| 1. |
- Gouw, Samantha C., et al.
(författare)
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F8 gene mutation type and inhibitor development in patients with severe hemophilia A: systematic review and meta-analysis
- 2012
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 119:12, s. 2922-2934
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Forskningsöversikt (refereegranskat)abstract
- This systematic review was designed to provide more precise effect estimates of inhibitor development for the various types of F8 gene mutations in patients with severe hemophilia A. The primary outcome was inhibitor development and the secondary outcome was high-titer-inhibitor development. Asystematic literature search was performed to include cohort studies published in peer-reviewed journals with data on inhibitor incidences in the various F8 gene mutation types and a mutation detection rate of at least 80%. Pooled odds ratios (ORs) of inhibitor development for different types of F8 gene mutations were calculated with intron 22 inversion as the reference. Data were included from 30 studies on 5383 patients, including 1029 inhibitor patients. The inhibitor risk in large deletions and nonsense mutations was higher than in intron 22 inversions (pooled OR = 3.6, 95% confidence interval [95% CI], 2.3-5.7 and OR = 1.4, 95% CI, 1.1-1.8, respectively), the risk in intron 1 inversions and splice-site mutations was equal (pooled OR = 0.9; 95% CI, 0.6-1.5 and OR = 1.0; 95% CI, 0.6-1.5), and the risk in small deletions/insertions and missense mutations was lower (pooled OR = 0.5; 95% CI, 0.4-0.6 and OR = 0.3; 95% CI, 0.2-0.4, respectively). The relative risks for developing high titer inhibitors were similar. (Blood. 2012;119(12):2922-2934)
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| 2. |
- Gouw, Samantha C., et al.
(författare)
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Factor VIII Products and Inhibitor Development in Severe Hemophilia A
- 2013
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Ingår i: New England Journal of Medicine. - 0028-4793. ; 368:3, s. 231-239
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Tidskriftsartikel (refereegranskat)abstract
- Background For previously untreated children with severe hemophilia A, it is unclear whether the type of factor VIII product administered and switching among products are associated with the development of clinically relevant inhibitory antibodies (inhibitor development). Methods We evaluated 574 consecutive patients with severe hemophilia A (factor VIII activity, <0.01 IU per milliliter) who were born between 2000 and 2010 and collected data on all clotting-factor administration for up to 75 exposure days. The primary outcome was inhibitor development, which was defined as at least two positive inhibitor tests with decreased in vivo recovery of factor VIII levels. Results Inhibitory antibodies developed in 177 of the 574 children (cumulative incidence, 32.4%); 116 patients had a high-titer inhibitory antibody, defined as a peak titer of at least 5 Bethesda units per milliliter (cumulative incidence, 22.4%). Plasma-derived products conferred a risk of inhibitor development that was similar to the risk with recombinant products (adjusted hazard ratio as compared with recombinant products, 0.96; 95% confidence interval [CI], 0.62 to 1.49). As compared with third-generation full-length recombinant products (derived from the full-length complementary DNA sequence of human factor VIII), second-generation full-length products were associated with an increased risk of inhibitor development (adjusted hazard ratio, 1.60; 95% CI, 1.08 to 2.37). The content of von Willebrand factor in the products and switching among products were not associated with the risk of inhibitor development. Conclusions Recombinant and plasma-derived factor VIII products conferred similar risks of inhibitor development, and the content of von Willebrand factor in the products and switching among products were not associated with the risk of inhibitor development. Second-generation full-length recombinant products were associated with an increased risk, as compared with third-generation products. (Funded by Bayer Healthcare and Baxter BioScience.)
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| 3. |
- Gouw, Samantha C., et al.
(författare)
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Intensity of factor VIII treatment and inhibitor development in children with severe hemophilia A: the RODIN study
- 2013
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 121:20, s. 4046-4055
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to examine the association of the intensity of treatment, ranging from high-dose intensive factor VIII (FVIII) treatment to prophylactic treatment, with the inhibitor incidence among previously untreated patients with severe hemophilia A. This cohort study aimed to include consecutive patients with a FVIII activity <0.01 IU/mL, born between 2000 and 2010, and observed during their first 75 FVIII exposure days. Intensive FVIII treatment of hemorrhages or surgery at the start of treatment was associated with an increased inhibitor risk (adjusted hazard ratio [aHR], 2.0; 95% confidence interval [CI], 1.3-3.0). High-dose FVIII treatment was associated with a higher inhibitor risk than low-dose FVIII treatment (aHR, 2.3; 95% CI, 1.0-4.8). Prophylaxis was only associated with a decreased overall inhibitor incidence after 20 exposure days of FVIII. The association with prophylaxis was more pronounced in patients with low-risk F8 genotypes than in patients with high-risk F8 genotypes (aHR, 0.61, 95% CI, 0.19-2.0 and aHR, 0.85, 95% CI, 0.51-1.4, respectively). In conclusion, our findings suggest that in previously untreated patients with severe hemophilia A, high-dosed intensive FVIII treatment increases inhibitor risk and prophylactic FVIII treatment decreases inhibitor risk, especially in patients with low-risk F8 mutations.
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| 4. |
- Gouw, Samantha C., et al.
(författare)
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Recombinant versus plasma-derived factor VIII products and the development of inhibitors in previously untreated patients with severe hemophilia A: the CANAL cohort study
- 2007
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 109:11, s. 4693-4697
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Tidskriftsartikel (refereegranskat)abstract
- It has been suggested that plasma-derived factor VIII products induce fewer inhibitors than recombinant factor VIII products. We investigated the relationship of factor VIII product type and switching between factor VIII products with the risk to develop inhibitors. This multicenter retrospective cohort study included 316 patients with severe hemophilia A born between 1990 and 2000. The outcome was clinically relevant inhibitor development, defined as the occurrence of at least 2 positive inhibitor titers with decreased recovery. The risk of inhibitor development was not clearly lower in plasma-derived compared with recombinant factor VIII products (relative risk [RR],. 0.8; 95% confidence interval [CI], 0.5-1.3). Among high-titer inhibitors, the possible reduction in risk was even less pronounced (RR, 0.9; CI, 0.5-1.5). Plasma-derived products with considerable quantities of von Willebrand factor (VWF) carried the same risk for inhibitor development as recombinant factor VIII products (RR, 1.0; CI, 0.6-1.6). Switching between factor VIII products did not increase the risk for inhibitors (RR, 1.1; CI, 0.6-1.8). In conclusion, our findings support neither the notion that plasma-derived factor VIII products with considerable concentrations of VWF confer a lower risk to develop inhibitory antibodies than recombinant factor VIII products, nor that switching between factor VIII product brands increases inhibitor risks in previously untreated patients with severe hemophilia A.
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| 5. |
- Volkers, Peter, et al.
(författare)
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Recombinant factor VIII products and inhibitor development in previously untreated patients with severe haemophilia A : Combined analysis of three studies
- 2019
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 25:3, s. 398-407
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Standard treatment of congenital haemophilia A is based on replacement therapy with coagulation factor VIII (FVIII) products. A major complication of FVIII therapy is the occurrence of IgG alloantibodies (inhibitors) that neutralize FVIII activity.AIM: The aim of the analysis was estimating the risk of high-titre inhibitor associated with the second-generation full-length product compared to third-generation full-length product and other recombinant FVIII (rFVIII).METHODS: We conducted a combined analysis of individual patient data from three large studies in previously untreated patients (PUPs) with severe haemophilia A.RESULTS: A total of 1109 PUPs were treated from 1993 to 2013 including 787 PUPs treated from 2004 onwards (primary analysis cohort). A total of 322 patients (29.0%) developed an inhibitor, of which 192 (17.3%) a high-titre inhibitor. In the primary analysis set, 29.9% of patients developed an inhibitor and 17.2% a high-titre inhibitor. The combined analysis indicated a lower risk of high-titre inhibitor development for the third-generation rFVIII product compared to the second-generation rFVIII product (primary analysis: adjusted hazard ratio (HR) = 0.72, 95% CI: 0.49 to 1.06). Adjusted HR for all inhibitor development was significantly lower for the third-generation product compared to the second-generation product.CONCLUSION: The trend of an increased risk of inhibitor development in PUPs for one recombinant product illustrates that extrapolation from one recombinant factor VIII product to other products might not be justified.
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| 6. |
- Berntorp, Erik, et al.
(författare)
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The second Team Haemophilia Education Meeting, 2016, Frankfurt, Germany
- 2017
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Ingår i: European Journal of Haematology. - : Wiley. - 0902-4441. ; 98:s85, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- The first Team Haemophilia Education (THE) Meeting was held on 7–8 May 2015 in Amsterdam, The Netherlands. It aimed to promote the optimal care of patients with haemophilia through education of the multidisciplinary treatment team. This was achieved by reviewing the latest developments in haemophilia management, considering how these can be implemented in the clinic to improve patient care and providing a platform for networking and debate for all haemophilia treatment team members. The second THE Meeting was held on 19–20 May in Frankfurt, Germany, and participants included doctors, nurses, physiotherapists, patient representatives and data management staff from 20 different countries. Topics covered the role of the multidisciplinary team in delivering the best haemophilia care, challenges in the management of haemophilia across Europe, available clotting factor treatments, future treatments and the use of genetics in advising carriers of haemophilia. This report is a summary of the key developments in haemophilia care presented by various investigators and healthcare professionals at THE Meeting 2016.
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| 7. |
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| 8. |
- Carcao, Manuel D., et al.
(författare)
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Correlation between phenotype and genotype in a large unselected cohort of children with severe hemophilia A
- 2013
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 121:19, s. 3946-3952
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Tidskriftsartikel (refereegranskat)abstract
- Phenotypic variability is well recognized in severe hemophilia A. A few studies, mainly in adults treated lifelong on demand, suggest that bleeding phenotype correlates with factor VIII gene (F8) mutation type. Because treatment regimens influence outcomes to a large extent, examining bleeding phenotype during the first years of life may be the most suitable way to define this variability. We set out to analyze the very early phenotypic expression of severe hemophilia A in 621 consecutively enrolled, well-characterized previously untreated patients and to correlate this with patients' F8 mutation. Detailed information was collected on bleeds and treatment of the first 75 exposure days or until inhibitor development. F8 mutation type was known for 531 patients; 402 had null mutations and 129 had non-null mutations. Considering only patients who had not started prophylaxis or developed an inhibitor before select bleeding events, we found that patients with null mutations experienced their first bleed and first joint bleed at younger median ages than patients with non-null mutations (9.7 vs 10.9 months and 13.8 vs 16.1 months, respectively). We conclude that F8 mutation type accounts for only a small component of the significant phenotypic variability found among patients with severe hemophilia A.
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| 9. |
- Fischer, Kathelijn, et al.
(författare)
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Intermediate- dose versus high-dose prophylaxis for severe hemophilia: comparing outcome and costs since the 1970s
- 2013
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 122:7, s. 1129-1136
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Tidskriftsartikel (refereegranskat)abstract
- Prophylactic treatment in severe hemophilia is very effective but is limited by cost issues. The implementation of 2 different prophylactic regimens in The Netherlands and Sweden since the 1970s may be considered a natural experiment. We compared the costs and outcomes of Dutch intermediate-and Swedish high-dose prophylactic regimens for patients with severe hemophilia (factor VIII/IX < 1 IU/dL) born between 1970 and 1994, using prospective standardized outcome assessment and retrospective collection of cost data. Seventy-eight Dutch and 50 Swedish patients, median age 24 years (range, 14-37 years), were included. Intermediate-dose prophylaxis used less factor concentrate (median: Netherlands, 2100 IU/kg per year [interquartile range (IQR), 1400-2900 IU/kg per year] vs Sweden, 4000 IU/kg per year [IQR, 3000-4900 IU/kg per year]); (P <.01). Clinical outcome was slightly inferior for the intermediate-dose regimen (P <.01) for 5-year bleeding (median, 1.3 [IQR, 0.8-2.7] vs 0 [IQR, 0.0-2.0] joint bleeds/y) and joint health (Haemophilia Joint Health Score > 10 of 144 points in 46% vs 11% of participants), although social participation and quality of life were similar. Annual total costs were 66% higher for high-dose prophylaxis (mean, 180 [95% confidence interval, 163 -196] 3 US$ 1000 for Dutch vs 298 [95% confidence interval, 271-325]) x US$ 1000 for Swedish patients; (P <.01). At group level, the incremental benefits of high-dose prophylaxis appear limited. At the patient level, prophylaxis should be tailored individually, and many patients may do well receiving lower doses of concentrate without compromising safety.
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| 10. |
- Globe, Dennis, et al.
(författare)
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Measuring patient-reported outcomes in haemophilia clinical research
- 2009
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 15:4, s. 843-852
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Forskningsöversikt (refereegranskat)abstract
- Patient-reported outcome (PRO) measures have been used to assess quality of life and health state preferences from the patient's perspective. However, they have not been fully utilized in haemophilia clinical practice and research. A series of meetings were convened to review and document the state of the art in PROs relevant to haemophilia. Experts developed a process for selection of measures and identified published measures of health-related quality of life (HRQoL) relevant to patients with haemophilia. These were synthesized and reviewed. Patient preference measures were also identified and reviewed. Although the majority of measures were developed for and validated in adults, several measures were identified for use in paediatric populations. This paper recommends an approach to the selection of PROs for application in haemophilia clinical research and practice and identifies several potential measures relevant for application in haemophilia clinical research and practice.
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