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Mohsenian S, Mannucci PM, Menegatti M, Peyvandi F. Rare inherited coagulation disorders: no longer orphan and neglected. Res Pract Thromb Haemost 2024; 8:102460. [PMID: 39022653 PMCID: PMC11253144 DOI: 10.1016/j.rpth.2024.102460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 05/03/2024] [Accepted: 05/18/2024] [Indexed: 07/20/2024] Open
Abstract
Rare inherited coagulation disorders due to the deficiency or dysfunction of coagulation factors have until recently received less clinical attention than hemophilias and von Willebrand disease. This situation has changed in the last decades, mainly due to therapeutic progress with the availability of more and safer products for replacement therapy produced by plasma fractionation or recombinant DNA technology. This narrative review, based on the latest literature and expert opinion, emphasizes the progress achieved for each of the rare deficiencies, mentions the still unmet therapeutic needs, and sketches the perspectives for further progress.
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Affiliation(s)
- Samin Mohsenian
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Pier Mannuccio Mannucci
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Milan, Italy
| | - Marzia Menegatti
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Milan, Italy
| | - Flora Peyvandi
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Milan, Italy
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2
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Zhu R, Zhao R. The Tip of the Iceberg: Coagulopathy in Pediatric Patients Undergoing Surgery for Epilepsy. World Neurosurg 2024; 181:186-187. [PMID: 37833160 DOI: 10.1016/j.wneu.2023.09.057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2023]
Affiliation(s)
- Renqing Zhu
- Department of Neurosurgery, Children's Hospital of Fudan University, Shanghai, China
| | - Rui Zhao
- Department of Neurosurgery, Children's Hospital of Shanghai, Shanghai, China; Department of Neurosurgery, Hainan Women and Children's Medical Center, Haikou, China
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Stéphan F, Gutermann L, Bourget S, Djabarouti S, Berdugo J, Fardini Y, Clerson P, Hébert G, Belmokhtar C. Real-World Experience with a Human Fibrinogen Concentrate: Clinical Data from Adult and Pediatric Patients Requiring Fibrinogen for Bleeding Control and Prevention. J Clin Pharmacol 2023; 63:1186-1196. [PMID: 37293880 DOI: 10.1002/jcph.2291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 06/01/2023] [Indexed: 06/10/2023]
Abstract
Human fibrinogen concentrate (Fibryga) received temporary approval for fibrinogen replacement therapy in France (2017), with subsequent full approval for congenital and acquired hypofibrinogenemia. We evaluated real-world use for on-demand treatment of bleeding and prophylaxis to enhance our knowledge on fibrinogen concentrate as an option for fibrinogen replacement. Data were retrospectively collected from adult and pediatric patients with fibrinogen deficiency. The primary end point was indication for fibrinogen concentrate use; the secondary end point was treatment success for on-demand treatment/perioperative prophylaxis. The study included 150 adult (median age, 62 years; range, 18-94 years) and 50 pediatric (median age, 3 years; range, 0.01-17 years) patients with acquired fibrinogen deficiency. Fibrinogen concentrate was administered to 47.3% for nonsurgical bleeding, 22.7% for surgical bleeding, and 30.0% for perioperative prophylaxis in adult patients, and to 4.0% for surgical bleeding and 96.0% for perioperative prophylaxis in pediatric patients. Cardiac surgeries accounted for 79.5%/75.0% perioperative prophylaxis and 82.4%/100.0% surgical bleeding cases in adult/pediatric patients, respectively. The mean ± standard deviation (SD, median) total fibrinogen doses were 3.06 ± 1.69 g (32.61 mg/kg), 2.09 ± 1.36 g (22.99 mg/kg), and 2.36 ± 1.25 g (29.67 mg/kg) for adult nonsurgical bleeding, surgical bleeding, and perioperative prophylaxis, respectively; doses of 0.75 ± 0.35 g (47.64 mg/kg) and 0.83 ± 0.62 g (55.56 mg/kg) were used for pediatric surgical bleeding and perioperative prophylaxis, respectively. Treatment success was 85.7%/97.1/93.3% in adults and 50.0%/87.5% in pediatrics for nonsurgical bleeding (adults only), surgical bleeding, and perioperative prophylaxis, respectively. Fibrinogen concentrate demonstrated favorable effectiveness and safety across the age groups. This study contributes to evidence supporting fibrinogen concentrate for bleeding control/prevention in real-world clinical practice, particularly for patients with acquired fibrinogen deficiency.
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Affiliation(s)
- Francois Stéphan
- Service de Réanimation Adultes, Hôpital Marie Lannelongue, Groupe Hospitalier Paris Saint Joseph, Le Plessis Robinson, France
| | - Loriane Gutermann
- Service Pharmacie et Stérilisation, Hôpital Marie Lannelongue, Groupe Hospitalier Paris Saint Joseph, Le Plessis Robinson, France
| | | | - Sarah Djabarouti
- Service Pharmacie, Groupe Hospitalier Sud, CHU de Bordeaux, Pessac, France
| | | | | | | | - Guillaume Hébert
- Service Pharmacie et Stérilisation, Hôpital Marie Lannelongue, Groupe Hospitalier Paris Saint Joseph, Le Plessis Robinson, France
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Colom H, Blasi A, Montoro B, Arévalo AG, Cendrós JM, Sabaté A. Population pharmacokinetic modelling of fibrinogen in patients with congenital or acquired-chronic or acute-hypofibrinogenaemia. Br J Clin Pharmacol 2023; 89:2703-2713. [PMID: 37041125 DOI: 10.1111/bcp.15741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 03/17/2023] [Accepted: 03/25/2023] [Indexed: 04/13/2023] Open
Abstract
AIMS Fibrinogen is the key substrate for coagulation. Fibrinogen pharmacokinetics (PK) after single doses of fibrinogen concentrate (FC), using modelling approaches, has only been evaluated in congenital afibrinogenaemic patients. The aims of this study are to characterize the fibrinogen PK in patients with acquired-chronic (cirrhosis) or acute-hypofibrinogenaemia (critical haemorrhage), showing endogenous production. Influencing factors of differences on the fibrinogen PK between subpopulations will be identified. METHODS A total of 428 time-concentration values from 132 patients were recorded. Eighty-two out of 428 values were from 41 cirrhotic patients administered with placebo and 90 out of 428 were from 45 cirrhotic patients that were given FC, 161 out of 428 values were from 14 afibrinogenaemic patients and 95 out of 428 values were from 32 severe acute trauma haemorrhagic patients. A turnover model that accounted for endogenous production and exogenous dose was fitted using NONMEM74. The production rate (Ksyn), distribution volume (V), plasma clearance (CL) and concentration yielding to 50% of maximal fibrinogen production (EC50) were estimated. RESULTS Fibrinogen disposition was described by a one-compartment model with CL and V values of 0.0456 L·h-1 and 4.34 L·70 kg-1 , respectively. Body weight was statistically significant in V. Three different Ksyn values were identified that increased from 0.00439 g·h-1 (afibrinogenaemia), to 0.0768 g·h-1 (cirrhotics) and 0.1160 g·h-1 (acute severe trauma). EC50 was of 0.460 g·L-1 . CONCLUSIONS This model will be key as a support tool for dose calculation to achieve specified target fibrinogen concentrations, in each of the studied populations.
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Affiliation(s)
- Helena Colom
- Department of Pharmacy and Pharmaceutical Technology and Physical-Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
| | - Annabel Blasi
- Department of Anaesthesiology, Hospital Clinic, IDIBAPS, University of Barcelona Health Campus, Barcelona, Spain
| | - Bruno Montoro
- Department of Hospital Pharmacy, Vall d'Hebron University Hospital, Barcelona, Spain
| | | | - Josep Maria Cendrós
- Department of Pharmacy and Pharmaceutical Technology and Physical-Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
| | - Antoni Sabaté
- Department of Anaesthesiology, Hospital Universitari de Bellvitge, IDIBELL, University of Barcelona Health Campus, Barcelona, Spain
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Khayat CD, Navarro-Puerto J, Ross CR, Subramanian K, Kalappanavar NK, Rucker K, Liang W, Mondou E. Pharmacokinetics, efficacy and safety of a novel fibrinogen concentrate in pediatric patients with congenital afibrinogenemia. Blood Coagul Fibrinolysis 2023; 34:61-69. [PMID: 36484281 DOI: 10.1097/mbc.0000000000001182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Congenital afibrinogenemia treatment with plasma-derived fibrinogen concentrates in pediatric patients is limited. This study investigated the pharmacokinetics, surrogate efficacy, and safety of a plasma-derived fibrinogen concentrate (FIB Grifols) in pediatric patients with congenital afibrinogenemia. METHODS Patients aged <18 years old diagnosed with congenital afibrinogenemia were included in this prospective, multinational, phase 1-2, single-arm study. After a single dose of a plasma-derived fibrinogen concentrate (70 mg/kg body weight), pharmacokinetic parameters were determined from plasma fibrinogen activity (Clauss method) and antigen method (ELISA), and calculated by noncompartmental and population pharmacokinetic (popPK) models. Patients were followed up over 14 days. Efficacy variables were the mean change on thromboelastographic variables (maximum clot firmness [MCF], alpha angle [ α ]) and coagulation tests (prothrombin time, activated partial thromboplastin time, and thrombin time) 1 h postinfusion. Safety parameters were assessed. RESULTS Eleven patients with a median (range) age 8.80 (3.7-12.7) years were treated with the plasma-derived fibrinogen concentrate. Using the popPK modeling, fibrinogen activity reached a mean (standard deviation) Cmax of 1.3 (0.225) g/l, half-life ( t1/2 ) of 60.6 (4.48) h and incremental in vivo recovery (IVR) of 1.86 (0.322) (mg/dl)/(mg/kg). Surrogate efficacy was demonstrated by significant increase in MCF (9.23 [3.94] mm; P < 0.001; 95% confidence interval 6.58, 11.87). All coagulation times were significantly shortened after fibrinogen concentrate infusion. Adverse events were mild or moderate in severity, and unrelated to fibrinogen concentrate. CONCLUSIONS In pediatric patients with congenital afibrinogenemia, plasma-derived fibrinogen concentrate revealed a favorable and specific pharmacokinetic profile, demonstrated efficacy in coagulation and was safe and well tolerated.
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Affiliation(s)
- Claudia Djambas Khayat
- Department of pediatrics, Hotel Dieu de France Hospital Beirut, Saint Joseph University, Lebanon
| | | | - Cecil Reuben Ross
- Department Medicine & Hematology, St. John's Medical College Hospital, Bangalore, Karnataka, India
| | | | | | - Karen Rucker
- Grifols Bioscience Research Group, Grifols, Barcelona, Spain
| | - Wei Liang
- Grifols Bioscience Research Group, Grifols, Barcelona, Spain
| | - Elsa Mondou
- Grifols Bioscience Research Group, Grifols, Barcelona, Spain
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Djambas Khayat C, Lohade SD, Zekavat OR, Kruzhkova I, Solomon C, Knaub S, Peyvandi F. Analysis of fibrinogen concentrate pharmacokinetics and dosing for bleeds and surgery in adults, adolescents, and children with congenital afibrinogenaemia and hypofibrinogenaemia. Haemophilia 2022; 28:1022-1032. [PMID: 35925493 PMCID: PMC9804975 DOI: 10.1111/hae.14619] [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: 02/09/2022] [Revised: 06/01/2022] [Accepted: 06/22/2022] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Congenital afibrinogenaemia and hypofibrinogenaemia are rare coagulation disorders where clotting is impaired due to a lack of fibrinogen. Consequent bleeding episodes (BEs) are treated using human fibrinogen concentrate (HFC). AIM This post-hoc analysis compared HFC pharmacokinetics (PK) and dosing between patient age groups and defined the in vivo recovery (IVR) for children with a- and hypofibrinogenaemia. METHODS The analysis used data from the FORMA-01 (Phase 2), FORMA-02 and FORMA-04 (Phase 3) multinational, prospective, open-label studies in patients with a- and hypofibrinogenaemia. HFC PK in adults/adolescents (≥12 years; FORMA-01) and children (<12 years; FORMA-04) was examined. Haemostatic efficacy in BE treatment and perioperative prophylaxis was examined in FORMA-02 and FORMA-04 using an objective 4-point scale, with success defined as excellent/good. RESULTS Median (range) age was 23 years for FORMA-01 (12-53; n = 22), 26.5 years for FORMA-02 (12-54; n = 25), and 6 years for FORMA-04 (1-10; n = 13). Mean PK parameters were lower for children (AUC, Cmax , IVR; p = .02), while clearance was higher. Median (range) total dose of HFC for all BEs was 59.41 mg/kg (32.12-273.80) in adults/adolescents and was 24% higher (ns) in children at 73.91 mg/kg (47.45-262.50). Treatment was successful in 98.9% of the 89 BEs in adults/adolescents and in 100% of the 10 BEs in children, with comparable results for perioperative prophylaxis. CONCLUSION As expected, HFC PK differed between adults/adolescents and children. However, with the higher doses given to children, HFC showed similar efficacy across age groups. Dose adaptation based on age groups appears recommendable.
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Affiliation(s)
| | | | - Omid R. Zekavat
- Hematology Research CenterNemazee HospitalShiraz University of Medical SciencesShirazIran
| | - Irina Kruzhkova
- Research & Development DepartmentOctapharmaLachenSwitzerland
| | | | - Sigurd Knaub
- Research & Development DepartmentOctapharmaLachenSwitzerland
| | - Flora Peyvandi
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore PoliclinicoAngelo Bianchi Bonomi Hemophilia and Thrombosis CenterMilanItaly,Department of Pathophysiology and TransplantationUniversità degli Studi di MilanoMilanItaly
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Abstract
Congenital dysfibrinogenemia (CD) is caused by structural changes in fibrinogen that modify its function. Diagnosis is based on discrepancy between decreased fibrinogen activity and normal fibrinogen antigen levels and is confirmed by genetic testing. CD results from monoallelic mutations in fibrinogen genes leading to clinically heterogenous disorders. Most patients with CD are asymptomatic at time of diagnosis but the clinical course may be complicated by a tendency to bleeding and/or thrombosis. Patients with a thrombotic-related fibrinogen variant are particularly at risk and in such patients long-term anticoagulation should be considered. Management of surgery and pregnancy raise important and difficult issues. The mainstay of CD treatment remains fibrinogen supplementation. Antifibrinolytic agents are part of the treatment in some specific clinical settings. In this article, we discuss five clinical scenarios to highlight common clinical challenges. We detail our approach to establish a diagnosis of CD and discuss strategies for the management of bleeding, thrombosis, surgery and pregnancy.
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Blood, Sweat, and Fears: A Novel Mutation Associated With Anaphylaxis and Nonresponse in a Patient With Afibrinogenemia. J Pediatr Hematol Oncol 2021; 43:e260-e263. [PMID: 32341261 DOI: 10.1097/mph.0000000000001812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 04/01/2020] [Indexed: 01/15/2023]
Abstract
Congenital afibrinogenemia is a rare disorder characterized by a lack of detectable fibrinogen. The mainstay of treatment for acute bleeding episodes or perioperative management is replacement with fibrinogen concentrate or fibrinogen-containing blood products. The development of neutralizing antibodies and severe allergic reactions to fibrinogen replacement is rarely reported in afibrinogenemia patients. Here the treatment regimen is described for a 6-year-old girl with a severe allergic reaction to multiple fibrinogen-containing products who became refractory to treatment because of a presumed inhibitor to fibrinogen.
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Casini A, Neerman-Arbez M, de Moerloose P. Heterogeneity of congenital afibrinogenemia, from epidemiology to clinical consequences and management. Blood Rev 2020; 48:100793. [PMID: 33419567 DOI: 10.1016/j.blre.2020.100793] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 11/06/2020] [Accepted: 12/06/2020] [Indexed: 12/17/2022]
Abstract
Fibrinogen is a complex protein playing a major role in coagulation. Congenital afibrinogenemia, characterized by the complete absence of fibrinogen, is associated with major hemostatic defects. Even though the clinical course is unpredictable and can be completely different among patients, severe bleeding is the prominent symptom. Patients are also at increased risk of thrombosis and sometimes suffer from spontaneous spleen rupture, bone cysts and defective wound healing. Due to the relative rarity of afibrinogenemia, there are no evidence-based strategies for helping physicians in care of these patients. Fibrinogen supplementation is the keystone to prevent or treat bleeding events. In addition, fibrinogen, a pleiotropic protein with numerous physiological roles in immunity, angiogenesis and tissue repair, is involved in many diseases. Indeed, depletion of fibrinogen in animal models of infections, tumors and neurological diseases has an effect on the clinical course. The consequences for patients with afibrinogenemia still need to be investigated.
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Affiliation(s)
- Alessandro Casini
- Division of Angiology and Hemostasis, University Hospitals of Geneva, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205 Geneva, Switzerland.
| | - Marguerite Neerman-Arbez
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland.
| | - Philippe de Moerloose
- Faculty of Medicine, University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205 Geneva, Switzerland.
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Djambas Khayat C, Lohade S, D'Souza F, Shamanur LG, Zekavat OR, Kruzhkova I, Schwartz B, Solomon C, Knaub S, Peyvandi F. Efficacy and safety of fibrinogen concentrate for on-demand treatment of bleeding and surgical prophylaxis in paediatric patients with congenital fibrinogen deficiency. Haemophilia 2020; 27:283-292. [PMID: 33326665 PMCID: PMC8049000 DOI: 10.1111/hae.14230] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/18/2020] [Accepted: 11/25/2020] [Indexed: 12/12/2022]
Abstract
Background Congenital fibrinogen deficiency (CFD) is a rare, inherited disorder affecting normal blood clotting function, where patients can experience severe and/or frequent bleeding episodes (BEs). Treatment with human fibrinogen concentrate (HFC) can prevent/arrest bleeding. There is a need for more data on the efficacy, pharmacokinetics (PK) and safety of HFC treatment in paediatric patients with CFD. Methods Haemostatic efficacy of HFC (Fibryga®, Octapharma AG) for on‐demand treatment of bleeding and surgical prophylaxis in patients <12 years old was assessed by investigators and an Independent Data Monitoring and Endpoint Adjudication Committee (IDMEAC) based on an objective 4‐point efficacy scale. Maximum clot firmness (MCF; surrogate marker of haemostatic efficacy), single‐dose PK and safety were also assessed. Results Of 14 patients receiving HFC (median [range] age 6.0 years [1.0–10.0]), eight received HFC for 10 BEs, three for surgical prophylaxis and 13 for PK. The IDMEAC rated haemostatic efficacy as 100% successful for on‐demand BE treatment (95% CI 69.15–100.00) and surgical prophylaxis (95% CI 29.24–100.00). After a mean first dose of 70.78 mg/kg for BEs, mean (±SD) MCF significantly increased from pre‐treatment to 1‐hour post‐infusion (3.3 mm [±1.77]; P = 0.0002), coinciding with haemostatic efficacy. PK parameters were favourable. Two possibly related adverse events occurred, including one serious (portal vein thrombosis). No allergic/hypersensitivity reactions or deaths were observed. Conclusion HFC treatment for on‐demand treatment of BEs and surgical prophylaxis was efficacious for this ultra‐rare paediatric population with congenital afibrinogenaemia and showed a favourable PK and safety profile.
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Affiliation(s)
| | | | | | | | - Omid Reza Zekavat
- Hematology Research Center, Nemazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Irina Kruzhkova
- Research & Development Department, Octapharma, Lachen, Switzerland
| | - Bruce Schwartz
- Clinical Research & Development, Octapharma, Paramus, NJ, USA
| | - Cristina Solomon
- Research & Development Department, Octapharma, Lachen, Switzerland
| | - Sigurd Knaub
- Research & Development Department, Octapharma, Lachen, Switzerland
| | - Flora Peyvandi
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center and Fondazione Luigi Villa, Milan, Italy
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Bellon A, Fuseau E, Roumanie O, Lamazure J, Stevens W, Dahmane A, Barthez-Toullec M, Golly D, Henriet C, Bridey F. Population pharmacokinetics of a triple-secured fibrinogen concentrate administered to afibrinogenaemic patients: Observed age- and body weight-related differences and consequences for dose adjustment in children. Br J Clin Pharmacol 2020; 86:329-337. [PMID: 31658379 PMCID: PMC7015754 DOI: 10.1111/bcp.14147] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 09/09/2019] [Accepted: 09/21/2019] [Indexed: 11/28/2022] Open
Abstract
Aims The pharmacokinetics (PK) of a triple‐secured fibrinogen concentrate (FC) was assessed in patients ≥40 kg by noncompartmental analysis over a period of 14 days with multiple blood samples. Limited PK time point assessments in children lead to consideration of using Bayesian estimation for paediatric data. The objectives were (i) to define the population PK of FC in patients with afibrinogenaemia; (ii) to detect age‐ and body weight‐related differences and consequences for dose adjustment. Methods A population PK model was built using plasma fibrinogen activity data collected in 31 patients aged 1 to 48 years who had participated in a single‐dose PK study with FC 0.06 g kg–1. Results A 1‐compartment model with allometric scaling accounting for body weight was found to best describe the kinetics of FC. Addition of age and sex as covariates did not improve the model. Incremental in vivo recovery assessed at the end of infusion with the predicted maximal concentrations was lower, weight‐adjusted clearance was higher, and fibrinogen elimination half‐life was shorter in patients <40 kg than patients ≥40 kg. Interpatient variability was similar in both groups. Conclusion Dosing in patients ≥40 kg based on the previous empirical finding using noncompartmental analysis where FC 1 g kg–1 raises the plasma fibrinogen activity by 23 g L–1 was confirmed. In patients <40 kg, (covering the age range from birth up to about 12 years old) FC 1 g kg–1 raises the plasma fibrinogen by 19 g L–1. Dosing should be adapted accordingly unless therapy is individualized.
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Affiliation(s)
- Anne Bellon
- Clinical Development, Laboratoire français du Fractionnement et des Biotechnologies (LFB), Les Ulis, France
| | | | | | - Jennifer Lamazure
- Clinical Development, Laboratoire français du Fractionnement et des Biotechnologies (LFB), Les Ulis, France
| | - Wil Stevens
- Clinical Development, Laboratoire français du Fractionnement et des Biotechnologies (LFB), Les Ulis, France
| | - Amel Dahmane
- Clinical Development, Laboratoire français du Fractionnement et des Biotechnologies (LFB), Les Ulis, France
| | - Malika Barthez-Toullec
- Clinical Development, Laboratoire français du Fractionnement et des Biotechnologies (LFB), Les Ulis, France
| | - Dominique Golly
- Clinical Development, Laboratoire français du Fractionnement et des Biotechnologies (LFB), Les Ulis, France
| | - Céline Henriet
- Clinical Development, Laboratoire français du Fractionnement et des Biotechnologies (LFB), Les Ulis, France
| | - Françoise Bridey
- Clinical Development, Laboratoire français du Fractionnement et des Biotechnologies (LFB), Les Ulis, France
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