1
|
Janssen A, Smalbil L, Bennis FC, Cnossen MH, Mathôt RAA. A Generative and Causal Pharmacokinetic Model for Factor VIII in Hemophilia A: A Machine Learning Framework for Continuous Model Refinement. Clin Pharmacol Ther 2024; 115:881-889. [PMID: 38372445 DOI: 10.1002/cpt.3203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 01/25/2024] [Indexed: 02/20/2024]
Abstract
In rare diseases, such as hemophilia A, the development of accurate population pharmacokinetic (PK) models is often hindered by the limited availability of data. Most PK models are specific to a single recombinant factor VIII (rFVIII) concentrate or measurement assay, and are generally unsuited for answering counterfactual ("what-if") queries. Ideally, data from multiple hemophilia treatment centers are combined but this is generally difficult as patient data are kept private. In this work, we utilize causal inference techniques to produce a hybrid machine learning (ML) PK model that corrects for differences between rFVIII concentrates and measurement assays. Next, we augment this model with a generative model that can simulate realistic virtual patients as well as impute missing data. This model can be shared instead of actual patient data, resolving privacy issues. The hybrid ML-PK model was trained on chromogenic assay data of lonoctocog alfa and predictive performance was then evaluated on an external data set of patients who received octocog alfa with FVIII levels measured using the one-stage assay. The model presented higher accuracy compared with three previous PK models developed on data similar to the external data set (root mean squared error = 14.6 IU/dL vs. mean of 17.7 IU/dL). Finally, we show that the generative model can be used to accurately impute missing data (< 18% error). In conclusion, the proposed approach introduces interesting new possibilities for model development. In the context of rare disease, the introduction of generative models facilitates sharing of synthetic data, enabling the iterative improvement of population PK models.
Collapse
Affiliation(s)
- Alexander Janssen
- Department of Clinical Pharmacology, Hospital Pharmacy, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Louk Smalbil
- Quantitative Data Analytics Group, Department of Computer Science, VU Amsterdam, Amsterdam, The Netherlands
| | - Frank C Bennis
- Follow Me & Emma Neuroscience Group, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Amsterdam Reproduction and Development, Amsterdam, The Netherlands
| | - Marjon H Cnossen
- Department of Pediatric Hematology, Erasmus MC Sophia Children's Hospital, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Ron A A Mathôt
- Department of Clinical Pharmacology, Hospital Pharmacy, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
2
|
Goedhart TM, Bukkems LH, Zwagemaker AF, Coppens M, Fijnvandraat K, Schols SE, Schutgens RE, Eikenboom J, Heubel-Moenen FC, Ypma PF, Nieuwenhuizen L, Meijer K, Leebeek FW, Mathôt RA, Cnossen MH. Predictive performance of pharmacokinetic-guided prophylactic dosing of factor concentrates in hemophilia A and B. Res Pract Thromb Haemost 2024; 8:102397. [PMID: 38689619 PMCID: PMC11058079 DOI: 10.1016/j.rpth.2024.102397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Accepted: 03/18/2024] [Indexed: 05/02/2024] Open
Abstract
Background Pharmacokinetic (PK)-guided dosing is used to individualize factor (F)VIII and FIX replacement therapy. Objectives This study investigates the reliability and feasibility of PK-guided prophylactic dosing of factor concentrates in hemophilia A and B. Methods In this multicenter, prospective cohort study, people of all ages with hemophilia received prophylactic treatment with factor concentrates based on individual PK parameters. During follow-up, at least 4 measured FVIII/FIX levels per patient were compared with corresponding predicted levels obtained by Bayesian forecasting. Predictive performance was defined as adequate when ≥80% of measured FVIII/FIX levels were within ±25% of prediction (relative error). Additionally, mean absolute error and mean error were calculated. In post hoc analyses, predictive performance was assessed allowing maximum absolute errors of 1 (trough), 5 (mid), and 15 (peak) IU/dL. Five-point scale questionnaires addressed feasibility of PK guidance. Results We included 50 patients (median age, 19 years; range: 2-72 years). Median follow-up was 36 weeks. Seventy-one percent of levels (58% trough, 83% mid, and 80% peak) were within ±25% of prediction. Mean absolute errors were 0.8 (trough), 2.0 (mid), and 8.6 (peak) IU/dL. In post hoc analyses, 81% (trough), 96% (mid), and 82% (peak) of levels were within set limits. Patients reported low burden and high satisfaction. Conclusion PK-guided dosing was reliable according to post hoc analyses, based on low absolute errors that were regarded as clinically irrelevant in most cases. The predefined predictive performance was achieved in mid and peak factor levels but not in trough factor levels due to measurement inaccuracy. PK guidance also seemed feasible.
Collapse
Affiliation(s)
- Tine M.H.J. Goedhart
- Department of Pediatric Hematology and Oncology, Erasmus MC Sophia Children’s Hospital, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Laura H. Bukkems
- Department of Clinical Pharmacology—Hospital Pharmacy, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Anne-Fleur Zwagemaker
- Department of Pediatric Hematology, Amsterdam UMC, University of Amsterdam, Emma Children’s Hospital, Amsterdam, the Netherlands
| | - Michiel Coppens
- Department of Vascular Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Pulmonary Hypertension & Thrombosis, Amsterdam, the Netherlands
| | - Karin Fijnvandraat
- Department of Pediatric Hematology, Amsterdam UMC, University of Amsterdam, Emma Children’s Hospital, Amsterdam, the Netherlands
| | - Saskia E.M. Schols
- Department of Hematology, Radboud University Medical Center, Nijmegen, the Netherlands
- Hemophilia Treatment Center Nijmegen-Eindhoven-Maastricht, the Netherlands
| | - Roger E.G. Schutgens
- Van Creveldkliniek, Center for Benign Haematology, Thrombosis and Haemostasis, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Jeroen Eikenboom
- Department of Internal Medicine, Division of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
| | | | - Paula F. Ypma
- Department of Hematology, Haga Hospital, the Hague, the Netherlands
| | | | - Karina Meijer
- Department of Hematology, University Medical Center Groningen, Groningen, the Netherlands
| | - Frank W.G. Leebeek
- Department of Hematology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Ron A.A. Mathôt
- Department of Clinical Pharmacology—Hospital Pharmacy, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Marjon H. Cnossen
- Department of Pediatric Hematology and Oncology, Erasmus MC Sophia Children’s Hospital, University Medical Center Rotterdam, Rotterdam, the Netherlands
| |
Collapse
|
3
|
Guillet B, Hassoun A, Wibaut B, Harroche A, Biron-Andréani C, Repesse Y, d'Oiron R, Tardy B, Pan Petesch B, Chamouni P, Gay V, Fouassier M, Pouplard C, Martin C, Catovic H, Delavenne X. A French Real-World Evidence Study Evaluating the Efficacy, Safety, and Pharmacokinetic Parameters of rVIII-SingleChain in Patients with Hemophilia A Receiving Prophylaxis. Thromb Haemost 2023; 123:490-500. [PMID: 36758611 PMCID: PMC10113037 DOI: 10.1055/s-0043-1761449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
BACKGROUND rVIII-SingleChain is a recombinant factor VIII (FVIII) with increased binding affinity to von Willebrand factor compared with other FVIII products. rVIII-SingleChain is indicated for the treatment and prevention of bleeding episodes in patients with hemophilia A. OBJECTIVES To collect real-world evidence data from patients treated with rVIII-SingleChain to confirm the efficacy and safety established in the clinical trial program and carry out a population pharmacokinetic (PK) analysis. PATIENTS/METHODS This interim analysis includes data, collected between January 2018 - September 2021, from patients treated with rVIII-SingleChain prophylaxis at French Hemophilia Treatment centers. Data on annualized bleeding rates, dosing frequency, and consumption before and after switching to rVIII-SingleChain were recorded. A population PK analysis was also conducted to estimate PK parameters. RESULTS Overall, 43 patients switched to prophylaxis with rVIII-SingleChain either from a previous prophylaxis regimen or from on-demand treatment. Following the switch to rVIII-SingleChain, patients maintained excellent bleed control. After switching to rVIII-SingleChain, most patients maintained or reduced their regimen. Interestingly, a majority of patients treated >2 ×/weekly with a standard half-life FVIII reduced both injection frequency and FVIII consumption with rVIII-SingleChain. A PK analysis revealed a lower clearance of rVIII-SingleChain (1.9 vs. 2.1 dL/h) and a longer half-life both in adolescents/adults (n = 28) and pediatric (n = 6) patients (15.5 and 11.9 hours, respectively vs. 14.5 and 10.3 hours) than previously reported. CONCLUSIONS Patients who switched to rVIII-SingleChain prophylaxis demonstrated excellent bleed control and a reduction in infusion frequency. A population PK analysis revealed improved PK parameters compared with those reported in the clinical trial.
Collapse
Affiliation(s)
- Benoit Guillet
- Haemophilia Treatment Center, University Hospital, Rennes, France.,Univ Rennes, CHU Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | - Abel Hassoun
- Haemophilia Treatment Center, Simone Veil Hospital, GH Eaubonne-Montmorency, France
| | - Bénédicte Wibaut
- Haemophilia Treatment Centre, National Reference Willebrand Centre, University Hospital, Lille, France
| | - Annie Harroche
- Department of Hematology, Haemophilia Treatment Centre, University Hospital Necker Enfants Malades, Paris, France
| | | | - Yohan Repesse
- Haematology Laboratory and Haemophilia Reference Centre, Centre Hospitalier Universitaire de Caen, Caen, France
| | - Roseline d'Oiron
- CRH, CRC-MHC (Centre de Référence de l'Hémophilie, Centre de Ressource et de Compétence des Maladies Hémorragiques Constitutionnelles), Hôpital Bicêtre, AP-HP, Université Paris-Saclay, Paris, France.,HITh, UMR_S1176, INSERM, Université Paris-Saclay, Le Kremlin Bicêtre, France
| | - Brigitte Tardy
- Haemophilia Treatment Center, University Hospital, Saint-Etienne, France.,Inserm CIC 1408, Saint-Etienne University Hospital Center, Saint-Etienne, France
| | - Brigitte Pan Petesch
- Haemophilia Treatment Center, Morvan University Hospital, Saint-Etienne Brest, France
| | - Pierre Chamouni
- Haemophilia Treatment Center, University Hospital, Rouen, France
| | - Valérie Gay
- Haemophilia Treatment Center, Hospital, Chambery, France
| | - Marc Fouassier
- Haemophilia Treatment Center, Hôtel-Dieu University Hospital, Nantes, France
| | | | | | | | - Xavier Delavenne
- INSERM, UMR 1059, Dysfonction Vasculaire et de l'Hémostase, Université de Lyon, Saint Etienne, France.,Laboratoire de Pharmacologie - Toxicologie, CHU de Saint-Etienne, Saint-Etienne, France
| |
Collapse
|
4
|
Uster DW, Chowdary P, Riddell A, Garcia C, Aradom E, Musarara M, Wicha SG. Dosing for Personalized Prophylaxis in Hemophilia A Highly Varies on the Underlying Population Pharmacokinetic Models. Ther Drug Monit 2022; 44:665-673. [PMID: 35358115 DOI: 10.1097/ftd.0000000000000983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 02/21/2022] [Indexed: 01/19/2023]
Abstract
BACKGROUND Model-informed personalized prophylaxis with factor VIII (FVIII) replacement therapy aimed at higher trough levels is becoming indispensable for patients with severe hemophilia A. This study aimed to identify the most suitable population pharmacokinetic (PK) models for personalized prophylaxis using various FVIII products and 2 clinical assays and to implement the most suitable one in open-access software. METHODS Twelve published population PK models were systematically compared to predict the time above target (TaT) for a reference dosing occasion. External validation was performed using a 5-point PK data from 39 adult patients with hemophilia A with FVIII measured by chromogenic substrate (CSA) and 1-stage assays (OSAs) using NONMEM under 3 different conditions: a priori (with all FVIII samples blinded), a posteriori (with 1 trough sample), and general model fit (with all FVIII samples including the reference dosing occasion provided). RESULTS On average, the baseline covariate models overpredicted TaT (a priori; bias -3.8 hours to 49.6 hours). When additionally including 1 previous trough FVIII sample before the reference dosing occasion (a posteriori), only 50% of the models improved in bias (-1.0 hours to 36.5 hours) and imprecision (22.4 hours and 60.7 hours). Using all the time points (general model fit), the models accurately predicted (individual TaT less than ±12 hours compared with the reference) 62%-90% and 33%-74% of the patients using CSA and OSA data, respectively. Across all scenarios, predictions using CSA data were more accurate than those using the OSA data. CONCLUSIONS One model performed best across the population (bias: -3.8 hours a priori, -1.0 hours a posteriori , and 0.6 hours general model fit ) and acceptably predicted 44% (a priori) to 90% ( general model fit ) of the patients. To allow the community-based evaluation of patient-individual FVIII dosing, this model was implemented in the open-access model-informed precision dosing software "TDMx."
Collapse
Affiliation(s)
- David W Uster
- Department of Clinical Pharmacy, Institute of Pharmacy, University of Hamburg, Hamburg, Germany ; and
| | - Pratima Chowdary
- Katharine Dormandy Haemophilia and Thrombosis Centre, Royal Free Hospital, London, United Kingdom
| | - Anne Riddell
- Katharine Dormandy Haemophilia and Thrombosis Centre, Royal Free Hospital, London, United Kingdom
| | - Cecilia Garcia
- Katharine Dormandy Haemophilia and Thrombosis Centre, Royal Free Hospital, London, United Kingdom
| | - Elsa Aradom
- Katharine Dormandy Haemophilia and Thrombosis Centre, Royal Free Hospital, London, United Kingdom
| | - Molly Musarara
- Katharine Dormandy Haemophilia and Thrombosis Centre, Royal Free Hospital, London, United Kingdom
| | - Sebastian G Wicha
- Department of Clinical Pharmacy, Institute of Pharmacy, University of Hamburg, Hamburg, Germany ; and
| |
Collapse
|
5
|
Janssen A, Hoogendoorn M, Cnossen MH, Mathôt RAA. Application of SHAP values for inferring the optimal functional form of covariates in pharmacokinetic modeling. CPT Pharmacometrics Syst Pharmacol 2022; 11:1100-1110. [PMID: 38100100 PMCID: PMC9381890 DOI: 10.1002/psp4.12828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 05/14/2022] [Accepted: 05/18/2022] [Indexed: 12/12/2022] Open
Abstract
In population pharmacokinetic (PK) models, interindividual variability is explained by implementation of covariates in the model. The widely used forward stepwise selection method is sensitive to bias, which may lead to an incorrect inclusion of covariates. Alternatives, such as the full fixed effects model, reduce this bias but are dependent on the chosen implementation of each covariate. As the correct functional forms are unknown, this may still lead to an inaccurate selection of covariates. Machine learning (ML) techniques can potentially be used to learn the optimal functional forms for implementing covariates directly from data. A recent study suggested that using ML resulted in an improved selection of influential covariates. However, how do we select the appropriate functional form for including these covariates? In this work, we use SHapley Additive exPlanations (SHAP) to infer the relationship between covariates and PK parameters from ML models. As a case-study, we use data from 119 patients with hemophilia A receiving clotting factor VIII concentrate peri-operatively. We fit both a random forest and a XGBoost model to predict empirical Bayes estimated clearance and central volume from a base nonlinear mixed effects model. Next, we show that SHAP reveals covariate relationships which match previous findings. In addition, we can reveal subtle effects arising from combinations of covariates difficult to obtain using other methods of covariate analysis. We conclude that the proposed method can be used to extend ML-based covariate selection, and holds potential as a complete full model alternative to classical covariate analyses.
Collapse
Affiliation(s)
- Alexander Janssen
- Department of Clinical Pharmacology, Hospital PharmacyAmsterdam University Medical CenterAmsterdamThe Netherlands
| | - Mark Hoogendoorn
- Quantitative Data Analytics Group, Department of Computer Science, Vrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Marjon H. Cnossen
- Department of Pediatric Hematology, Erasmus MC Sophia Children’s HospitalErasmus University Medical CenterRotterdamThe Netherlands
| | - Ron A. A. Mathôt
- Department of Clinical Pharmacology, Hospital PharmacyAmsterdam University Medical CenterAmsterdamThe Netherlands
| | | |
Collapse
|
6
|
Goedhart TM, Bukkems LH, Coppens M, Fijnvandraat KJ, Schols SE, Schutgens RE, Eikenboom J, Heubel-Moenen FC, Ypma PF, Nieuwenhuizen L, Meijer K, Leebeek FWG, Mathôt RA, Cnossen MH. Design of a Prospective Study on Pharmacokinetic-Guided Dosing of Prophylactic Factor Replacement in Hemophilia A and B (OPTI-CLOT TARGET Study). TH OPEN 2022; 6:e60-e69. [PMID: 35280975 PMCID: PMC8913178 DOI: 10.1055/a-1760-0105] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 01/11/2022] [Indexed: 11/11/2022] Open
Abstract
In resource-rich countries, almost all severe hemophilia patients receive prophylactic replacement therapy with factor concentrates to prevent spontaneous bleeding in joints and muscles to decrease the development of arthropathy and risk of long-term disability. Pharmacokinetic (PK)-guided dosing can be applied to individualize factor replacement therapy, as interindividual differences in PK parameters influence factor VIII (FVIII) and FIX activity levels. PK-guided dosing may therefore lead to more optimal safeguarding of FVIII/FIX levels during prophylaxis and on demand treatment. The OPTI-CLOT TARGET study is a multicenter, nonrandomized, prospective cohort study that aims to investigate the reliability and feasibility of PK-guided prophylactic dosing of factor concentrates in hemophilia-A and -B patients in daily clinical practice. At least 50 patients of all ages on prophylactic treatment using standard half-life (SHL) and extended half-life (EHL) factor concentrates will be included during 9 months and will receive PK-guided treatment. As primary endpoint, a minimum of four FVIII/FIX levels will be compared with FVIII/FIX levels as predicted by Bayesian forecasting. Secondary endpoints are the association of FVIII and FIX levels with bleeding episodes and physical activity, expectations and experiences, economic analyses, and optimization of population PK models. This study will lead to more insight in the reliability and feasibility of PK-guided dosing in hemophilia patients. Moreover, it will contribute to personalization of treatment by greater knowledge of dosing regimens needed to prevent and treat bleeding in the individual patient and provide evidence to more clearly associate factor activity levels with bleeding risk.
Collapse
Affiliation(s)
- Tine M.H.J. Goedhart
- Department of Pediatric Hematology and Oncology, Erasmus MC Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Laura H. Bukkems
- Department of Clinical Pharmacology - Hospital Pharmacy, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Michiel Coppens
- Department of Vascular Medicine, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Karin J. Fijnvandraat
- Department of Pediatric Hematology, Amsterdam UMC, Emma Children's Hospital, University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
| | - Saskia E.M. Schols
- Department of Hematology, Radboud University Medical Center, Nijmegen, and the Hemophilia Treatment Center Nijmegen-Eindhoven-Maastricht, The Netherlands
| | | | - Jeroen Eikenboom
- Department of Internal Medicine, Division of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Paula F. Ypma
- Department of Hematology, Haga Hospital, The Hague, The Netherlands
| | - L. Nieuwenhuizen
- Department of Internal Medicine, Maxima Medical Center, Veldhoven, The Netherlands
| | - K. Meijer
- Department of Hematology, University Medical Center Groningen, Groningen, The Netherlands
| | - Frank W. G. Leebeek
- Department of Hematology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Ron A.A. Mathôt
- Department of Clinical Pharmacology - Hospital Pharmacy, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Marjon H. Cnossen
- Department of Pediatric Hematology and Oncology, Erasmus MC Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, The Netherlands
| |
Collapse
|
7
|
Singkham N, Punyawudho B, Yu M, Cheng S, Chen S, Chang H, Chen C, Hsiao C, Hou J, Fang Y, Wang H, Lin J, Yu LH, Chen Y. Influence of blood group and von Willebrand factor on population pharmacokinetics and dose individualization of recombinant factor VIII in Taiwanese patients with haemophilia A. Haemophilia 2022; 28:230-238. [DOI: 10.1111/hae.14493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 01/03/2022] [Accepted: 01/04/2022] [Indexed: 12/15/2022]
Affiliation(s)
- Noppaket Singkham
- Department of Pharmaceutical Care, School of Pharmaceutical Sciences University of Phayao Phayao Thailand
| | - Baralee Punyawudho
- Department of Pharmaceutical Care, Faculty of Pharmacy Chiang Mai University Chiang Mai Thailand
| | - Ming‐Sun Yu
- Division of Hematology Conde S. Januário Hospital Macau China
| | - Shin‐Nan Cheng
- Hemophilia and Rare Disease Treatment Center Tungs’ Taichung MetroHarbor Hospital Taichung Taiwan
| | - Shu‐Huey Chen
- Department of Pediatrics, School of Medicine, College of Medicine Taipei Medical University Taipei Taiwan
- Department of Pediatrics, Shuang Ho Hospital, Ministry of Health and Welfare Taipei Medical University Taipei Taiwan
| | - Hung Chang
- Division of Hematology and Oncology Chang Gung Memorial Hospital at Linkou Taoyuan Taiwan
| | - Chih‐Cheng Chen
- Division of Hematology and Oncology, Department of Medicine Chang Gung Memorial Hospital, Chiayi Branch Chiayi Taiwan
- College of Medicine Chang Gung University Tao‐Yuan Taiwan
| | - Chih‐Cheng Hsiao
- Division of Hematology/Oncology, Department of Pediatrics Kaohsiung Chang Gung Memorial Hospital Kaohsiung Taiwan
- College of Medicine Chang Gung University Kaohsiung Taiwan
| | - Jen‐Yin Hou
- Division of Pediatric Hematology‐Oncology MacKay Children's Hospital Taipei Taiwan
| | - Yi‐Ping Fang
- School of Pharmacy, College of Pharmacy Kaohsiung Medical University Kaohsiung Taiwan
- Department of Medical Research Kaohsiung Medical University Hospital Kaohsiung Taiwan
- Regeneration Medicine and Cell Therapy Research Center, College of Medicine Kaohsiung Medical University Kaohsiung Taiwan
| | | | - Jia‐Hong Lin
- Medical Affairs Department Panco Healthcare Taipei Taiwan
| | | | - Yeu‐Chin Chen
- Division of Hematology and Oncology, Department of Medicine Tri‐Service General Hospital, National Defense Medical Center Taipei Taiwan
| |
Collapse
|
8
|
Abstract
Efmoroctocog alfa (Elocta®, Eloctate®, Eloctate™), an extended half-life (EHL) recombinant factor VIII (rFVIII)-Fc fusion protein, is approved for the treatment and prophylaxis of bleeding in patients with haemophilia A. The efficacy of efmoroctocog alfa in the prevention and treatment of bleeding in previously treated patients (PTPs) and previously untreated patients (PUPs) with severe haemophilia A has been demonstrated in phase III studies; this includes its use in the perioperative setting (in PTPs). Furthermore, the effectiveness of efmoroctocog alfa in clinical practice has been confirmed in numerous real-world studies; compared with conventional, standard half-life (SHL) FVIII products, prophylaxis with this EHL FVIII product achieved similar or reduced bleeding rates with fewer injections. Efmoroctocog alfa was generally well tolerated; inhibitors occurred in approximately one-third of PUPs in a phase III study. Efmoroctocog alfa is an established and effective EHL FVIII replacement therapy for the management of haemophilia A. Compared with SHL FVIII products, EHL FVIII products such as efmoroctocog alfa have the potential to optimise prophylactic outcomes by decreasing the burden of treatment or increasing the level of bleed protection.
Collapse
Affiliation(s)
- James E Frampton
- Springer Nature, Private Bag 65901, Mairangi Bay, Auckland, 0754, New Zealand.
| |
Collapse
|
9
|
Population pharmacokinetic modeling of factor concentrates in hemophilia: an overview and evaluation of best practice. Blood Adv 2021; 5:4314-4325. [PMID: 34496017 PMCID: PMC8945640 DOI: 10.1182/bloodadvances.2021005096] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 06/10/2021] [Indexed: 12/30/2022] Open
Abstract
The accuracy of pharmacokinetic (PK)-guided dosing depends on the clinical and laboratory data used to construct a population PK model, as well as the patient’s individual PK profile. This review provides a detailed overview of data used for published population PK models for factor VIII (FVIII) and factor IX (FIX) concentrates, to support physicians in their choices of which model best suits each patient. Furthermore, to enhance detailed data collection and documentation, we do suggestions for best practice. A literature search was performed; publications describing prophylactic population PK models for FVIII and FIX concentrates based on original patient data and constructed using nonlinear mixed-effect modeling were included. The following data were collected: detailed demographics, type of product, assessed and included covariates, laboratory specifications, and validation of models. Included models were scored according to our recommendations for best practice, specifically scoring the quality of data documentation as reported. Respectively, 20 models for FVIII and 7 for FIX concentrates were retrieved. Although most models (22/27) included pediatric patients, only 4 reported detailed demographics. The wide range of body weights suggested that overweight and obese adults were represented. Twenty-six models reported the assay applied to measure factor levels, whereas only 16 models named reagents used. Eight models were internally validated using a data subset. This overview presents detailed information on clinical and laboratory data used for published population PK models. We provide recommendations on data collection and documentation to increase the reliability of PK-guided prophylactic dosing of factor concentrates in hemophilia A and B.
Collapse
|
10
|
Favorable Pharmacokinetic Characteristics of Extended-Half-Life Recombinant Factor VIII BAY 94-9027 Enable Robust Individual Profiling Using a Population Pharmacokinetic Approach. Clin Pharmacokinet 2021; 59:605-616. [PMID: 31749076 PMCID: PMC7217814 DOI: 10.1007/s40262-019-00832-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Background Prophylaxis with factor VIII (FVIII) should be individualized based on patient characteristics, including FVIII pharmacokinetics. Population pharmacokinetic (popPK) modeling simplifies pharmacokinetic studies by obviating the need for multiple samples. Objective The objective of this study was to characterize the pharmacokinetics and inter-individual variability (IIV) of BAY 94-9027 in relation to patient characteristics in support of a popPK-tailored approach, including identifying the optimal number and timing of pharmacokinetic samples. Methods Pharmacokinetic samples from 198 males (aged 2‒62 years) with severe hemophilia A, enrolled in BAY 94-9027 clinical trials, were analyzed. Baseline age, height, weight, body mass index, lean body weight (LBW), von Willebrand factor (VWF) level, and race were evaluated. A popPK model was developed and used to simulate pharmacokinetic endpoints difficult to observe from measured FVIII levels, including time to maintain FVIII levels above 1, 3, and 5 IU/dL after different BAY 94-9027 doses. Results A one-compartment model adequately described BAY 94-9027 pharmacokinetics. Clearance and central volume of distribution were significantly associated with LBW; clearance was inversely correlated with VWF. Due to the monophasic pharmacokinetics and well-understood IIV sources, identification of patient pharmacokinetics was achievable with sparse blood sampling. Median predicted time to maintain FVIII levels > 1 IU/dL in patients aged ≥ 12 years ranged from 120.1 to 127.2 h after single BAY 94-9027 doses of 45‒60 IU/kg. Conclusions This analysis evaluated the pharmacokinetics of BAY 94-9027 and its sources of IIV. Using the model, determination of individual patient pharmacokinetics was possible with few FVIII samples, and a sparse sampling design to support pharmacokinetic-guided dosing was identified.
Collapse
|
11
|
Recombinant Factor VIII Fc Fusion Protein (rFVIIIFc) in Real Life: One-Year Clinical and Economic Outcomes. Drugs Real World Outcomes 2021; 8:527-535. [PMID: 34170499 PMCID: PMC8605945 DOI: 10.1007/s40801-021-00259-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2021] [Indexed: 01/19/2023] Open
Abstract
Background Recombinant factor VIII Fc fusion protein (rFVIIIFc) is the first extended half-life (EHL) recombinant clotting factor with marketing authorization; it has been available in France since October 2016. However, data and literature about rFVIIIFc in clinical practice are scarce. Objective We propose a 1-year clinical and economic outcome evaluation in patients with hemophilia A taking into consideration treatment adherence. Patients and methods We reviewed the diaries of all patients treated with rFVIIIFc at Marseille Hemophilia Center for 1 year. All the data were related to the patients’ infusion (i.e., annual number of infusions, weekly dose/kg, and annual consumption) and bleeding reports. The clotting factor costs were considered, whereas additional costs (e.g., infusion devices and nurse intervention) were neglected. Results A total of 34 patients were evaluated. Their median age was 18 years (IQR = 18). Treatment adherence was observed in 62% for FVIII and 66% for rFVIIIFc. The analysis revealed a negligible decrease in the annual clotting factor consumption following the switch (− 2%, p = 0.7339). These data were combined with a significant reduction in the annual number of infusion (− 22.5%, median = 138.5, IQR = 65.8 for FVIII; median = 105, IQR = 24 for rFVIIIFc, p < 0.0001) and bleeding (− 50%, median = 5, IQR = 7.5 for FVIII; median = 1, IQR = 4 for rFVIIIFc, p < 0.0001). With regard to the cost, a decreasing trend was observed (− 8%, p = 0.1300). Conclusion The analysis in a real-life setting revealed that the input of switches toward rFVIIIFc in different treatment (age of patients and regimen) patterns seems to corroborate previous studies. The results suggest that switches have a beneficial effect in terms of efficacy, clotting factor consumption, and cost.
Collapse
|
12
|
Chelle P, Yeung CHT, Croteau SE, Lissick J, Balasa V, Ashburner C, Park YS, Bonanad S, Megías-Vericat JE, Nagao A, Wynn T, Corrales-Medina F, Tran H, Sharathkumar A, Chitlur M, Sarmiento S, Edginton A, Iorio A. Development and Validation of a Population-Pharmacokinetic Model for Rurioctacog Alfa Pegol (Adynovate ®): A Report on Behalf of the WAPPS-Hemo Investigators Ad Hoc Subgroup. Clin Pharmacokinet 2021; 59:245-256. [PMID: 31435896 DOI: 10.1007/s40262-019-00809-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND AND OBJECTIVE Rurioctacog alfa pegol (Adynovate) is a modified recombinant factor VIII concentrate used for treating hemophilia A. Aiming to improve treatment tailoring on the Web-Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo) platform for patients of all ages treated with Adynovate, we have developed and evaluated a population pharmacokinetic (PopPK) model. On the platform, PopPK models are used as priors for Bayesian forecasting that derive individual PK of hemophilia patients and are subsequently used for personalized dose regimen design. METHODS Factor activity measurements and demographic covariate data from patients infused with Adynovate were extracted from the WAPPS-Hemo database. Evaluations testing the appropriateness of Bayesian forecasting included 10-fold cross validation, a limited sampling analysis (LSA), and an external evaluation using additional independent data extracted from the WAPPS-Hemo database at a later date. RESULTS The model was constructed using 650 plasma factor activity observations (555 one stage assay and 95 chromogenic assay - 4.6% below limit of quantification) measured in 154 patients from 36 hemophilia centres. A two-compartment model including between subject variability on clearance and central volume was selected as the base model. Covariates were fat free mass on clearance and central volume, age on clearance and assay type on activity. The final model was well-suited to predict PK parameters of new individuals (n = 26) from sparse observations. CONCLUSIONS The development of a PopPK model for Adynovate using real-world data increases the covariate space (e.g. age) beyond what is possible from clinical trial data. This model is available on the WAPPS-Hemo platform for tailoring treatment in hemophilia A patients.
Collapse
Affiliation(s)
- Pierre Chelle
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada
| | - Cindy H T Yeung
- Department of Health Research Methods, Evidence, and Impact, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada
| | - Stacy E Croteau
- Boston Children's Hospital/Harvard Medical School, Boston, MA, USA
| | | | | | | | - Young Shil Park
- Kyung Hee University Hospital at Gangdong, Seoul, Republic of Korea
| | | | | | | | - Tung Wynn
- University of Florida, Gainesville, FL, USA
| | | | - Huyen Tran
- Ronald Sawers Haemophilia Treatment Centre, Melbourne, VIC, Australia
| | - Anjali Sharathkumar
- University of Iowa Carver College of Medicine, Stead Family Department of Pediatrics, University of Iowa Children's Hospital, Iowa City, IA, USA
| | | | | | - Andrea Edginton
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada
| | - Alfonso Iorio
- Department of Health Research Methods, Evidence, and Impact, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada. .,McMaster Bayer Endowed Chair for Clinical Epidemiology of Congenital Bleeding Disorders, Department of Medicine, McMaster University, Hamilton, ON, Canada.
| |
Collapse
|
13
|
Katragadda S, Neelakantan S, Diao L, Wong N. Population Pharmacokinetic Analysis of Recombinant Factor VIII Fc Fusion Protein in Subjects With Severe Hemophilia A: Expanded to Include Pediatric Subjects. J Clin Pharmacol 2021; 61:889-900. [PMID: 33719084 DOI: 10.1002/jcph.1854] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 03/04/2021] [Indexed: 01/19/2023]
Abstract
Recombinant factor VIII Fc fusion protein (rFVIIIFc) has been indicated for adults and children with hemophilia A. The objective of this article was to build a population pharmacokinetic (PK) model using adult and pediatric data sets and explore relevant dosing scenarios across all ages. The activity-time profiles of rFVIIIFc from 3 clinical studies (all trials registered at https://www.clinicaltrials.gov: NCT01027377, NCT01181128, and NCT01458106) were characterized, and covariates that determine variability of rFVIIIFc PK in children and adults were identified and implemented. Data sets were pooled to estimate population PK parameters. Simulations were conducted to generate activity-time profiles at steady state (SS). The proportion of subjects maintaining SS trough >1 and >3 IU/dL and time >10 IU/dL were estimated. The rFVIIIFc model was a two-compartment model that identified weight and von Willebrand factor as significant covariates. Model-predicted SS peaks and troughs of rFVIIIFc activity-time profiles confirmed the necessity of modifying dosing in pediatric subjects. The model also predicted that the average subject in the adult and adolescent group dosed with 40 IU/kg every 2 days maintained factor VIII activity >10 IU/dL for the entire duration. Children aged <6 years and aged 6 to <12 years receiving this dose maintained factor VIII activity of >10 IU/dL for nearly two-thirds and three-quarters of their time, respectively. In conclusion, these population PK analyses characterize activity-time profiles for rFVIIIFc among pediatric and adult subjects. The model was used for simulation of clinically relevant dosing scenarios, which can provide better protection and better clinical outcomes.
Collapse
Affiliation(s)
| | | | - Lei Diao
- EpimAb Biotherapeutics, Shanghai, China
| | | |
Collapse
|
14
|
McEneny-King A, Chelle P, Goggans MH, Barker PJ, Jacobs TW, Neufeld EJ, Reiss UM, Panetta JC. Limited sampling strategies for accurate determination of extended half-life factor VIII pharmacokinetics in severe haemophilia A patients. Haemophilia 2021; 27:408-416. [PMID: 33742733 DOI: 10.1111/hae.14288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 02/13/2021] [Accepted: 02/15/2021] [Indexed: 01/19/2023]
Abstract
BACKGROUND Extended half-life (EHL) factor VIII (FVIII) products may decrease the burden of prophylactic treatment in haemophilia A by reducing infusion frequency. However, these products still exhibit wide inter-patient variability and benefit from pharmacokinetic (PK) tailoring. OBJECTIVE Identify limited sampling strategies for rFVIIIFc, an EHL FVIII product, that produce accurate estimates of PK parameters and relevant troughs. METHODS We performed a limited sampling analysis on simulated populations of adults, adolescents, and children based on published population PK data. Sampling strategies were evaluated by comparing the error in estimates of half-life, clearance, and trough levels, to a full 6-sample design. Furthermore, we assessed the impact of incorporating knowledge about prior doses, and the day of the PK study within the regimen. We also evaluated the potential inappropriate dose adjustment rate (IDAR) among the modelled sampling strategies. RESULTS Many sampling strategies, including several 2-sample designs, accurately predicted the PK and exposure measures (median absolute error <10%). When samples are only collected during a single visit (i.e., predose + peak), inclusion of prior dose information reduces median half-life error from >20% to ~5% for adults/adolescents. In this same scenario, appropriate scheduling of the PK study decreases likelihood of unmeasurable predose samples, reducing median error on the 72-h trough from 25% to <12% in the youngest population. CONCLUSIONS The PK of rFVIIIFc can be accurately estimated using only peak and trough samples, provided that knowledge of prior doses is incorporated and the PK study is planned on an appropriate day within the dosing regimen.
Collapse
Affiliation(s)
| | - Pierre Chelle
- School of Pharmacy, University of Waterloo, Kitchener, Ontario, Canada
| | - Margaret H Goggans
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Patricia J Barker
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Timothy W Jacobs
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Ellis J Neufeld
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Ulrike M Reiss
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - John C Panetta
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| |
Collapse
|
15
|
Preijers T, Schütte LM, Kruip MJHA, Cnossen MH, Leebeek FWG, van Hest RM, Mathôt RAA. Population Pharmacokinetics of Clotting Factor Concentrates and Desmopressin in Hemophilia. Clin Pharmacokinet 2020; 60:1-16. [PMID: 32936401 PMCID: PMC7808974 DOI: 10.1007/s40262-020-00936-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Hemophilia A and B are bleeding disorders caused by a deficiency of clotting factor VIII and IX, respectively. Patients with severe hemophilia (< 0.01 IU mL−1) and some patients with moderate hemophilia (0.01–0.05 IU mL−1) administer clotting factor concentrates prophylactically. Desmopressin (d-amino d-arginine vasopressin) can be applied in patients with non-severe hemophilia A. The aim of administration of factor concentrates or desmopressin is the prevention or cessation of bleeding. Despite weight-based dosing, it has been demonstrated that factor concentrates still exhibit considerable pharmacokinetic variability. Population pharmacokinetic analyses, in which this variability is quantified and explained, are increasingly performed in hemophilia research. These analyses can assist in the identification of important patient characteristics and can be applied to perform patient-tailored dosing. This review aims to present and discuss the population pharmacokinetic analyses that have been conducted to develop population pharmacokinetic models describing factor levels after administration of factor VIII or factor IX concentrates or d-amino d-arginine vasopressin. In total, 33 publications were retrieved from the literature. Two approaches were applied to perform population pharmacokinetic analyses, the standard two-stage approach and non-linear mixed-effect modeling. Using the standard two-stage approach, four population pharmacokinetic models were established describing factor VIII levels. In the remaining 29 analyses, the non-linear mixed-effect modeling approach was applied. NONMEM was the preferred software to establish population pharmacokinetic models. In total, 18 population pharmacokinetic analyses were conducted on the basis of data from a single product. From all available population pharmacokinetic analyses, 27 studies also included data from pediatric patients. In the majority of the population pharmacokinetic models, the population pharmacokinetic parameters were allometrically scaled using actual body weight. In this review, the available methods used for constructing the models, key features of these models, patient population characteristics, and established covariate relationships are described in detail.
Collapse
Affiliation(s)
- Tim Preijers
- Hospital Pharmacy-Clinical Pharmacology, Academic University Medical Centers, Location AMC, Amsterdam, The Netherlands
| | - Lisette M Schütte
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Marieke J H A Kruip
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Marjon H Cnossen
- Department of Pediatric Hematology, Sophia Children's Hospital, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Frank W G Leebeek
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Reinier M van Hest
- Hospital Pharmacy-Clinical Pharmacology, Academic University Medical Centers, Location AMC, Amsterdam, The Netherlands
| | - Ron A A Mathôt
- Hospital Pharmacy-Clinical Pharmacology, Academic University Medical Centers, Location AMC, Amsterdam, The Netherlands. .,Hospital Pharmacy-Clinical Pharmacology, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Meibergdreef 9, P.O. Box 22660, 1100 DD, Amsterdam, The Netherlands.
| |
Collapse
|
16
|
Rayment R, Chalmers E, Forsyth K, Gooding R, Kelly AM, Shapiro S, Talks K, Tunstall O, Biss T. Guidelines on the use of prophylactic factor replacement for children and adults with Haemophilia A and B. Br J Haematol 2020; 190:684-695. [PMID: 32390158 DOI: 10.1111/bjh.16704] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/04/2020] [Accepted: 04/08/2020] [Indexed: 01/19/2023]
Affiliation(s)
| | | | | | | | - Anne M Kelly
- Cambridge University Hospitals NHS foundation Trust, Cambridge, UK
| | - Susan Shapiro
- NIHR Oxford Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Kate Talks
- The Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, UK
| | - Oliver Tunstall
- University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - Tina Biss
- The Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, UK
| | | |
Collapse
|
17
|
Real Life Population Pharmacokinetics Modelling of Eight Factors VIII in Patients with Severe Haemophilia A: Is It Always Relevant to Switch to an Extended Half-Life? Pharmaceutics 2020; 12:pharmaceutics12040380. [PMID: 32326156 PMCID: PMC7238177 DOI: 10.3390/pharmaceutics12040380] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 04/10/2020] [Accepted: 04/17/2020] [Indexed: 01/19/2023] Open
Abstract
We retrospectively analysed the data files of 171 adults and 87 children/adolescents with severe haemophilia, except for 14 patients (moderate; minor) (1), to develop a global population pharmacokinetic (PK) model for eight factors VIII (FVIII) that could estimate individual PK parameters for targeting the desired level of FVIII activity (FVIII:C); and (2) to compare half-life (HL) in patients switching from a standard half-life (SHL) to an extended half-life (EHL) and evaluate the relevance of the switch. One-stage clotting assay for the measurement of FVIII activity (FVIII:C, IU/mL) was used for population PK modelling. The software, Monolix version 2019R1, was used for non-linear mixed-effects modelling. A linear two-compartment model best described FVIII:C. The estimated PK parameters (between-subject variability) were: 2640 mL (23.2%) for volume of central compartment (V1), 339 mL (46.8%) for volume of peripheral compartment (V2), 135 mL/h for Q (fixed random effect), and 204 mL/h (34.9%) for clearance (Cl). Weight, age, and categorical covariate EHL were found to influence Cl and only weight for V1. This model can be used for all of the FVIII cited in the study. Moreover, we demonstrated, in accordance with previous studies, that Elocta had longer half-life (EHL) than SHL (mean ratio: 1.48) as compared to Advate, Factane, Kogenate, Novoeight, and Refacto.
Collapse
|
18
|
Hemophilia A and von Willebrand deficiency: therapeutic implications. Blood Coagul Fibrinolysis 2020; 31:397-401. [PMID: 32255574 DOI: 10.1097/mbc.0000000000000908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
: Hemophilia A is an X-linked bleeding disorder caused by a deficiency of factor VIII. Depending on the factor VIII activity in patient's plasma, we can have three different forms of hemophilia A: mild (5-40 IU/dl), moderate (1-5 IU/dl) and severe (<1 IU/dl). The most common symptoms include recurrent bleeding episodes of soft tissues and joints. The treatment is based on the prophylactic use of clotting factor concentrates to prevent bleeding episodes. We describe three cases of patients with initially diagnosis of hemophilia A that show different clinical severity, undergoing prophylactic therapies with low benefit. In these patients, the dosage of von Willebrand antigen revealed either low level or absence of this factor, which in one case was caused by the occurrence of a type III form of von Willebrand disease.
Collapse
|
19
|
Chowdary P. Extended half-life recombinant products in haemophilia clinical practice - Expectations, opportunities and challenges. Thromb Res 2019; 196:609-617. [PMID: 31883700 DOI: 10.1016/j.thromres.2019.12.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 12/03/2019] [Accepted: 12/18/2019] [Indexed: 02/06/2023]
Abstract
Extended half-life (EHL) products have shown robust efficacy in clinical trials, whilst allowing for less intense treatment regimens when compared with standard half-life products. Regimen optimisation with EHL products could lead to further improvements in bleeding rates, quality of life and reductions in treatment burden. Patients now expect good efficacy, a lower treatment burden and equivalent safety when compared with standard half-life products. As our knowledge base grows these expectations have evolved and targeting an annualised bleeding rate of zero has become a more realistic clinical goal. Personalised prophylaxis can help patients achieve these goals. However, a number of challenges still remain, including cost, challenges in predicting outcomes for patients and differences in patients' and clinicians' expectations. When switching a patient, comprehensive patient care can reduce the impact of these issues. This review presents in brief the protein therapeutics with an extended half-life, including key trial results, challenges of chronic care that impact on patients' outcomes and how the modified proteins might help address some of these issues. In addition, practical steps for managing the switch to EHL products are presented.
Collapse
Affiliation(s)
- Pratima Chowdary
- Katharine Dormandy Haemophilia and Thrombosis Centre, Royal Free Hospital, London, UK.
| |
Collapse
|
20
|
Shah A, Solms A, Wiegmann S, Ahsman M, Berntorp E, Tiede A, Iorio A, Mancuso ME, Zhivkov T, Lissitchkov T. Direct comparison of two extended-half-life recombinant FVIII products: a randomized, crossover pharmacokinetic study in patients with severe hemophilia A. Ann Hematol 2019; 98:2035-2044. [PMID: 31236667 PMCID: PMC6700041 DOI: 10.1007/s00277-019-03747-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/15/2019] [Indexed: 11/25/2022]
Abstract
BAY 94-9027 is an extended-half-life, recombinant factor VIII (rFVIII) product conjugated with a 60-kDa branched polyethylene glycol (PEG) molecule indicated for use in previously treated patients (aged ≥ 12 years) with hemophilia A. This randomized, open-label, two-way crossover study compared the pharmacokinetics (PK) of BAY 94-9027 and rFVIII Fc fusion protein (rFVIIIFc) in patients with hemophilia A. Patients aged 18-65 years with FVIII < 1% and ≥ 150 exposure days to FVIII were randomized to receive intravenous single-dose BAY 94-9027 60 IU/kg followed by rFVIIIFc 60 IU/kg or vice versa, with ≥ 7-day wash-out between doses. FVIII activity was measured by one-stage assay. PK parameters, including area under the curve from time 0 to the last data point (AUClast, primary parameter), half-life, and clearance were calculated. Eighteen patients were randomized and treated. No adverse events were observed. In the analysis set excluding one outlier, geometric mean (coefficient of variation [%CV, 95% confidence interval {CI}]) AUClast was significantly higher for BAY 94-9027 versus rFVIIIFc (2940 [37.8, 2440-3550] IU h/dL versus 2360 [31.8, 2010-2770] IU h/dL, p = 0.0001). A population PK model was developed to simulate time to reach FVIII threshold levels; median time to 1 IU/dL was approximately 13 h longer for BAY 94-9027 versus rFVIIIFc after a single infusion of 60 IU/kg. In conclusion, BAY 94-9027 had a superior PK profile versus rFVIIIFc. ClinicalTrials.gov : NCT03364998.
Collapse
Affiliation(s)
| | | | | | | | - Erik Berntorp
- Centre for Thrombosis and Haemostasis, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Andreas Tiede
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Alfonso Iorio
- Department of Health Research Methods, Evidence and Impact, and Department of Medicine, McMaster University, Hamilton, Canada
| | - Maria Elisa Mancuso
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Milan, Italy
| | | | | |
Collapse
|
21
|
Abrantes JA, Solms A, Garmann D, Nielsen EI, Jönsson S, Karlsson MO. Relationship between factor VIII activity, bleeds and individual characteristics in severe hemophilia A patients. Haematologica 2019; 105:1443-1453. [PMID: 31371418 PMCID: PMC7193498 DOI: 10.3324/haematol.2019.217133] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 07/23/2019] [Indexed: 01/19/2023] Open
Abstract
Pharmacokinetic-based prophylaxis of replacement factor VIII (FVIII) products has been encouraged in recent years, but the relationship between exposure (factor VIII activity) and response (bleeding frequency) remains unclear. The aim of this study was to characterize the relationship between FVIII dose, plasma FVIII activity, and bleeding patterns and individual characteristics in severe hemophilia A patients. Pooled pharmacokinetic and bleeding data during prophylactic treatment with BAY 81-8973 (octocog alfa) were obtained from the three LEOPOLD trials. The population pharmacokinetics of FVIII activity and longitudinal bleeding frequency, as well as bleeding severity, were described using non-linear mixed effects modeling in NONMEM. In total, 183 patients [median age 22 years (range, 1-61); weight 60 kg (11-124)] contributed with 1,535 plasma FVIII activity observations, 633 bleeds and 11 patient/study characteristics [median observation period 12 months (3.1-13.1)]. A parametric repeated time-to-categorical bleed model, guided by plasma FVIII activity from a 2-compartment population pharmacokinetic model, described the time to the occurrence of bleeds and their severity. Bleeding probability decreased with time of study, and a bleed was not found to affect the time of the next bleed. Several covariate effects were identified, including the bleeding history in the 12-month pre-study period increasing the bleeding hazard. However, unexplained inter-patient variability in the phenotypic bleeding pattern remained large (111%CV). Further studies to translate the model into a tool for dose individualization that considers the individual bleeding risk are required. Research was based on a post-hoc analysis of the LEOPOLD studies registered at clinicaltrials.gov identifiers: 01029340, 01233258 and 01311648.
Collapse
Affiliation(s)
- João A Abrantes
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | | | | | - Elisabet I Nielsen
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Siv Jönsson
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Mats O Karlsson
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| |
Collapse
|
22
|
Carcao MD, Chelle P, Clarke E, Kim L, Tiseo L, Morfini M, Hossain T, Rand ML, Brown C, Edginton AN, Lillicrap D, Iorio A, Blanchette VS. Comparative pharmacokinetics of two extended half-life FVIII concentrates (Eloctate and Adynovate) in adolescents with hemophilia A: Is there a difference? J Thromb Haemost 2019; 17:1085-1096. [PMID: 31038793 DOI: 10.1111/jth.14469] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 04/09/2019] [Accepted: 04/19/2019] [Indexed: 01/19/2023]
Abstract
Essentials The PK parameters of Eloctate vs Adynovate were compared using one-stage and chromogenic assays in 25 boys (12-18 years). The FVIII levels were taken at 3, 24, 48, and 72 hours following a dose of either FVIII; levels analyzed by WAPPS PK program. The PK profiles (half-life, clearance, and time to 5%, 3%, and 1%) were not statistically different for the two EHL FVIIIs. The significant interpatient variability in PK is mainly related to VWF levels (and blood group). BACKGROUND A head-to-head comparison of the pharmokinetcs (PK) of extended half-life (EHL) factor VIII (FVIII) concentrates in the same subjects has not been reported. Recently, boys (ages 12-18 years) with hemophilia A in Canada were required to switch from Eloctate to Adynovate. OBJECTIVES Compare the PK profiles of Eloctate vs Adynovate in the same boys. METHODS Boys switching from Eloctate to Adynovate prophylaxis had FVIII levels sampled at 3, 24, 48, and 72 hours following a regular prophylactic infusion of Eloctate and then 1-3 months later, of Adynovate. Testing was done by one-stage assay (OSA) and chromogenic assay (CA). The PK parameters were determined with the Web Accessible Population Pharmacokinetic Service (WAPPS)-Hemo PK tool. RESULTS Twenty-five boys (mean age 15.3 years; range: 12.1-18.4; 9 O blood group) underwent switching. Mean (range) terminal half-lives with the OSA were 16.1 hours (10.4 to 23.4; Eloctate) and 16.7 hours (11.0 to 23.6; Adynovate) (NS). With the CA, these were 18.0 hours (12.0 to 25.5; Eloctate) and 16.0 hours (10.3 to 22.9; Adynovate) (P = 0.001). There were no significant differences between the two EHL-FVIIIs in clearance, area under the concentration vs time curve (AUC), Vss, or time for FVIII levels to drop to 5%, 3%, and 1%. At the 72-h time point, mean observed FVIII levels following a mean dose of 39.3 IU/kg of Eloctate were 4.4% (OSA) and 4.4% (CA). For Adynovate, these were 5.1% (OSA) and 5.3% (CA) following similar doses. There was considerable interpatient variation in PK, mainly explained by differences in blood group/von Willebrand factor (VWF) levels. CONCLUSIONS Eloctate and Adynovate have almost identical PK parameters. When switching from one to another no prophylaxis regimen change is needed.
Collapse
Affiliation(s)
- Manuel D Carcao
- Division of Haematology/Oncology, Department of Paediatrics and Child Health Evaluative Sciences, Research Institute, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Pierre Chelle
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada
| | - Emily Clarke
- Department of Nursing, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Lussia Kim
- Child Health Evaluative Sciences, Research Institute, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Laura Tiseo
- Child Health Evaluative Sciences, Research Institute, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | | | - Taneya Hossain
- Translational Medicine, Research Institute, Hospital for Sick Children, Toronto, ON, Canada
| | - Margaret L Rand
- Division of Haematology/Oncology, Department of Paediatrics and Translational Medicine, Research Institute, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
- Departments of Laboratory Medicine & Pathobiology and Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Christine Brown
- Department of Pathology & Molecular Medicine, Queen's University, Kingston, ON, Canada
| | | | - David Lillicrap
- Department of Pathology & Molecular Medicine, Queen's University, Kingston, ON, Canada
| | - Alfonso Iorio
- McMaster-Bayer Endowed Research Chair for Clinical Epidemiology of Congenital Bleeding Disorders, Department of Medicine, McMaster University, Hamilton, ON, Canada
- Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, ON, Canada
| | - Victor S Blanchette
- Division of Haematology/Oncology, Department of Paediatrics and Child Health Evaluative Sciences, Research Institute, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
23
|
Chelle P, Yeung CHT, Bonanad S, Morales Muñoz JC, Ozelo MC, Megías Vericat JE, Iorio A, Spears J, Mir R, Edginton A. Routine clinical care data for population pharmacokinetic modeling: the case for Fanhdi/Alphanate in hemophilia A patients. J Pharmacokinet Pharmacodyn 2019; 46:427-438. [PMID: 31115857 PMCID: PMC6820598 DOI: 10.1007/s10928-019-09637-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Accepted: 04/11/2019] [Indexed: 12/15/2022]
Abstract
Fanhdi/Alphanate is a plasma derived factor VIII concentrate used for treating hemophilia A, for which there has not been any dedicated model describing its pharmacokinetics (PK). A population PK model was developed using data extracted from the Web-Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo) project. WAPPS-Hemo provided individual PK profiles for hemophilia patients using sparse observations as provided in routine clinical care by hemophilia centers. Plasma factor activity measurements and covariate data from hemophilia A patients on Fanhdi/Alphanate were extracted from the WAPPS-Hemo database. A population PK model was developed using NONMEM and evaluated for suitability for Bayesian forecasting using prediction-corrected visual predictive check (pcVPC), cross validation, limited sampling analysis and external evaluation against a population PK model developed on rich sampling data. Plasma factor activity measurements from 92 patients from 12 centers were used to derive the model. The PK was best described by a 2-compartment model including between subject variability on clearance and central volume, fat free mass as a covariate on clearance, central and peripheral volumes, and age as covariate on clearance. Evaluations showed that the developed population PK model could predict the PK parameters of new individuals based on limited sampling analysis and cross and external evaluations with acceptable precision and bias. This study shows the feasibility of using real-world data for the development of a population PK model. Evaluation and comparison of the model for Bayesian forecasting resulted in similar results as a model developed using rich sampling data.
Collapse
Affiliation(s)
- Pierre Chelle
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada
| | - Cindy H T Yeung
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada
| | | | | | - Margareth C Ozelo
- Unidade de Hemofilia IHTC 'Claudio L. P. Correa', Instituto Nacional de Tecnologia do Sangue, Hemocentro UNICAMP, University of Campinas, Campinas, Brazil
| | | | - Alfonso Iorio
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada
- Department of Medicine, McMaster University, Hamilton, ON, Canada
| | | | | | - Andrea Edginton
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada.
| |
Collapse
|
24
|
McEneny-King A, Chelle P, Foster G, Keepanasseril A, Iorio A, Edginton AN. Development and evaluation of a generic population pharmacokinetic model for standard half-life factor VIII for use in dose individualization. J Pharmacokinet Pharmacodyn 2019; 46:411-426. [DOI: 10.1007/s10928-019-09634-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 04/09/2019] [Indexed: 01/19/2023]
|
25
|
Strategies for Individualized Dosing of Clotting Factor Concentrates and Desmopressin in Hemophilia A and B. Ther Drug Monit 2019; 41:192-212. [DOI: 10.1097/ftd.0000000000000625] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
26
|
Delavenne X, Dargaud Y, Ollier E, Négrier C. Dose tailoring of human cell line-derived recombinant factor VIII simoctocog alfa: Using a limited sampling strategy in patients with severe haemophilia A. Br J Clin Pharmacol 2019; 85:771-781. [PMID: 30633808 PMCID: PMC6422655 DOI: 10.1111/bcp.13858] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 12/19/2018] [Accepted: 12/24/2018] [Indexed: 01/19/2023] Open
Abstract
AIMS The use of factor VIII (FVIII) prophylaxis in haemophilia A is considered the standard of care, particularly in children. Despite adjustment of doses for body weight and/or age, a large pharmacokinetic (PK) variability between patients has been observed. PK-tailored prophylaxis may help clinicians adjust coagulation factor FVIII activity (FVIII:C) to the desired level, which may differ in individual patients. The objective was to develop a population PK model for simoctocog alfa based on pooled clinical trial data and to develop a Bayesian estimator to allow PK parameters in individual patients to be estimated using a reduced number of blood samples. METHODS PK data from 86 adults and 29 children/adolescents with severe haemophilia A were analysed. The FVIII data measured using 2 different assays (chromogenic and the 1-stage clotting assay) were fit to separate develop population PK models using nonlinear mixed-effect models. A Bayesian estimator was then developed to estimate the time above the threshold of 1%. RESULTS The PK data for chromogenic and the 1-stage clotting assays were both best described by a 2-compartment models. Simulations demonstrated good predictive capacity. The limited sampling strategy using blood sample at 3 and 24 hours allowed an accurate estimation of the time above the threshold of 1% FVIII:C (mean bias 0.01 and 0.11, mean precision 0.18 and 0.45 for 2 assay methods). CONCLUSION In this study, we demonstrated that a Bayesian approach can help to reduce the number of samples required to estimate the time above the threshold of 1% FVIII:C with good accuracy.
Collapse
Affiliation(s)
- Xavier Delavenne
- INSERM, UMR 1059, Dysfonction Vasculaire et de l'HémostaseUniversité de LyonSaint EtienneFrance
| | - Yesim Dargaud
- Unité d'Hémostase Clinique, Hôpital Cardiologique Louis PradelUniversité Lyon 1LyonFrance
| | - Edouard Ollier
- INSERM, UMR 1059, Dysfonction Vasculaire et de l'HémostaseUniversité de LyonSaint EtienneFrance
| | - Claude Négrier
- Unité d'Hémostase Clinique, Hôpital Cardiologique Louis PradelUniversité Lyon 1LyonFrance
| |
Collapse
|
27
|
The effect of unmeasurable endogenous plasma factor activity levels on factor VIII dosing in patients with severe hemophilia A. Thromb Res 2018; 170:53-59. [DOI: 10.1016/j.thromres.2018.08.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 08/01/2018] [Accepted: 08/08/2018] [Indexed: 01/19/2023]
|
28
|
Hecht M, Veigure R, Couchman L, S Barker CI, Standing JF, Takkis K, Evard H, Johnston A, Herodes K, Leito I, Kipper K. Utilization of data below the analytical limit of quantitation in pharmacokinetic analysis and modeling: promoting interdisciplinary debate. Bioanalysis 2018; 10:1229-1248. [PMID: 30033744 DOI: 10.4155/bio-2018-0078] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Traditionally, bioanalytical laboratories do not report actual concentrations for samples with results below the LOQ (BLQ) in pharmacokinetic studies. BLQ values are outside the method calibration range established during validation and no data are available to support the reliability of these values. However, ignoring BLQ data can contribute to bias and imprecision in model-based pharmacokinetic analyses. From this perspective, routine use of BLQ data would be advantageous. We would like to initiate an interdisciplinary debate on this important topic by summarizing the current concepts and use of BLQ data by regulators, pharmacometricians and bioanalysts. Through introducing the limit of detection and evaluating its variability, BLQ data could be released and utilized appropriately for pharmacokinetic research.
Collapse
Affiliation(s)
- Max Hecht
- Chair of Analytical Chemistry, Institute of Chemistry, University of Tartu, 14a Ravila Street, 50411 Tartu, Estonia
- Analytical Services International, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK
| | - Rūta Veigure
- Chair of Analytical Chemistry, Institute of Chemistry, University of Tartu, 14a Ravila Street, 50411 Tartu, Estonia
| | - Lewis Couchman
- Analytical Services International, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK
| | - Charlotte I S Barker
- Paediatric Infectious Diseases Research Group, Institute for Infection & Immunity, St George's University of London, London, SW17 0RE, UK
- Inflammation, Infection & Rheumatology Section, UCL Great Ormond Street Institute of Child Health, London, WC1N 1EH, UK
- Paediatric Infectious Diseases Unit, St George's University Hospitals NHS Foundation Trust, London, SW17 0RE, UK
| | - Joseph F Standing
- Paediatric Infectious Diseases Research Group, Institute for Infection & Immunity, St George's University of London, London, SW17 0RE, UK
- Inflammation, Infection & Rheumatology Section, UCL Great Ormond Street Institute of Child Health, London, WC1N 1EH, UK
| | - Kalev Takkis
- Analytical Services International, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK
| | - Hanno Evard
- Chair of Analytical Chemistry, Institute of Chemistry, University of Tartu, 14a Ravila Street, 50411 Tartu, Estonia
| | - Atholl Johnston
- Analytical Services International, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK
- Clinical Pharmacology, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Koit Herodes
- Chair of Analytical Chemistry, Institute of Chemistry, University of Tartu, 14a Ravila Street, 50411 Tartu, Estonia
| | - Ivo Leito
- Chair of Analytical Chemistry, Institute of Chemistry, University of Tartu, 14a Ravila Street, 50411 Tartu, Estonia
| | - Karin Kipper
- Chair of Analytical Chemistry, Institute of Chemistry, University of Tartu, 14a Ravila Street, 50411 Tartu, Estonia
- Analytical Services International, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK
| |
Collapse
|
29
|
Iorio A, Edginton AN, Blanchette V, Blatny J, Boban A, Cnossen M, Collins P, Croteau SE, Fischer K, Hart DP, Ito S, Korth‐Bradley J, Lethagen S, Lillicrap D, Makris M, Mathôt R, Morfini M, Neufeld EJ, Spears J. Performing and interpreting individual pharmacokinetic profiles in patients with Hemophilia A or B: Rationale and general considerations. Res Pract Thromb Haemost 2018; 2:535-548. [PMID: 30046759 PMCID: PMC6046594 DOI: 10.1002/rth2.12106] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 04/09/2018] [Indexed: 01/19/2023] Open
Abstract
OBJECTIVES In a separate document, we have provided specific guidance on performing individual pharmacokinetic (PK) studies using limited samples in persons with hemophilia with the goal to optimize prophylaxis with clotting factor concentrates. This paper, intended for clinicians, aims to describe how to interpret and apply PK properties obtained in persons with hemophilia. METHODS The members of the Working Party on population PK (PopPK) of the ISTH SSC Subcommittee on Factor VIII and IX and rare bleeding disorders, together with additional hemophilia and PK experts, completed a survey and ranking exercise whereby key areas of interest in the field were identified. The group had regular web conferences to refine the manuscript's scope and structure, taking into account comments from the external feedback to the earlier document. RESULTS Many clinical decisions in hemophilia are based on some form of explicit or implicit PK assessment. Individual patient PK profiles can be analyzed through traditional or PopPK methods, with the latter providing the advantage of fewer samples needing to be collected on any prophylaxis regimen, and without the need the for a washout period. The most useful presentation of PK results for clinical decision making are a curve of the factor activity level over time, the time to achieve a certain activity level, or related parameters like half-life or exposure (AUC). Software platforms have been developed to deliver this information to clinicians at the point of care. Key characteristics of studies measuring average PK parameters were reviewed, outlining what makes a credible head-to-head comparison among different concentrates. Large data collections of PK and treatment outcomes currently ongoing will advance care in the future. CONCLUSIONS Traditionally used to compare different concentrates, PK can support tailoring of hemophilia treatment by individual profiling, which is greatly simplified by adopting a PopPK/Bayesian method and limited sampling protocol.
Collapse
Affiliation(s)
- Alfonso Iorio
- Department of Health Research, Methods, Evidence and ImpactMcMaster UniversityHamiltonONCanada
- Department of MedicineMcMaster UniversityHamiltonONCanada
| | | | - Victor Blanchette
- Division of Hematology/OncologyHospital for Sick Children and Department of PediatricsUniversity of TorontoTorontoONCanada
| | - Jan Blatny
- Department of Paediatric HaematologyUniversity Hospital BrnoBrnoCzech Republic
| | - Ana Boban
- Department of Internal MedicineUniversity Hospital CenterZagrebCroatia
| | - Marjon Cnossen
- Department of Pediatric HematologyErasmus University Medical CenterSophia Children’s HospitalRotterdamThe Netherlands
| | - Peter Collins
- Arthur Bloom Haemophilia CentreSchool of MedicineUniversity Hospital of WalesCardiff UniversityCardiffUK
| | | | - Katheljin Fischer
- Van CreveldkliniekUniversity Medical CenterUtrecht UniversityUtrechtThe Netherlands
| | - Daniel P. Hart
- The Royal London Hospital Haemophilia Centre, Barts and The London School of Medicine and DentistryLondonUK
| | | | | | | | - David Lillicrap
- Department of Pathology & Molecular MedicineQueen’s UniversityKingstonONCanada
| | - Mike Makris
- Department of Infection, Immunity& Cardiovascular DiseaseUniversity of SheffieldSheffieldUK
| | - Ron Mathôt
- Hospital Pharmacy–Clinical PharmacologyAcademic Medical CentreAmsterdamThe Netherlands
| | | | | | | |
Collapse
|
30
|
Hermans C, Mahlangu J, Booth J, Schütz H, Santagostino E, Young G, Lee HY, Steinitz-Trost KN, Blanchette V, Berntorp E. Pharmacokinetic modelling and validation of the half-life extension needed to reduce the burden of infusions compared with standard factor VIII. Haemophilia 2018; 24:376-384. [PMID: 29732708 DOI: 10.1111/hae.13483] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2018] [Indexed: 01/17/2023]
Abstract
INTRODUCTION Currently, no universally accepted definition of extended half-life (EHL) recombinant FVIII (rFVIII) exists. Identifying the minimum half-life extension ratio required for a reduction in dosing frequency compared with standard rFVIII could enable a more practical approach to decisions around prophylaxis with EHL rFVIII. AIM To identify the half-life extension ratio required to decrease rFVIII dosing frequency by at least 1 day while maintaining the proportion of patients with plasma rFVIII levels above 1 IU/dL and without increasing the total weekly dose. METHODS A previously published population pharmacokinetic model for standard rFVIII was used to estimate the percentage of patients with factor VIII (FVIII) levels always >1 IU/dL using various benchmark regimens. Using modelling, dosing frequency was reduced while rFVIII half-life was extended until the percentage of patients with FVIII >1 IU/dL equalled that of the benchmark regimen. RESULTS Benchmark 3×/wk dosing totalling 100 IU/kg/wk of rFVIII resulted in 56.6% of patients with FVIII levels always >1 IU/dL. With 2×/wk dosing, totalling 80 or 90 IU/kg/wk, half-life extensions required to maintain 56.6% of patients at FVIII levels >1 IU/dL were 1.30 and 1.26, respectively. A half-life extension ratio of 1.33 was required to change dosing from every 48 hours to every 72 hours (both at 105 IU/kg/wk) while maintaining 92.8% of patients with FVIII >1 IU/dL. CONCLUSION Based on this investigation, EHL rFVIII products should have a minimum half-life extension ratio of 1.3 to provide a reduction in dosing frequency from 3× to 2×/wk compared with standard rFVIII products while maintaining the same minimum FVIII trough level.
Collapse
Affiliation(s)
- C Hermans
- Haemostasis and Thrombosis Unit, Division of Haematology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - J Mahlangu
- Faculty of Health Sciences, Charlotte Maxeke Johannesburg Academic Hospital, University of the Witwatersrand and National Health Laboratory Service, Johannesburg, South Africa
| | | | | | - E Santagostino
- A. Bianchi Bonomi Hemophilia and Thrombosis Center, IRCCS Ca' Granda Foundation, Maggiore Hospital Policlinico of Milan, Milan, Italy
| | - G Young
- Children's Hospital Los Angeles, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | | | | | - V Blanchette
- Department of Pediatrics, Division of Hematology/Oncology, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - E Berntorp
- Centre for Thrombosis and Haemostasis, Lund University, Malmö, Sweden
| |
Collapse
|
31
|
Herbert RD, Broderick CR, Barnes C, Billot L, Zhou A, Latimer J. Optimization of prophylaxis for hemophilia A. PLoS One 2018; 13:e0192783. [PMID: 29447219 PMCID: PMC5813962 DOI: 10.1371/journal.pone.0192783] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 01/30/2018] [Indexed: 11/18/2022] Open
Abstract
Background & aims Prophylactic injections of factor VIII reduce the incidence of bleeds and slow the development of joint damage in people with hemophilia. The aim of this study was to identify optimal person-specific prophylaxis regimens for children with hemophilia A. Methods Analytic and numerical methods were used to identify prophylaxis regimens which maximize the time for which plasma factor VIII concentrations exceed a threshold, maximize the lowest plasma factor VIII concentrations, and minimize risk of bleeds. Results It was demonstrated analytically that, for any injection schedule, the regimen that maximizes the lowest factor VIII concentration involves sharing doses between injections so that all of the trough concentrations in a prophylaxis cycle are equal. Numerical methods were used to identify optimal prophylaxis schedules and explore the trade-offs between efficacy and acceptability of different prophylaxis regimens. The prophylaxis regimen which minimizes risk of bleeds depends on the person’s pattern of physical activity and may differ greatly from prophylaxis regimens that optimize pharmacokinetic parameters. Prophylaxis regimens which minimize risk of bleeds also differ from prophylaxis regimens that are typically prescribed. Predictions about which regimen is optimal are sensitive to estimates of the effects on risk of bleeds of factor VIII concentration and physical activity. Conclusion The methods described here can be used to identify optimal, person-specific prophylaxis regimens for children with hemophilia A.
Collapse
Affiliation(s)
- Robert D. Herbert
- Neuroscience Research Australia (NeuRA), Randwick, NSW, Australia
- University of New South Wales, Kensington, NSW, Australia
- * E-mail:
| | - Carolyn R. Broderick
- University of New South Wales, Kensington, NSW, Australia
- The Children’s Hospital at Westmead, Westmead, NSW, Australia
| | - Chris Barnes
- The Royal Children’s Hospital, Melbourne, VIC, Australia
| | - Laurent Billot
- University of New South Wales, Kensington, NSW, Australia
- The George Institute for Global Health, Camperdown, NSW, Australia
| | - Albert Zhou
- University of Sydney, Camperdown, NSW, Australia
| | - Jane Latimer
- University of Sydney, Camperdown, NSW, Australia
| |
Collapse
|
32
|
Iorio A. Using pharmacokinetics to individualize hemophilia therapy. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2017; 2017:595-604. [PMID: 29222309 PMCID: PMC6142544 DOI: 10.1182/asheducation-2017.1.595] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Prevention and treatment of bleeding in hemophilia requires that plasma clotting factor activity of the replaced factor exceeds a defined target level. Most clinical decisions in hemophilia are based on implicit or explicit application of pharmacokinetic measures. The large interindividual variability in pharmacokinetics of factor concentrates suggests that relying on the average pharmacokinetic characteristics of factor concentrates would not allow optimizing the treatment of individual patients; for example, adjusting the frequency of infusions and targeting a specific clotting factor activity level on a case-by-case basis. However, individual pharmacokinetic profiles are seldom assessed as part of routine clinical care. Population pharmacokinetics provide options for precise and convenient characterization of pharmacokinetics characteristics of factor concentrates, simplified individual pharmacokinetic profiling, and individualized dosing. Population pharmacokinetics allow for the incorporation of determinants of interpatient variability and reduces the need for extensive postinfusion plasma sampling. Barriers to the implementation of population pharmacokinetics are the need for concentrate-specific pharmacokinetic models, Bayesian calculation power, and specific expertise for production, validation, and appraisal of forecasted estimates. Population pharmacokinetics provide an important theoretical and practical contribution to tailoring the treatment of hemophilia. The need remains for prospective exploration of the clinical impact of tailoring hemophilia treatment based on individual pharmacokinetics, and for the systematic validation of existing software solutions and concentrate-specific models.
Collapse
Affiliation(s)
- Alfonso Iorio
- Department of Health Research, Methods, Evidence, and Impact, and
- Department of Medicine, McMaster University, Hamilton, ON, Canada
| |
Collapse
|
33
|
Iorio A, Blanchette V, Blatny J, Collins P, Fischer K, Neufeld E. Estimating and interpreting the pharmacokinetic profiles of individual patients with hemophilia A or B using a population pharmacokinetic approach: communication from the SSC of the ISTH. J Thromb Haemost 2017; 15:2461-2465. [PMID: 29119666 DOI: 10.1111/jth.13867] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Indexed: 01/19/2023]
Affiliation(s)
- A Iorio
- Department of Health Research, Methods, Evidence and Impact, McMaster University, Hamilton, Ontario, Canada
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - V Blanchette
- Division of Hematology/Oncology, Hospital for Sick Children and Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada
| | - J Blatny
- Department of Pediatric Hematology, University Hospital Brno, Brno, Czech Republic
| | - P Collins
- Arthur Bloom Haemophilia Centre, School of Medicine, University Hospital of Wales, Cardiff University, Cardiff, UK
| | - K Fischer
- Van Creveldkliniek, University Medical Center, Utrecht, the Netherlands
| | - E Neufeld
- St Jude Children's Research Hospital, Memphis, TN, USA
| |
Collapse
|
34
|
Berntorp E. If you know you will also see: population pharmacokinetics is the way to personalize and optimize prophylaxis in hemophilia. J Thromb Haemost 2017; 15:1103-1105. [PMID: 28339167 DOI: 10.1111/jth.13682] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Indexed: 02/06/2023]
Affiliation(s)
- E Berntorp
- Department of Translational Medicine, Lund University, Malmö Center for Thrombosis and Hemostasis, Malmö, Sweden
| |
Collapse
|
35
|
Leksa N, Chiu PL, Bou-Assaf G, Quan C, Liu Z, Goodman A, Chambers M, Tsutakawa S, Hammel M, Peters R, Walz T, Kulman J. The structural basis for the functional comparability of factor VIII and the long-acting variant recombinant factor VIII Fc fusion protein. J Thromb Haemost 2017; 15:1167-1179. [PMID: 28397397 PMCID: PMC5500164 DOI: 10.1111/jth.13700] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Indexed: 01/13/2023]
Abstract
Essentials Recombinant factor VIII (rFVIII) Fc fusion protein has a 1.5-fold longer half-life than rFVIII. Five orthogonal methods were used to characterize the structure of rFVIIIFc compared to rFVIII. The C-terminal Fc fusion does not perturb the structure of FVIII in rFVIIIFc. The FVIII and Fc components of rFVIIIFc are flexibly tethered and functionally independent. SUMMARY Background Fusion of the human IgG1 Fc domain to the C-terminal C2 domain of B-domain-deleted (BDD) factor VIII (FVIII) results in the recombinant FVIII Fc (rFVIIIFc) fusion protein, which has a 1.5-fold longer half-life in humans. Objective To assess the structural properties of rFVIIIFc by comparing its constituent FVIII and Fc elements with their respective isolated components, and evaluating their structural independence within rFVIIIFc. Methods rFVIIIFc and its isolated FVIII and Fc components were compared by the use of hydrogen-deuterium exchange mass spectrometry (HDX-MS). The structure of rFVIIIFc was also evaluated by the use of X-ray crystallography, small-angle X-ray scattering (SAXS), and electron microscopy (EM). The degree of steric interference by the appended Fc domain was assessed by EM and surface plasmon resonance (SPR). Results HDX-MS analysis of rFVIIIFc revealed that fusion caused no structural perturbations in FVIII or Fc. The rFVIIIFc crystal structure showed that the FVIII component is indistinguishable from published BDD FVIII structures. The Fc domain was not observed, indicating high mobility. SAXS analysis was consistent with an ensemble of rigid-body models in which the Fc domain exists in a largely extended orientation relative to FVIII. Binding of Fab fragments of anti-C2 domain antibodies to BDD FVIII was visualized by EM, and the affinities of the corresponding intact antibodies for BDD FVIII and rFVIIIFc were comparable by SPR analysis. Conclusions The FVIII and Fc components of rFVIIIFc are structurally indistinguishable from their isolated constituents, and show a high degree of structural independence, consistent with the functional comparability of rFVIIIFc and unmodified FVIII.
Collapse
Affiliation(s)
| | - P.-L. Chiu
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | | | | | - Z. Liu
- Biogen, Cambridge, MA, USA
| | | | - M.G. Chambers
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - S.E. Tsutakawa
- Molecular Biophysics & Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - M. Hammel
- Molecular Biophysics & Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | | | - T. Walz
- Biogen, Cambridge, MA, USA
- Laboratory of Molecular Electron Microscopy, Rockefeller University, New York, NY, USA
| | | |
Collapse
|
36
|
Pharmacokinetics, Safety, and Efficacy of Recombinant Factor VIII Fc Fusion Protein: A Practical Review. JOURNAL OF INFUSION NURSING 2017; 40:65-75. [PMID: 28030484 DOI: 10.1097/nan.0000000000000205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Prophylaxis for hemophilia A with conventional factor VIII (FVIII) products requires frequent intravenous dosing, which may reduce adherence. Recombinant factor VIII Fc fusion protein (rFVIIIFc) has a prolonged half-life compared with conventional rFVIII, and has demonstrated safety and efficacy for the prevention and treatment of bleeding episodes in phase 3 studies of patients with severe hemophilia A. Most subjects experienced reduced prophylactic dosing frequency with rFVIIIFc compared with prestudy FVIII; the median total weekly prophylactic consumption was comparable. No subjects developed inhibitors. These results suggest that prophylaxis with rFVIIIFc in patients with hemophilia A may allow less frequent prophylactic dosing while maintaining efficacy, with comparable prophylactic consumption.
Collapse
|
37
|
Garmann D, McLeay S, Shah A, Vis P, Maas Enriquez M, Ploeger BA. Population pharmacokinetic characterization of BAY 81-8973, a full-length recombinant factor VIII: lessons learned - importance of including samples with factor VIII levels below the quantitation limit. Haemophilia 2017; 23:528-537. [PMID: 28220555 DOI: 10.1111/hae.13192] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/27/2016] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The pharmacokinetics (PK), safety and efficacy of BAY 81-8973, a full-length, unmodified, recombinant human factor VIII (FVIII), were evaluated in the LEOPOLD trials. AIM The aim of this study was to develop a population PK model based on pooled data from the LEOPOLD trials and to investigate the importance of including samples with FVIII levels below the limit of quantitation (BLQ) to estimate half-life. METHODS The analysis included 1535 PK observations (measured by the chromogenic assay) from 183 male patients with haemophilia A aged 1-61 years from the 3 LEOPOLD trials. The limit of quantitation was 1.5 IU dL-1 for the majority of samples. Population PK models that included or excluded BLQ samples were used for FVIII half-life estimations, and simulations were performed using both estimates to explore the influence on the time below a determined FVIII threshold. RESULTS In the data set used, approximately 16.5% of samples were BLQ, which is not uncommon for FVIII PK data sets. The structural model to describe the PK of BAY 81-8973 was a two-compartment model similar to that seen for other FVIII products. If BLQ samples were excluded from the model, FVIII half-life estimations were longer compared with a model that included BLQ samples. CONCLUSIONS It is essential to assess the importance of BLQ samples when performing population PK estimates of half-life for any FVIII product. Exclusion of BLQ data from half-life estimations based on population PK models may result in an overestimation of half-life and underestimation of time under a predetermined FVIII threshold, resulting in potential underdosing of patients.
Collapse
Affiliation(s)
| | - S McLeay
- Model Answers Pty Ltd, Brisbane, Qld, Australia
| | | | - P Vis
- LAP&P Consultants BV, Leiden, The Netherlands
| | | | | |
Collapse
|
38
|
Shapiro AD, Mahlangu JN, Perry D, Pasi J, Quon DV, Chowdary P, Tsao E, Li S, Innes A, Pierce GF, Allen GA. Treatment of bleeding episodes with recombinant factor VIII Fc fusion protein in A-LONG study subjects with severe haemophilia A. Haemophilia 2017; 23:392-399. [PMID: 28220631 DOI: 10.1111/hae.13144] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2016] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The Phase 3 A-LONG study demonstrated the safety and efficacy of rFVIIIFc for the control and prevention of bleeding episodes in severe haemophilia A. AIM To describe the treatment of bleeding episodes with rFVIIIFc in the A-LONG study. METHODS A-LONG subjects (<1 IU dL-1 endogenous FVIII) were treated with individualized prophylaxis (Arm 1), weekly prophylaxis (Arm 2) or episodic treatment (Arm 3). Information recorded for each bleeding episode included type, location and dose to treat the episode. RESULTS During A-LONG, 757 bleeding episodes occurred during the efficacy period; the majority [456 (60%)] occurred in Arm 3 (episodic treatment). Of 93 subjects in the prophylaxis arms who entered the study with target joints, 43 (60%) in Arm 1 and 11 (52%) in Arm 2 did not experience a target joint bleed. Overall, 98% of bleeding episodes (and 98% of bleeds involving a target joint) resolved with one or two infusions; the median dose per infusion to treat a bleed was 27 IU kg-1 (27 IU kg-1 for target joints). Using population pharmacokinetic simulations, FVIII activity levels were predicted to be below the upper limit of normal (150 IU dL-1 ) in most patients in the event that rFVIIIFc is used to treat a bleeding episode in close proximity to a prophylactic dose. CONCLUSIONS These findings demonstrate the efficacy of rFVIIIFc for the treatment of acute bleeding episodes in subjects with severe haemophilia A, regardless of treatment regimen.
Collapse
Affiliation(s)
- A D Shapiro
- Indiana Hemophilia and Thrombosis Center, Indianapolis, IN, USA
| | - J N Mahlangu
- Faculty of Health Sciences, University of the Witwatersrand and NHLS Hospital, Parktown, Johannesburg, South Africa
| | - D Perry
- Addenbrookes Hospital, Cambridge, UK
| | - J Pasi
- Barts and The London Comprehensive Care Center, London, UK
| | - D V Quon
- Orthopaedic Hemophilia Treatment Center, Los Angeles, CA, USA
| | - P Chowdary
- Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Royal Free Hospital, London, UK
| | - E Tsao
- Biogen, Cambridge, MA, USA
| | - S Li
- Biogen, Cambridge, MA, USA
| | | | | | | |
Collapse
|
39
|
Chowdary P, Fosbury E, Riddell A, Mathias M. Therapeutic and routine prophylactic properties of rFactor VIII Fc (efraloctocog alfa, Eloctate ®) in hemophilia A. J Blood Med 2016; 7:187-198. [PMID: 27695377 PMCID: PMC5028163 DOI: 10.2147/jbm.s80814] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
rFVIIIFc (efraloctocog alfa, Eloctate®) is an extended half-life (EHL) factor VIII licensed for use in patients with hemophilia A for prophylaxis and treatment of bleeding and surgical episodes. Pharmacokinetic studies in adults have shown a mean 1.5-fold increase in half-life compared to full-length factor VIII. When compared to adults, the half-life is decreased by 8% in adolescents between 12 and 17 years, by 18% in children 6 to <12 years, and by 33% in children between the ages of 2 and <6 years. There is a considerable interindividual variation in the prolongation of the half-life particularly in children and across the age groups, the range extending from no increase to a 2.5-fold increase. In addition to age, von willebrand factor (VWF) antigen level has demonstrated a significant impact on rFVIIIFc half-life, with higher VWF levels associated with greater prolongation of half-life. The pivotal and pediatric clinical trials have demonstrated the efficacy and safety of rFVIIIFc for use in regular prophylaxis and in management of bleeds and surgery. In these studies, just under half the participants showed a zero annualized bleed rate (ABR), and the median ABR (1.6 in the pivotal study for the individualized prophylaxis arm) showed a further decrease in the extension study. On average, the patients required fewer infusions (reduced by at least a third), and the mean weekly consumption seems to be in keeping with standard recombinant factor VIII. EHL rFVIIIFc has made decreased infusion frequency a possibility. However, the interindividual variability in dose and infusion frequency highlights the need for a personalized approach based on individual patient’s half-life and/or response to treatment.
Collapse
Affiliation(s)
- Pratima Chowdary
- Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Royal Free Hospital, London, UK
| | - Emma Fosbury
- Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Royal Free Hospital, London, UK
| | - Anne Riddell
- Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Royal Free Hospital, London, UK
| | - Mary Mathias
- Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Royal Free Hospital, London, UK; Haemophilia Centre, Great Ormond Street Hospital for Children, London, UK
| |
Collapse
|
40
|
Berntorp E, Negrier C, Gozzi P, Blaas P, Lethagen S. Dosing regimens,
FVIII
levels and estimated haemostatic protection with special focus on
rFVIIIF
c. Haemophilia 2016; 22:389-96. [DOI: 10.1111/hae.12887] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/27/2015] [Indexed: 01/03/2023]
Affiliation(s)
- E. Berntorp
- Departments of Hematology and Coagulation Disorders Lund University Skåne University Hospital Malmö Sweden
| | - C. Negrier
- Hematology Division Hemophilia Comprehensive Care Center Hopital Louis Pradel Université Lyon 1 Bron France
| | - P. Gozzi
- Swedish Orphan Biovitrum AB Stockholm Sweden
| | - P‐M. Blaas
- Swedish Orphan Biovitrum AB Stockholm Sweden
| | - S. Lethagen
- Swedish Orphan Biovitrum AB Stockholm Sweden
- University of Copenhagen Copenhagen Denmark
| |
Collapse
|
41
|
Shapiro AD, Li S. Response to Gringeri et al.: 'Recombinant full-length factor VIII (FVIII) and extended half-life FVIII products in prophylaxis--new insight provided by pharmacokinetic modelling'. Haemophilia 2015; 21:e489-92. [PMID: 26173031 DOI: 10.1111/hae.12754] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2015] [Indexed: 11/28/2022]
Affiliation(s)
- A D Shapiro
- Department of Hematology, Indiana Hemophilia and Thrombosis Center, Indianapolis, IN, USA
| | - S Li
- Biogen, Cambridge, MA, USA
| |
Collapse
|