A large-scale computational study of inhibitor risk in non-severe haemophilia A

Introduction: Extended Half-Life (EHL) concentrates were recently introduced to increase trough levels, decrease infusion frequency and potentially limiting the burden of treatment in patients with haemophilia (PWH) and their caregivers. Group-based studies have reported increased terminal half-life (THL) after switching from standard half-life (SHL) to EHL concentrates. However, available reports have included less than 30 patients and large-scale studies on switching from SHL to EHL concentrates are lacking. Aim: to assess individual changes in THL after switching from SHL to EHL concentrates in patients with severe haemophilia. Methods: Data were collected from the WAPPS (Web-Accessible Population Pharmacokinetics Service; www.wapps-hemo.org) database, which aims to assemble a database of pharmacokinetic data in PWH, develop and validate population pharmacokinetics models, and integrate these models within a Web-based calculator for individualized pharmacokinetic estimation. Informed consent was waived by the ethical committee. Data were selected from patients with both SHL and EHL infusions available. In case of multiple data, the last SHL and first EHL infusion were selected. THL was compared according to haemophilia type and age groups (children/adults). Comparisons were made based on haemophilia type and age by means of non-parametric paired testing. Results: Data were collected from 649 patients (1298 infusions) with severe haemophilia (89% haemophilia A; median age: 21.7 (11.5-37.7), weight: 66.0 kg (43.6-80.0) BMI: 22.5 (18.9-25.3); positive inhibitor history: 11.7%). All patients had received both SHL and EHL infusions. THL increased by a median factor 1.4 (1.2-1.7) in FVIII, leading to an absolute median increase of 4.1 hours (IQR: 2.0-6.7). However, THL was extended by less than 20% in 157 (27,2%) patients with haemophilia A after switching to EHL concentrates, leading to less than 48 minutes extension of THL. THL showed a decrease in 57 (9,9%) patients with haemophilia A after switching. For patients switching to EHL FIX, THL increased by a median factor 3.1 (2.4-3.6), leading to a median extension of 70.3 (52.5-90.8) hours in THL of FIX. All patients with haemophilia B showed an extension of THL after switching, with a minimum increase of 25%. Both the absolute and the relative increase in THL were similar for children and adults for both FVIII and FIX. Discussion: This was the first study to report large scale data on PWH switching from SHL to EHL concentrates. The results show that although an increased THL was observed at a group level, this was not the case for all individual patients. THL was extended by less than 20% after switching in 27% of patients with haemophilia A, with an actual decrease in THL in 9.9%. THL was extended by a minimum of 25% in patients with haemophilia B. This seems to support the use of individualized PK assessment in patients with haemophilia to guide clinical decisions on switching from SHL to EHL concentrates. Disclosures Versloot: Bayer: Research Funding. Germini:Bayer: Research Funding; NovoNordisk: Research Funding; Roche: Research Funding; Takeda: Research Funding. Iorio:Freeline: Research Funding; Pfizer: Research Funding; NovoNordisk: Research Funding; CSL: Research Funding; BioMarin: Research Funding; Octapharma: Research Funding; Takeda: Research Funding; Uniqure: Research Funding; Grifols: Research Funding; Roche: Research Funding; Bayer: Research Funding; Sanofi: Research Funding; Spark: Research Funding. Fischer:Bayer, Biogen, Pfizer, Baxter/Shire, and Novo Nordisk: Research Funding; Bayer, Baxter/Shire, SOBI/Biogen, CSL Behring, Octapharma, Pfizer, NovoNordisk: Research Funding; Bayer, Baxter, Biogen, CSL Behring, Freeline, Novo Nordisk, Pfizer, Roche, and Sobi: Consultancy.

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Intranasal DDAVP induced increases in plasma von Willebrand factor alter the pharmacokinetics of high-purity factor VIII concentrates in severe haemophilia A patients

Haemophilia ◽

10.1046/j.1365-2516.1999.00282.x ◽

1999 ◽

Vol 5 (2) ◽

pp. 88 ◽

Cited By ~ 2

Author(s):

STEVEN R. DEITCHER

Keyword(s):

Factor Viii ◽

Von Willebrand Factor ◽

High Purity ◽

Haemophilia A ◽

Severe Haemophilia ◽

Factor Viii Concentrates ◽

Von Willebrand ◽

Willebrand Factor

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Inhibitor treatment by rituximabin congenital haemophilia A

Hämostaseologie ◽

10.1055/s-0037-1617028 ◽

2009 ◽

Vol 29 (02) ◽

pp. 151-154 ◽

Cited By ~ 13

Author(s):

Escuriola Ettingshausen ◽

R. Linde ◽

G. Kropshofer ◽

L.-B. Zimmerhackl ◽

W. Kreuz ◽

...

Keyword(s):

B Cell ◽

Immune Tolerance ◽

High Titre ◽

Clotting Factor ◽

Severe Bleeding ◽

High Morbidity ◽

Haemophilia A ◽

Concomitant Treatment ◽

Bleeding Tendency ◽

Severe Haemophilia

SummaryThe development of neutralizing alloanti-bodies (inhibitors) to factor VIII (FVIII) is one of the most serious complications in the treatment of haemophiliacs. Inhibitors occur in approximately 20 to 30% of previously untreated patients (PUPs), predominantly children, with severe haemophilia A within the first 50 exposure days (ED). Immune tolerance induction (ITI) leads to complete elimination of the inhibitor in up to 80% of the patients and offers the possibility to restore regular FVIII prophylaxis. However, patients with high titre inhibitors, in whom standard ITI fails, usually impose with high morbidity and mortality and therefore prompting physicians to alternate therapy regimens. Rituximab, an anti-CD 20 monoclonal antibody has been successfully used in children and adults for the management of B-cell mediated disorders. We report on the use of a new protocol including rituximab in two adolescents with severe haemophilia A and high titre inhibitors, severe bleeding tendency and high clotting factor consumption after failing standard ITI. Both patients received a concomitant treatment with FVIII according to the Bonn protocol, cyclosporine A and immunoglobulin. Treatment with rituximab resulted in a temporary B-cell depletion leading to the disappearance of the inhibitor. FVIII recovery and half-life turned towards normal ranges. In patient 1 the inhibitor reappeared 14 months after the last rituximab administration. In patient 2 complete immune tolerance could be achieved for 60 months. Bleeding frequency diminished significantly and clinical joint status improved in both patients. In patient 1 the treatment course was complicated by aspergillosis and hepatitis B infection. Conclusion: Rituximab may be favourable for patients with congenital haemophilia, high-titre inhibitors and a severe clinical course in whom standard ITI has failed. Prospective studies are required to determine safety, efficacy and predictors of success.

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Inhibitorentwicklung nach früher hoher Exposition und Hirnblutung

Hämostaseologie ◽

10.1055/s-0037-1619091 ◽

2010 ◽

Vol 30 (S 01) ◽

pp. S115-S118

Author(s):

C. Moorthi ◽

A. Bade ◽

C. Niekrens ◽

G. Auerswald ◽

K. Haubold

Keyword(s):

High Titer ◽

Cerebral Haemorrhage ◽

High Dose ◽

Haemophilia A ◽

Severe Haemophilia ◽

Intron 22 Inversion ◽

Neurosurgical Intervention

SummarySevere haemophilia A was diagnosed postpartum in a newborn. The mother was known as a conductor (intron 22 inversion) and an uncle had a persistently high titer inhibitor after failed ITI.Due to a cephalhaematoma, a high-dose pdFVIII substitution was given within the first days after birth. At the age of six month a severe cerebral haemorrhage occurred, making a high-dose pdFVIII substitution and neurosurgical intervention necessary. Several days later a porth-a-cath-system was implanted. The development of a high titer inhibitor occured six days later, an ITI was started according to the Bonn Protocol. Initially rFVIIa was given in addition to the pdFVIII substitution. Seven days after the beginning of treatment the inhibitor was no longer detectable. At monthly intervals the FVIII dosage was reduced until the dosage complied with a prophylaxis in severe haemophilia A.The duration of the ITI was nine months. A total of 30 mg rFVIIa and 276 000 IU pdFVIII were used; costs in total: 280 173.60 Euro.

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Successful Electroconvulsive Treatment of a Schizophrenic Patient Suffering from Severe Haemophilia A

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650408 ◽

1996 ◽

Vol 75 (06) ◽

pp. 978-978 ◽

Cited By ~ 1

Author(s):

Theodora Glaub ◽

Bela Telek ◽

Zoltan Boda ◽

Sandor Szabo ◽

Geza Krall ◽

...

Keyword(s):

Schizophrenic Patient ◽

Haemophilia A ◽

Severe Haemophilia ◽

Electroconvulsive Treatment

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Management of Haemophilia in Sweden

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647991 ◽

1976 ◽

Vol 35 (03) ◽

pp. 510-521 ◽

Cited By ~ 13

Author(s):

Inga Marie Nilsson

Keyword(s):

Factor Viii ◽

Total Population ◽

Age Groups ◽

Factor Ix ◽

Haemophilia A ◽

Severe Haemophilia ◽

Haemophilia B ◽

Human Fraction ◽

Mild Haemophilia

SummaryThe incidence of living haemophiliacs in Sweden (total population 8.1 millions) is about 1:15,000 males and about 1:30,000 of the entire population. The number of haemophiliacs born in Sweden in 5-year periods between 1931-1975 (June) has remained almost unchanged. The total number of haemophilia families in Sweden is 284 (77% haemophilia A, 23% haemophilia B) with altogether 557 (436 with A and 121 with B) living haemophiliacs. Of the haemophilia A patients 40 % have severe, 18 % moderate, and 42 % mild, haemophilia. The distribution of the haemophilia B patients is about the same. Inhibitors have been demonstrated in 8% of the patients with severe haemophilia A and in 10% of those with severe haemophilia B.There are 2 main Haemophilia Centres (Stockholm, Malmo) to which haemophiliacs from the whole of Sweden are admitted for diagnosis, follow-up and treatment for severe bleedings, joint defects and surgery. Minor bleedings are treated at local hospitals in cooperation with the Haemophilia Centres. The concentrates available for treatment in haemophilia A are human fraction 1-0 (AHF-Kabi), cryoprecipitate, Antihaemophilic Factor (Hyland 4) and Kryobulin (Immuno, Wien). AHF-Kabi is the most commonly used preparation. The concentrates available for treatment in haemophilia B are Preconativ (Kabi) and Prothromplex (Immuno). Sufficient amounts of concentrates are available. In Sweden 3.2 million units of factor VIII and 1.0 million units of factor IX are given per year. Treatment is free of charge.Only 5 patients receive domiciliary treatment, but since 1958 we in Sweden have practised prophylactic treatment of boys (4–18 years old) with severe haemophilia A. At about 5-10 days interval they receive AHF in amounts sufficient to raise the AHF level to 40–50%. This regimen has reduced severe haemophilia to moderate. The joint score is identical with that found in moderate haemophilia in the same age groups. For treatment of patients with haemophilia A and haemophilia B complicated by inhibitors we have used a large dose of antigen (factor VIII or factor IX) combined with cyclophosphamide. In most cases this treatment produced satisfactory haemostasis for 5 to 30 days and prevented the secondary antibody rise.

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Accelerated Discovery of High-Refractive-Index Polyimides via First-Principles Molecular Modeling, Virtual High-Throughput Screening, and Data Mining

10.26434/chemrxiv.7670903.v1 ◽

2019 ◽

Author(s):

Mohammad Atif Faiz Afzal ◽

Mojtaba Haghighatlari ◽

Sai Prasad Ganesh ◽

Chong Cheng ◽

Johannes Hachmann

Keyword(s):

Data Mining ◽

Refractive Index ◽

High Throughput ◽

First Principles ◽

High Throughput Screening ◽

Large Scale ◽

Computational Study ◽

High Refractive Index ◽

Structural Features ◽

Learning Program

<div>We present a high-throughput computational study to identify novel polyimides (PIs) with exceptional refractive index (RI) values for use as optic or optoelectronic materials. Our study utilizes an RI prediction protocol based on a combination of first-principles and data modeling developed in previous work, which we employ on a large-scale PI candidate library generated with the ChemLG code. We deploy the virtual screening software ChemHTPS to automate the assessment of this extensive pool of PI structures in order to determine the performance potential of each candidate. This rapid and efficient approach yields a number of highly promising leads compounds. Using the data mining and machine learning program package ChemML, we analyze the top candidates with respect to prevalent structural features and feature combinations that distinguish them from less promising ones. In particular, we explore the utility of various strategies that introduce highly polarizable moieties into the PI backbone to increase its RI yield. The derived insights provide a foundation for rational and targeted design that goes beyond traditional trial-and-error searches.</div>

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Severe haemophilia a in a preterm girl with turner syndrome - a case report from the prenatal period to early infancy (part I)

Italian Journal of Pediatrics ◽

10.1186/s13052-020-00892-7 ◽

2020 ◽

Vol 46 (1) ◽

Author(s):

Agnieszka Berendt ◽

Monika Wójtowicz-Marzec ◽

Barbara Wysokińska ◽

Anna Kwaśniewska

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Turner Syndrome ◽

X Chromosome ◽

Diagnostic Procedures ◽

Haemophilia A ◽

Severe Haemophilia ◽

Preterm Children ◽

Initial Symptoms ◽

The Central Nervous System

Abstract Background Bleedings are more frequent in the population of preterm children than among those born at term, much less in older children. The reasons for such bleedings in preterms include plasma factor deficiencies, immaturity of small vessels in the germinal matrix region, prenatal hypoxia or sepsis. They affect the brain tissue, the gastrointestinal tract and the respiratory system, or are manifested by prolonged bleedings from injection sites. Haemophilia is a rare cause of haemorrhages in the neonatal period, and in the female population it is even seen as an extremely rare disorder. Its aetiology in girls is diverse: inheriting defective genes from their parents, skewed X inactivation or a single X chromosome. Case presentation The article presents a case of a preterm girl born in the 28th week of pregnancy, who was diagnosed with severe haemophilia A stemming from the absence of the X chromosome. The girl’s father is healthy, but her mother’s brother suffers from haemophilia. On the second day of the child’s life, a prolonged bleeding from the injection site was observed. A coagulation profile revealed prolonged APTT which pointed to haemophilia A diagnosis. Moreover, a marked clinical dysmorphy, female sex and a negative family history on the father’s side led the treating team to extend the diagnostic procedures to encompass karyotype evaluation. The girl was diagnosed with Turner syndrome. No bleeding to the central nervous system was observed during her hospital stay. Conclusions Preterm children belong to the risk group of bleeding into the central nervous system or haemorrhages in the course of sepsis. Rare causes of such bleedings should also be borne in mind, including haemophilia. The initial symptoms of haemophilia in preterm children occur in the first days of their lives, which is connected with a number of invasive procedures required in that period. Genetic conditions may coexist with one another. Arriving at one diagnosis does not mean one should abandon further diagnostic procedures in cases where additional atypical symptoms are present which do not match the clinical image of a primary disease.

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