecular studies will have a major impact on development of new FVIII products in the future.

Haemophilia : the official journal of the World Federation of Hemophilia, 2013

Immune tolerance induction (ITI) can eliminate factor VIII (FVIII) inhibitory antibodies that app... more Immune tolerance induction (ITI) can eliminate factor VIII (FVIII) inhibitory antibodies that appear during FVIII replacement therapy. If first-line ITI fails, switching to a different FVIII concentrate, especially one containing von Willebrand factor (VWF), has been advocated. The objective of the study was to assess the efficacy and safety of Haemate(®) P, a plasma-derived FVIII concentrate containing high levels of VWF, as ITI in severe haemophilia A patients who had failed at least one prior ITI attempt with a different FVIII concentrate. In this multicentre, observational study, Haemate(®) P was administered at a starting dose of 83-308 IU kg(-1) day(-1) (1500-6000 IU day(-1)). Efficacy was assessed by standard criteria (e.g. Bethesda titre, FVIII recovery and half-life), and bleeding characteristics. Nine patients from six haemophilia centres were treated with Haemate(®) P after failing one (n = 2), two (n = 5) or three (n = 2) prior ITI courses. The median time from inhibitor detection to Haemate(®) P treatment was 5.4 years. The median Haemate(®) P dose was 134 IU kg(-1), and the median treatment duration 32 months. During median of 47 months of follow-up, complete response, partial response and treatment failure were observed in one, three and five patients respectively. Five patients experienced seven adverse events (AEs), including two serious AEs (sepsis). Haemate(®) P was discontinued due to an AE in one patient with a partial response. Haemate(®) P salvage ITI resulted in complete or partial tolerization in four of nine patients (44%) who had failed previous ITI attempts using different FVIII concentrates.

Haemophilia : the official journal of the World Federation of Hemophilia, 2011

Assessing response to treatment with bypassing agents presents a substantial challenge in the tre... more Assessing response to treatment with bypassing agents presents a substantial challenge in the treatment of patients with haemophilia and inhibitors. Rapid and accurate identification of bleeding episodes that are non-responsive to bypassing therapy with either Factor Eight Inhibitor Bypassing Activity (FEIBA; Baxter AG) or recombinant activated factor VII (rFVIIa; NovoSeven® , Novo Nordisk A/S) is essential to guide treatment decisions and optimize patient outcomes through early intervention. Although both bypassing agents are effective, differential responses to therapy necessitate multiple therapeutic options. This article provides a consensus definition for non-life-threatening joint and muscle bleeds that are non-responsive to bypassing agents. An international panel of seven physicians met in December 2008 to develop the consensus definition using a modified National Institutes of Health Consensus Development Conference method. The consequent definition of non-life-threatening bleeding episodes that are non-responsive to bypassing treatment provides a global picture of the condition of the patient during such an event. Identification of non-responsiveness is based on various criteria: pain, swelling/tension, mobility, patient perception and laboratory parameters. Criteria can be assessed subjectively by the patient/parent and/or objectively by the clinician. Although the precise timing of each determination should be at the discretion of the physician, bleeds should be considered non-responsive if the clinical situation meets the specified criteria 24 h from the start of treatment. Although it is not intended to replace clinical judgment, this definition can guide the optimal course of treatment for patients with haemophilia and inhibitors.

Journal of thrombosis and haemostasis : JTH, 2011

The development of an inhibitor is the major complication facing patients with hemophilia A trea... more The development of an inhibitor is the major complication facing patients with hemophilia A treated by administration of factor (F) VIII concentrates. Restoration of tolerance to FVIII can be achieved by prolonged administration of FVIII (immune tolerance induction, ITI). Although ITI has been used for more than 30years in patients with hemophilia A and inhibitor, its mechanism of action is still poorly understood. As administration of high doses of antigen can induce the apoptosis of the T cells recognizing the antigen, a potential mechanism of action of ITI may be the deletion of FVIII-specific T cells. We studied the CD4+ T-cell response to FVIII in five (one mild, one moderate and three severe) patients successfully desensitized by administration of FVIII and in control subjects. Following repeated stimulation with autologous dendritic cells loaded with FVIII, FVIII-specific T oligoclonal cell lines were expanded from the blood of one of the successfully desensitized patients. The FVIII-specific T cells produced IL-5, IL-13 and IL-2. By contrast, FVIII-specific T-cell lines could not be derived from three patients with mild hemophilia A without inhibitor or from four normal control subjects. These data represent the first analysis of the cellular mechanisms regulating the induction of tolerance to FVIII. They demonstrate that successful tolerance induction may occur without deletion of FVIII-specific T cells.

Haemophilia : the official journal of the World Federation of Hemophilia, 2012

Journal of Thrombosis and Haemostasis, 2004

Summary. Background: Antibodies to glycoprotein (GP) IIb-IIIa and/or HLA may render platelet tran... more Summary. Background: Antibodies to glycoprotein (GP) IIb-IIIa and/or HLA may render platelet transfusions ineffective to stop bleeding or to cover surgery in patients with Glanzmann's thrombasthenia (GT). Anecdotal reports suggest recombinant factor (rF)VIIa might be a therapeutic alternative in these situations. Objectives: An international survey was conducted to evaluate further the efficacy and safety of rFVIIa in GT patients. Patients: We analyzed the use of rFVIIa during 34 surgical/invasive procedures and 108 bleeding episodes in 59 GT patients including 29 with current or previous antiplatelet antibodies, and 23 with a history of refractoriness to platelet transfusion. Results: rFVIIa was effective in 29 of the 31 evaluable procedures, and in 77 of the 103 evaluable bleeding episodes of which eight had a recurrence. A significantly higher success rate was observed in severe bleeding episodes when an arbitrarily defined ‘optimal regimen’ derived from the Canadian pilot study results (≥ 80 µg kg−1 rFVIIa/injection, dosing interval ≤ 2.5 h, three or more doses before failure declaration) was used compared with other regimens (77%; 24/31 vs. 48%, 19/40; χ2, P = 0.010). Patients given maintenance doses had significantly fewer recurrences within 48 h of bleed cessation compared with those not given any (Fisher's exact test, P = 0.022). One thromboembolic event and one blood clot in the ureter occurring in surgical patients following prolonged continuous infusion of high-dose rFVIIa and antifibrinolytic drug use have been previously reported. Conclusion: rFVIIa seems a potential alternative to platelet transfusion in GT patients, particularly in those with antiplatelet antibodies and/or platelet refractoriness.

Thromb …, 2000

The treatment of bleeds in Glanzmann's thrombasthenia is a challenging issue, especially ... more The treatment of bleeds in Glanzmann's thrombasthenia is a challenging issue, especially when repeated platelet transfusions have induced anti-glycoprotein (GP) IIb-IIIa or anti-HLA allo-immunisation. In an attempt to find an alternative treatment regimen, we used recombinant factor VIIa (rFVIIa, NovoSeven, Novo Nordisk, Denmark) as first-line therapy in 3 patients with Glanzmann's thrombasthenia and anti-GPIIb-IIIa iso-antibodies who were scheduled for invasive procedures. The administration of an initial bolus dose of rFVIIa (70-110 microg/kg) was immediately followed by continuous infusion at the rate of 9-30 microg/kg/h for 3-15 days. The treatment resulted in an excellent clinical efficacy and tolerance in 2 cases. In the third patient, whereas efficacy was excellent at the surgical site, pharyngonasal bleeds of traumatic origin persisted for 10 days, and a severe thromboembolic complication occurred 5 days after discontinuation of rFVIIa. Complementary studies are needed for patients with congenital platelet disorders in order to evaluate the safety and the potential therapeutic place of rFVIIa treatment.

Blood coagulation & fibrinolysis, 2000

Recombinant activated factor VII (rFVIIa; NovoSeven, Novo Nordisk A/S, Bagsvaerd, Denmark), used ... more Recombinant activated factor VII (rFVIIa; NovoSeven, Novo Nordisk A/S, Bagsvaerd, Denmark), used extensively for the management of hemophilia patients with inhibitors, has also been shown to be effective in the treatment of severe bleeding episodes and for coverage of surgical procedures in patients with platelet disorders. Cases include seven patients with congenital platelet disorders [Glanzmann thrombasthenia (n = 5), Bernard-Soulier syndrome (n = 1), platelet type (pseudo-) von Willebrand disease (n = 1)] and two patients with acquired thrombocytopathy associated with myelodysplastic syndrome and uremia. The clinical efficacy of rFVIIa in functional platelet disorders has been reported as good or excellent, although some cases of ineffectiveness exist. The agent is well tolerated with a single published case of thromboembolism as a postoperative complication. In addition to these reported cases, there are others that remain unreported and unpublished. An International Registry on Recombinant Factor VIIa and Congenital Platelet Disorders (forms in Appendix 1) has been established to obtain more safety and efficacy data on patients with congenital platelet disorders treated with NovoSeven. Analysis of data from this larger population will allow better comprehension of the role of NovoSeven in these disorders, and assist in the design of formal studies to address issues associated with the treatment of these disorders.

Blood coagulation & …, 1998

A questionnaire was sent to 28 haemophilia treatment centres known to have used recombinant activ... more A questionnaire was sent to 28 haemophilia treatment centres known to have used recombinant activated factor VII (rFVIIa; NovoSeven, Novo Nordisk, Bagsvaerd, Denmark), to collect data on continuous infusion of this product. This mode of administration was recently introduced for rFVIIa but there are several questions which remain to be answered in order to optimize this technique. Of the 26 responding centres, 14 had used rFVIIa in continuous infusion for 40 treatment episodes over a total of 283 days. In most of the cases the treatment was targeted at a factor VII level of 10 IU/ml, monitored by the one-stage clotting assay. This seemed to be adequate for most of the haemorrhagic and surgical procedures. Pretreatment pharmacokinetic evaluation was performed in only a minority of the cases but is probably of great importance given the wide variation observed in the clearance values. A strategy was necessary to prevent local thrombophlebitis, at least for infusions in peripheral veins; parallel infusion of heparin, saline or dextrose-saline proved effective. The question of optimal monitoring needs further attention. Haemorrhagic complications were significantly less frequent when treatment was combined with the antifibrinolytic tranexamic acid.

Human genetics, 2001

Congenital afibrinogenemia is an autosomal recessive disorder characterized by the complete absen... more Congenital afibrinogenemia is an autosomal recessive disorder characterized by the complete absence of detectable fibrinogen. We previously identified the first causative mutations for this disease in a non-consanguineous Swiss family. These were homozygous deletions of approximately 11 kb of the fibrinogen alpha chain gene (FGA). Our subsequent study revealed that the majority of cases were attributable to truncating mutations in FGA, with the most common mutation affecting the donor splice site in FGA intron 4 (IVS4+1 G→T). Here, we report 13 further unrelated patients with mutations in FGA, confirming the relative importance of this gene compared with FGG and FGB in the molecular aetiology of afibrinogenemia. Three other patients were homozygous for mutations in FGG. Eight novel mutations were identified: five in FGA and three in FGG. Sufficient mutation data is now available to permit an effective strategy for the genetic diagnosis of congenital afibrinogenemia.

Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis, 2003

Factor VII (FVII) is a plasma glycoprotein that plays a key role in the initiation of blood coagu... more Factor VII (FVII) is a plasma glycoprotein that plays a key role in the initiation of blood coagulation cascade. Inherited FVII deficiency is a rare autosomal recessive disorder with a wide heterogeneous clinical pattern. The severe form may be associated with intracranial haemorrhages occurring closely to birth with a high mortality rate. In the present article, we report two novel cases of neonatal intracerebral bleeding associated with FVII activity levels below 1% of normal. FVII genotyping investigations revealed particular genotypes including the deleterious Cys135Arg mutation and a novel Ser52Stop nonsense mutation at the homozygous state. Both mutations, through different mechanisms, are expected to be inconsistent with the production of functional FVII. These putative mechanisms are discussed through a review of the literature on phenotypic and genotypic characteristics of cerebral haemorrhages in severe inherited FVII deficiency.

Haematologica, 2004

Biological phenotypes in FVII deficiency © F e r r a t a S t o r t i F o u n d a t i o n haematol... more Biological phenotypes in FVII deficiency © F e r r a t a S t o r t i F o u n d a t i o n haematologica 2004; 89(6):June 2004 M. Giansily-Blazot et al. 708 © F e r r a t a S t o r t i F o u n d a t i o n © F e r r a t a S t o r t i F o u n d a t i o n

Journal of thrombosis and haemostasis : JTH, 2004

Haematologica, 2005

... References 1. Attal M, Harousseau J, Stoppa A. A prospective, randomized trial of autologous ... more ... References 1. Attal M, Harousseau J, Stoppa A. A prospective, randomized trial of autologous bone marrow transplantation and chemo-therapy in multiple myeloma. ... III 4 F/29 22 25 Delivery¥1 0/0 0 Sri Lanka g 23022 t W497C het 13 Appendicectomy 0/0 ...

Journal of Thrombosis and Haemostasis, 2003

Summary. Mutations responsible for mild/moderate hemophilia A were extensively characterized ove... more Summary. Mutations responsible for mild/moderate hemophilia A were extensively characterized over the last 15 years and more than 200 mutations have been identified. However, most of the molecular mechanisms responsible for the reduced factor (F)VIII levels in patients' plasma were determined only recently. Recent progresses in the study of the FVIII molecule three-dimensional structure provided a major insight for understanding molecular events leading to mild/moderate hemophilia A. This allowed prediction of mutations impairing FVIII folding and intracellular processing, which result in reduced FVIII secretion. Mutations potentially slowing down FVIII activation by thrombin were also identified. A number of mutations were also predicted to result in altered stability of activated FVIII. Biochemical analyses allowed identification of mutations reducing FVIII production. Mutations impairing FVIII stability in plasma, by reducing FVIII binding to von Willebrand factor (VWF) were also characterized. Defects in FVIII activity, notably slow activation by thrombin, or abnormal interaction with FIXa, were also recently demonstrated. Biochemical analysis of FVIII variants provided information regarding the structure/function relationship of the FVIII molecule and validated predictions of the three-dimensional structure of the molecule. These observations also contributed to explain the discrepant activities recorded for some FVIII variants using different types of FVIII assays. Altogether, the study of the biochemical properties of FVIII variants and the evaluation of the effects of mutations in three-dimensional models of FVIII identified molecular mechanisms potentially explaining reduced FVIII levels for a majority of patients with mild/moderate hemophilia A. It is expected that these studies will improve diagnosis and treatment of this disease.

Haemophilia, 2007

Summary. The presence of inhibitory antibodies to clotting factors complicates the treatment of ... more Summary. The presence of inhibitory antibodies to clotting factors complicates the treatment of bleeding in haemophilia patients. For patients with high-titre inhibitors, bypassing agents are essential to haemostatic management. To determine optimal treatment practices, an international panel of physicians convened to develop a systematic treatment approach for problem bleeds (i.e. bleeds that are unresponsive to initial therapy with a single agent within a reasonable amount of time) in haemophilia patients with inhibitors. Aim: The goal of this panel was to develop a consensus algorithm that would aid physicians in considering a variety of treatment approaches to optimize patient care by preventing extensive therapy with inadequate treatments that may lead to suboptimal patient outcomes and unnecessary costs. Methods: Consensus opinions were analyzed for clinical preferences at different time periods, depending on patient response to treatment. Decision-making points were defined based on the type of bleed: every 8–12 h for the first 24 h, then every 24 h thereafter for limb-threatening bleeds; every 2–4 h for 2–7 days for life-threatening bleeds. Results: The resultant consensus guidelines provide a generalized methodology to guide the treatment of problem bleeds in patients with severe haemophilia A and inhibitors, and emphasize changing treatment at the first sign of an inadequate haemostatic response. The treatment algorithms apply to both paediatric and adult patients, although the differences between the two groups were reviewed. Conclusion: These guidelines are focused on optimising the timing of treatment decisions, which may lead to faster responses and improved outcomes.

Haematologica-the Hematology Journal, 2008

Haemophilia : the official journal of the World Federation of Hemophilia, 2012

The Malignancy in Haemophilia Workshop Group convened a consensus working group of haematologists... more The Malignancy in Haemophilia Workshop Group convened a consensus working group of haematologists and oncologists to review topics related to malignancy in haemophilia. The treatment of malignant disease in this population is increasingly relevant as both outcome and lifespan continue to improve. Although adequate guidance exists for control of spontaneous bleeding episodes and of haemostasis in general surgery, information for management of haemostasis in patients with various malignancies is sparse. To date, no clinical guidelines exist for management of complex bleeding problems, diagnosis, therapy and follow-up of malignancies in haemophilia. Furthermore, it remains unclear whether or not morbidity and mortality outcomes associated with malignancies are affected by haemophilia or by its treatment. Through presentation of five malignancies - prostate cancer, colorectal cancer, acute leukaemia, bladder cancer and hepatocellular carcinoma - important issues are highlighted, such as risk from bleeding as a symptom of malignancy; risks from invasive screenings and how these should be handled in haemophilic individuals; the implications of chemotherapy and treatment schedules, bone marrow suppression, radiotherapy, or surgery; and the likelihood of an interaction between treatment for haemophilia and malignancy outcomes. Ultimately, the aim is to establish consensus guidelines to direct and harmonize future treatment policy for malignant disease in the haemophilic population.

Seminars in Hematology, 2006

Patients with mild/moderate hemophilia A (MHA) may develop inhibitors to factor VIII (FVIII). In ... more Patients with mild/moderate hemophilia A (MHA) may develop inhibitors to factor VIII (FVIII). In this condition, FVIII clotting activity (FVIII:C) baseline levels may remain stable for some patients, but may be reduced to less than 0.01 U/mL for others. Several risk factors for the development of inhibitors in MHA have been proposed. Genetic factors, such as mutations in the FVIII gene, may play a central role; however, other influences, such as intensive treatment with FVIII products, may also be important. Optimal treatment regimens have yet to be determined, not only for the eradication of inhibitors, but also for the management or surgical prophylaxis of hemorrhages associated with this condition. Several treatment options for the control of bleeding in patients with MHA and inhibitors (MHAI) are currently available, and the choice of therapeutic strategy should be given careful consideration; some treatments may produce an anamnestic response, thus delaying the return to FVIII:C baseline levels and adversely affecting the duration of the severe bleeding phenotype. To increase our knowledge of MHAI, a retrospective collection of data is currently being performed among hemophilia centers in France and Belgium. Based on five examples of patients with MHAI collated from preliminary study data, we illustrate the impact on inhibitor outcome of the therapeutic choices used to treat bleeding episodes in these patients.

Haemophilia, 2008

Summary. In mild/moderate haemophilia A (MHA) patients, many factor VIII (FVIII) gene defects, m... more Summary. In mild/moderate haemophilia A (MHA) patients, many factor VIII (FVIII) gene defects, mainly missense mutations, have been identified and greatly improved the understanding of the structure and function of FVIII molecule. Characterization of the molecular mechanisms involved in MHA has helped to identify regions critical for proper FVIII biosynthesis, thrombin activation, intramolecular stability as well as binding regions for important intermolecular interactions with von Willebrand factor, factor IXa and the phospholipid surface. Some missense mutations were also recognized as contributing factors to inhibitor development in MHA, in parallel to acquired factors such as inflammatory state or intensity of treatment. Treatment of MHA with inhibitor patients raises questions on how best to stop or prevent bleeding episodes and eradicate the inhibitor. Longitudinal data collection is currently being conducted in France and Belgium to enhance our knowledge in this field and to further help make treatment decision. The description of mutations in MHA finally contributed to the identification of epitopes involved in the immune response to FVIII. In some patients, the epitope specificity of inhibitor antibodies recognizing normal exogenous FVIII alone and not patient (‘self’) FVIII was described. This distinguished epitope specificity could also be demonstrated at the T-cell clonal level. One might expect that these molecular studies will have a major impact on development of new FVIII products in the future.

Haemophilia : the official journal of the World Federation of Hemophilia, 2013

Immune tolerance induction (ITI) can eliminate factor VIII (FVIII) inhibitory antibodies that app... more Immune tolerance induction (ITI) can eliminate factor VIII (FVIII) inhibitory antibodies that appear during FVIII replacement therapy. If first-line ITI fails, switching to a different FVIII concentrate, especially one containing von Willebrand factor (VWF), has been advocated. The objective of the study was to assess the efficacy and safety of Haemate(®) P, a plasma-derived FVIII concentrate containing high levels of VWF, as ITI in severe haemophilia A patients who had failed at least one prior ITI attempt with a different FVIII concentrate. In this multicentre, observational study, Haemate(®) P was administered at a starting dose of 83-308 IU kg(-1) day(-1) (1500-6000 IU day(-1)). Efficacy was assessed by standard criteria (e.g. Bethesda titre, FVIII recovery and half-life), and bleeding characteristics. Nine patients from six haemophilia centres were treated with Haemate(®) P after failing one (n = 2), two (n = 5) or three (n = 2) prior ITI courses. The median time from inhibitor detection to Haemate(®) P treatment was 5.4 years. The median Haemate(®) P dose was 134 IU kg(-1), and the median treatment duration 32 months. During median of 47 months of follow-up, complete response, partial response and treatment failure were observed in one, three and five patients respectively. Five patients experienced seven adverse events (AEs), including two serious AEs (sepsis). Haemate(®) P was discontinued due to an AE in one patient with a partial response. Haemate(®) P salvage ITI resulted in complete or partial tolerization in four of nine patients (44%) who had failed previous ITI attempts using different FVIII concentrates.

Haemophilia : the official journal of the World Federation of Hemophilia, 2011

Assessing response to treatment with bypassing agents presents a substantial challenge in the tre... more Assessing response to treatment with bypassing agents presents a substantial challenge in the treatment of patients with haemophilia and inhibitors. Rapid and accurate identification of bleeding episodes that are non-responsive to bypassing therapy with either Factor Eight Inhibitor Bypassing Activity (FEIBA; Baxter AG) or recombinant activated factor VII (rFVIIa; NovoSeven® , Novo Nordisk A/S) is essential to guide treatment decisions and optimize patient outcomes through early intervention. Although both bypassing agents are effective, differential responses to therapy necessitate multiple therapeutic options. This article provides a consensus definition for non-life-threatening joint and muscle bleeds that are non-responsive to bypassing agents. An international panel of seven physicians met in December 2008 to develop the consensus definition using a modified National Institutes of Health Consensus Development Conference method. The consequent definition of non-life-threatening bleeding episodes that are non-responsive to bypassing treatment provides a global picture of the condition of the patient during such an event. Identification of non-responsiveness is based on various criteria: pain, swelling/tension, mobility, patient perception and laboratory parameters. Criteria can be assessed subjectively by the patient/parent and/or objectively by the clinician. Although the precise timing of each determination should be at the discretion of the physician, bleeds should be considered non-responsive if the clinical situation meets the specified criteria 24 h from the start of treatment. Although it is not intended to replace clinical judgment, this definition can guide the optimal course of treatment for patients with haemophilia and inhibitors.

Journal of thrombosis and haemostasis : JTH, 2011

The development of an inhibitor is the major complication facing patients with hemophilia A trea... more The development of an inhibitor is the major complication facing patients with hemophilia A treated by administration of factor (F) VIII concentrates. Restoration of tolerance to FVIII can be achieved by prolonged administration of FVIII (immune tolerance induction, ITI). Although ITI has been used for more than 30years in patients with hemophilia A and inhibitor, its mechanism of action is still poorly understood. As administration of high doses of antigen can induce the apoptosis of the T cells recognizing the antigen, a potential mechanism of action of ITI may be the deletion of FVIII-specific T cells. We studied the CD4+ T-cell response to FVIII in five (one mild, one moderate and three severe) patients successfully desensitized by administration of FVIII and in control subjects. Following repeated stimulation with autologous dendritic cells loaded with FVIII, FVIII-specific T oligoclonal cell lines were expanded from the blood of one of the successfully desensitized patients. The FVIII-specific T cells produced IL-5, IL-13 and IL-2. By contrast, FVIII-specific T-cell lines could not be derived from three patients with mild hemophilia A without inhibitor or from four normal control subjects. These data represent the first analysis of the cellular mechanisms regulating the induction of tolerance to FVIII. They demonstrate that successful tolerance induction may occur without deletion of FVIII-specific T cells.

Haemophilia : the official journal of the World Federation of Hemophilia, 2012

Journal of Thrombosis and Haemostasis, 2004

Summary. Background: Antibodies to glycoprotein (GP) IIb-IIIa and/or HLA may render platelet tran... more Summary. Background: Antibodies to glycoprotein (GP) IIb-IIIa and/or HLA may render platelet transfusions ineffective to stop bleeding or to cover surgery in patients with Glanzmann's thrombasthenia (GT). Anecdotal reports suggest recombinant factor (rF)VIIa might be a therapeutic alternative in these situations. Objectives: An international survey was conducted to evaluate further the efficacy and safety of rFVIIa in GT patients. Patients: We analyzed the use of rFVIIa during 34 surgical/invasive procedures and 108 bleeding episodes in 59 GT patients including 29 with current or previous antiplatelet antibodies, and 23 with a history of refractoriness to platelet transfusion. Results: rFVIIa was effective in 29 of the 31 evaluable procedures, and in 77 of the 103 evaluable bleeding episodes of which eight had a recurrence. A significantly higher success rate was observed in severe bleeding episodes when an arbitrarily defined ‘optimal regimen’ derived from the Canadian pilot study results (≥ 80 µg kg−1 rFVIIa/injection, dosing interval ≤ 2.5 h, three or more doses before failure declaration) was used compared with other regimens (77%; 24/31 vs. 48%, 19/40; χ2, P = 0.010). Patients given maintenance doses had significantly fewer recurrences within 48 h of bleed cessation compared with those not given any (Fisher's exact test, P = 0.022). One thromboembolic event and one blood clot in the ureter occurring in surgical patients following prolonged continuous infusion of high-dose rFVIIa and antifibrinolytic drug use have been previously reported. Conclusion: rFVIIa seems a potential alternative to platelet transfusion in GT patients, particularly in those with antiplatelet antibodies and/or platelet refractoriness.

Thromb …, 2000

The treatment of bleeds in Glanzmann's thrombasthenia is a challenging issue, especially ... more The treatment of bleeds in Glanzmann's thrombasthenia is a challenging issue, especially when repeated platelet transfusions have induced anti-glycoprotein (GP) IIb-IIIa or anti-HLA allo-immunisation. In an attempt to find an alternative treatment regimen, we used recombinant factor VIIa (rFVIIa, NovoSeven, Novo Nordisk, Denmark) as first-line therapy in 3 patients with Glanzmann's thrombasthenia and anti-GPIIb-IIIa iso-antibodies who were scheduled for invasive procedures. The administration of an initial bolus dose of rFVIIa (70-110 microg/kg) was immediately followed by continuous infusion at the rate of 9-30 microg/kg/h for 3-15 days. The treatment resulted in an excellent clinical efficacy and tolerance in 2 cases. In the third patient, whereas efficacy was excellent at the surgical site, pharyngonasal bleeds of traumatic origin persisted for 10 days, and a severe thromboembolic complication occurred 5 days after discontinuation of rFVIIa. Complementary studies are needed for patients with congenital platelet disorders in order to evaluate the safety and the potential therapeutic place of rFVIIa treatment.

Blood coagulation & fibrinolysis, 2000

Recombinant activated factor VII (rFVIIa; NovoSeven, Novo Nordisk A/S, Bagsvaerd, Denmark), used ... more Recombinant activated factor VII (rFVIIa; NovoSeven, Novo Nordisk A/S, Bagsvaerd, Denmark), used extensively for the management of hemophilia patients with inhibitors, has also been shown to be effective in the treatment of severe bleeding episodes and for coverage of surgical procedures in patients with platelet disorders. Cases include seven patients with congenital platelet disorders [Glanzmann thrombasthenia (n = 5), Bernard-Soulier syndrome (n = 1), platelet type (pseudo-) von Willebrand disease (n = 1)] and two patients with acquired thrombocytopathy associated with myelodysplastic syndrome and uremia. The clinical efficacy of rFVIIa in functional platelet disorders has been reported as good or excellent, although some cases of ineffectiveness exist. The agent is well tolerated with a single published case of thromboembolism as a postoperative complication. In addition to these reported cases, there are others that remain unreported and unpublished. An International Registry on Recombinant Factor VIIa and Congenital Platelet Disorders (forms in Appendix 1) has been established to obtain more safety and efficacy data on patients with congenital platelet disorders treated with NovoSeven. Analysis of data from this larger population will allow better comprehension of the role of NovoSeven in these disorders, and assist in the design of formal studies to address issues associated with the treatment of these disorders.

Blood coagulation & …, 1998

A questionnaire was sent to 28 haemophilia treatment centres known to have used recombinant activ... more A questionnaire was sent to 28 haemophilia treatment centres known to have used recombinant activated factor VII (rFVIIa; NovoSeven, Novo Nordisk, Bagsvaerd, Denmark), to collect data on continuous infusion of this product. This mode of administration was recently introduced for rFVIIa but there are several questions which remain to be answered in order to optimize this technique. Of the 26 responding centres, 14 had used rFVIIa in continuous infusion for 40 treatment episodes over a total of 283 days. In most of the cases the treatment was targeted at a factor VII level of 10 IU/ml, monitored by the one-stage clotting assay. This seemed to be adequate for most of the haemorrhagic and surgical procedures. Pretreatment pharmacokinetic evaluation was performed in only a minority of the cases but is probably of great importance given the wide variation observed in the clearance values. A strategy was necessary to prevent local thrombophlebitis, at least for infusions in peripheral veins; parallel infusion of heparin, saline or dextrose-saline proved effective. The question of optimal monitoring needs further attention. Haemorrhagic complications were significantly less frequent when treatment was combined with the antifibrinolytic tranexamic acid.

Human genetics, 2001

Congenital afibrinogenemia is an autosomal recessive disorder characterized by the complete absen... more Congenital afibrinogenemia is an autosomal recessive disorder characterized by the complete absence of detectable fibrinogen. We previously identified the first causative mutations for this disease in a non-consanguineous Swiss family. These were homozygous deletions of approximately 11 kb of the fibrinogen alpha chain gene (FGA). Our subsequent study revealed that the majority of cases were attributable to truncating mutations in FGA, with the most common mutation affecting the donor splice site in FGA intron 4 (IVS4+1 G→T). Here, we report 13 further unrelated patients with mutations in FGA, confirming the relative importance of this gene compared with FGG and FGB in the molecular aetiology of afibrinogenemia. Three other patients were homozygous for mutations in FGG. Eight novel mutations were identified: five in FGA and three in FGG. Sufficient mutation data is now available to permit an effective strategy for the genetic diagnosis of congenital afibrinogenemia.

Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis, 2003

Factor VII (FVII) is a plasma glycoprotein that plays a key role in the initiation of blood coagu... more Factor VII (FVII) is a plasma glycoprotein that plays a key role in the initiation of blood coagulation cascade. Inherited FVII deficiency is a rare autosomal recessive disorder with a wide heterogeneous clinical pattern. The severe form may be associated with intracranial haemorrhages occurring closely to birth with a high mortality rate. In the present article, we report two novel cases of neonatal intracerebral bleeding associated with FVII activity levels below 1% of normal. FVII genotyping investigations revealed particular genotypes including the deleterious Cys135Arg mutation and a novel Ser52Stop nonsense mutation at the homozygous state. Both mutations, through different mechanisms, are expected to be inconsistent with the production of functional FVII. These putative mechanisms are discussed through a review of the literature on phenotypic and genotypic characteristics of cerebral haemorrhages in severe inherited FVII deficiency.

Haematologica, 2004

Biological phenotypes in FVII deficiency © F e r r a t a S t o r t i F o u n d a t i o n haematol... more Biological phenotypes in FVII deficiency © F e r r a t a S t o r t i F o u n d a t i o n haematologica 2004; 89(6):June 2004 M. Giansily-Blazot et al. 708 © F e r r a t a S t o r t i F o u n d a t i o n © F e r r a t a S t o r t i F o u n d a t i o n

Journal of thrombosis and haemostasis : JTH, 2004

Haematologica, 2005

... References 1. Attal M, Harousseau J, Stoppa A. A prospective, randomized trial of autologous ... more ... References 1. Attal M, Harousseau J, Stoppa A. A prospective, randomized trial of autologous bone marrow transplantation and chemo-therapy in multiple myeloma. ... III 4 F/29 22 25 Delivery¥1 0/0 0 Sri Lanka g 23022 t W497C het 13 Appendicectomy 0/0 ...

Journal of Thrombosis and Haemostasis, 2003

Summary. Mutations responsible for mild/moderate hemophilia A were extensively characterized ove... more Summary. Mutations responsible for mild/moderate hemophilia A were extensively characterized over the last 15 years and more than 200 mutations have been identified. However, most of the molecular mechanisms responsible for the reduced factor (F)VIII levels in patients' plasma were determined only recently. Recent progresses in the study of the FVIII molecule three-dimensional structure provided a major insight for understanding molecular events leading to mild/moderate hemophilia A. This allowed prediction of mutations impairing FVIII folding and intracellular processing, which result in reduced FVIII secretion. Mutations potentially slowing down FVIII activation by thrombin were also identified. A number of mutations were also predicted to result in altered stability of activated FVIII. Biochemical analyses allowed identification of mutations reducing FVIII production. Mutations impairing FVIII stability in plasma, by reducing FVIII binding to von Willebrand factor (VWF) were also characterized. Defects in FVIII activity, notably slow activation by thrombin, or abnormal interaction with FIXa, were also recently demonstrated. Biochemical analysis of FVIII variants provided information regarding the structure/function relationship of the FVIII molecule and validated predictions of the three-dimensional structure of the molecule. These observations also contributed to explain the discrepant activities recorded for some FVIII variants using different types of FVIII assays. Altogether, the study of the biochemical properties of FVIII variants and the evaluation of the effects of mutations in three-dimensional models of FVIII identified molecular mechanisms potentially explaining reduced FVIII levels for a majority of patients with mild/moderate hemophilia A. It is expected that these studies will improve diagnosis and treatment of this disease.

Haemophilia, 2007

Summary. The presence of inhibitory antibodies to clotting factors complicates the treatment of ... more Summary. The presence of inhibitory antibodies to clotting factors complicates the treatment of bleeding in haemophilia patients. For patients with high-titre inhibitors, bypassing agents are essential to haemostatic management. To determine optimal treatment practices, an international panel of physicians convened to develop a systematic treatment approach for problem bleeds (i.e. bleeds that are unresponsive to initial therapy with a single agent within a reasonable amount of time) in haemophilia patients with inhibitors. Aim: The goal of this panel was to develop a consensus algorithm that would aid physicians in considering a variety of treatment approaches to optimize patient care by preventing extensive therapy with inadequate treatments that may lead to suboptimal patient outcomes and unnecessary costs. Methods: Consensus opinions were analyzed for clinical preferences at different time periods, depending on patient response to treatment. Decision-making points were defined based on the type of bleed: every 8–12 h for the first 24 h, then every 24 h thereafter for limb-threatening bleeds; every 2–4 h for 2–7 days for life-threatening bleeds. Results: The resultant consensus guidelines provide a generalized methodology to guide the treatment of problem bleeds in patients with severe haemophilia A and inhibitors, and emphasize changing treatment at the first sign of an inadequate haemostatic response. The treatment algorithms apply to both paediatric and adult patients, although the differences between the two groups were reviewed. Conclusion: These guidelines are focused on optimising the timing of treatment decisions, which may lead to faster responses and improved outcomes.

Haematologica-the Hematology Journal, 2008