Read by QxMD icon Read


Mirella Ezban, Mette Brunsgaard Hermit, Egon Persson
N9-GP (nonacog beta pegol; Refixia® ; Rebinyn® , Novo Nordisk A/S, Bagsvaerd, Denmark) is a glycoPEGylated extended half-life recombinant factor IX (rFIX) that exhibits efficacy and potency comparable to unmodified FIX molecules in non-clinical models. Phase 3 clinical trials have confirmed the efficacy and tolerability of N9-GP for the prevention and on-demand treatment of bleeding episodes in patients with haemophilia B. Recent studies have shown that PEGylation affects clotting times in activated partial thromboplastin time (aPTT)-based one-stage activity assays due to interaction between the FIX molecule and certain aPTT reagents...
January 2019: Haemophilia: the Official Journal of the World Federation of Hemophilia
Sandra Le Quellec, Nathalie Enjolras, Eloïse Perot, Jonathan Girard, Claude Negrier, Yesim Dargaud
Prophylaxis is currently considered the optimal care for severe haemophilia. For patients and their families one of the major difficulties with prophylaxis is the need for frequent venipunctures. The half-life of standard factor IX (FIX) concentrates is approximately 18 hours, which requires 2 or 3 intravenous infusions per week to achieve bleeding prevention in patients with severe haemophilia B. Prolonging the half-life of FIX can therefore reduce the frequency of infusions. Recently, extended half-life recombinant FIX (rFIX) concentrates have been developed...
November 19, 2018: Thrombosis and Haemostasis
Carsten Horn, Claude Négrier, Uwe Kalina, Wilfried Seifert, Kenneth D Friedman
BACKGROUND: Measuring factor IX activity (FIX:C) with one-stage clotting (OSC) assays, based on the activated partial thromboplastin time (aPTT), is the current mainstay of diagnostic techniques for hemophilia B. Assessing the performance of new recombinant FIX (rFIX) products in OSC assays is essential as aPTT reagents from different manufacturers yield different potency estimates for rFIX. OBJECTIVES: To evaluate the extent to which choice of reagent composition influences rFIX potency measurements of recombinant FIX-albumin fusion protein (rIX-FP, IDELVION® ) activity in OSC assays...
November 12, 2018: Journal of Thrombosis and Haemostasis: JTH
Johnny N Mahlangu
Whilst the global prevalence of haemophilia B is less than that of haemophilia A, rapid and remarkable innovations have been made in the development of haemophilia B therapies in the last decade. The most recent developments are the evolution of extended half-life haemophilia B replacement therapies which are designed to reduce the treatment burden associated with prophylactic infusion of factor IX (FIX) to prevent bleeding in haemophilia B participants. Clinical development programmes have culminated in the completion of three phase III studies on extended half-life (EHL) recombinant FIX (rFIX) products and subsequent approval and registration of these in many countries around the world...
November 2018: Therapeutic Advances in Hematology
Elena Santagostino, Maria Elisa Mancuso
Decisions over hemophilia treatment selection and switching involve balancing many clinical and patient-related factors. The current standard of care for patients with hemophilia B is prophylaxis with plasma-derived or recombinant factor IX (rFIX) concentrates. However, several extended half-life (EHL) rFIX products have recently been developed to improve treatment convenience and clinical outcomes for these patients. Nonacog beta pegol, an rFIX product that combines the FIX protein with a 40 kDa polyethylene glycol moiety, has been evaluated in 115 previously treated patients with hemophilia B (including 25 children) in the paradigm clinical trial program...
2018: Drug Design, Development and Therapy
Bryn Kastetter, Amanda B Matrai, Brian C Cooley
: The murine FeCl3 model is a widely used model for studying arterial thrombosis, yet provides limited information from each mouse, often only a single time point for the onset of occlusion (defined as the time to occlusion; TTO). To optimize data from the murine ferric chloride model of thrombosis. FeCl3 injury was induced in the carotid arteries of wild-type and Factor IX (FIX) knockout mice, with infusion of recombinant FIX (rFIX) to normalize FIX deficiency at various times around FeCl3 injury. The TTO was recorded as a percentage of baseline flow as occlusion continued to zero flow, with identification of reflow events...
November 2018: Blood Coagulation & Fibrinolysis: An International Journal in Haemostasis and Thrombosis
Helen V Wilmot, Elaine Gray
The activated partial thromboplastin time (APTT) one-stage clotting (OSC) assay is used to potency label factor IX (FIX) therapeutics and to monitor the treatment of deficient patients. Studies have highlighted differences in potency estimates for FIX therapeutics depending on what activator type the APTT reagent contains. During the study to replace the 4th International Standard (IS) for FIX Concentrate, it was noted that for the recombinant FIX (rFIX) candidates, a potency difference of 20% was obtained by some between laboratories using the reagent DAPTTIN...
September 2018: Haemophilia: the Official Journal of the World Federation of Hemophilia
S Pignani, A Todaro, M Ferrarese, S Marchi, S Lombardi, D Balestra, P Pinton, F Bernardi, M Pinotti, A Branchini
Essentials Missense mutations often impair protein folding, and thus intracellular trafficking and secretion. Cellular models of severe type I hemophilia B were challenged with chaperone-like compounds. Sodium phenylbutyrate improved intracellular trafficking and secretion of the frequent p.R294Q. The increased coagulant activity levels (∼3%) of p.R294Q would ameliorate the bleeding phenotype. SUMMARY: Background Missense mutations often impair protein folding and intracellular processing, which can be improved by small compounds with chaperone-like activity...
October 2018: Journal of Thrombosis and Haemostasis: JTH
Giancarlo Castaman
The health benefits of prophylactic dosing regimens for clotting factor therapy in patients with hemophilia include reduced joint damage and improved quality of life; as such, prophylaxis is recommended in treatment guidelines. However, many patients with hemophilia B are treated on demand, and prophylaxis has been utilized less frequently than in hemophilia A. Areas covered: This review discusses the opportunities and evidence for prophylaxis in hemophilia B, in the context of treatment guidelines and with regard to factor IX (FIX) replacement therapies, including long-acting recombinant FIX (rFIX)...
August 2018: Expert Review of Hematology
C Wang, G Young
INTRODUCTION: Although clinical trials have demonstrated extended half-life (EHL) VIII and IX fusion proteins to be safe and efficacious in patients with haemophilia A and B, studies on real-world clinical application have not been performed. AIM: To retrospectively examine the real-world experience of rFVIII Fc and rFIX Fc in patients. METHODS: A retrospective review of existing medical records of patients with haemophilia A or haemophilia B who had been prescribed rFVIII Fc or rFIX Fc was conducted from the Children's Hospital Los Angeles Haemostasis and Thrombosis Centre database...
May 2018: Haemophilia: the Official Journal of the World Federation of Hemophilia
Yvonne Brennan, Jennifer Curnow, Emmanuel J Favaloro
Current treatment for hemophilia B involves replacing the missing coagulation factor IX (FIX) with either plasma-derived or recombinant (r) FIX. Trenonacog alfa is the third normal half-life rFIX that has been granted FDA approval. Area covered: In this review, the authors examine trenonacog alfa for the treatment of hemophilia B including prophylaxis, on-demand and perioperative hemostasis. They compare the PK profile to nonacog alfa and evaluate the drug's efficacy and safety from published studies. Expert opinion: Trenonacog alfa appears to be an effective and safe treatment option for patients with hemophilia B with a PK profile similar to that of nonacog alfa...
January 2018: Expert Opinion on Biological Therapy
Massimo Morfini
Hemophilia A is the most frequent inherited bleeding disorder and most challenging coagulation disorder. To combat this, a number of new improved rFVIII/IX concentrates have recently been approved. Some of them are derived from protein fusion biotechnology or pegylation to extend their half-life (HL). However, prophylaxis has become a standard of care to prevent arthropathy in hemophiliacs though the need of frequent venipunctures is a major obstacle to primary prophylaxis. The new Extended Half-Life (EHL) rFIX concentrates allow increased intervals, while the improved HL of new rFVIII was moderate...
December 2017: Expert Opinion on Biological Therapy
Youngsuk Seo, Gyeong Mi Park, Myung Jin Oh, Hyun Joo An
AIM: Recombinant coagulation factor IX (rFIX) has extraordinarily multiple post-translational modifications including N-glycosylation and O-glycosylation which have a drastic effect on biological functions and in vivo recovery. Unlike N-glycosylation extensively characterized, there are a few studies on O-glycosylation due to its intrinsic complexity. In-depth O-glycosylation analysis is necessary to better understand and assess pharmacological activity of rFIX. RESULTS: We determined unusual O-glycosylations including O-fucosylation and O-glucosylation which were located at Serine 53 and 61, respectively in EGF domain...
September 2017: Bioanalysis
Daniel A Ribeiro, Douglas F Passos, Helen C Ferraz, Leda R Castilho
This work investigated the use of hydrophobic interaction membrane chromatography for intermediate purification of recombinant human Factor IX (rFIX) produced by CHO cells. The first purification step was based on a strong anion exchange monolith, thus forming a purification process fully based on convective media, which allow operation at high flow rates and low pressure drops, as well as modular scale-up. Although the starting material was challenging (CHO cell culture supernatant harvested at 70% cell viability), the two-step purification process showed promising results, with a global purification factor of 298, a global recovery of 69%, and DNA and endotoxin levels close to regulatory limits...
November 2017: Electrophoresis
P W Collins, D V K Quon, M Makris, P Chowdary, C L Kempton, S J Apte, M V Ramanan, C R M Hay, B Drobic, Y Hua, T J Babinchak, E D Gomperts
INTRODUCTION: Trenonacog alfa (IB1001) is a recombinant factor IX (rFIX) manufactured in Chinese hamster ovary (CHO) cells. IB1001 was evaluated in a multicentre clinical trial with haemophilia B patients. AIM: The aim was to establish IB1001 pharmacokinetic non-inferiority to comparator rFIX, safety and efficacy in previously treated patients (PTPs) with haemophilia B. METHODS: Subjects were severe or moderately severe haemophilia B adult and adolescent PTPs with no history of FIX inhibitors...
January 2018: Haemophilia: the Official Journal of the World Federation of Hemophilia
T Preijers, H C A M Hazendonk, K Fijnvandraat, F W G Leebeek, M H Cnossen, R A A Mathôt
Essentials Individual pharmacokinetic (PK) parameters can be obtained by limited sampling strategies (LSSs). Following 100 IU kg-1 rFIX, LSSs with 1 to 3 samples were evaluated in 5000 simulated subjects. For all LSSs, estimated individual PK parameters showed acceptable bias and precision. One sample between 10 min-3 h and two between 48 h-56 h showed best predictive performance. SUMMARY: Background Patients with severe hemophilia B regularly administer prophylactic intravenous doses of clotting factor IX concentrate to maintain a trough level of at least 0...
September 2017: Journal of Thrombosis and Haemostasis: JTH
Aline G Almeida, Rodrigo C V Pinto, C Mark Smales, Leda R Castilho
OBJECTIVES: To develop a recombinant human factor IX (rFIX) formulation equivalent to commercially available products in terms of cake appearance, residual moisture, proportion of soluble aggregates and activity maintenance for 3 months at 4-8 °C. RESULTS: NaCl and low bulking agent/cryoprotectant mass ratio had a negative impact on cake quality upon lyophilisation for a wide range of formulations tested. Particular devised formulations maintained rFIX activity after lyophilization with a similar performance when compared with the rFIX formulated using the excipients reported for a commercially available FIX formulation (Benefix)...
August 2017: Biotechnology Letters
V Nummi, A Jouppila, R Lassila
INTRODUCTION: Prophylaxis is the recommended treatment mode for severe hemophilia B. However, no single treatment regimen fits for all patients. Once-weekly prophylaxis with high-dose recombinant factor IX (rFIX) is efficacious, nevertheless, laboratory outcomes following 72 h after administration are lacking. METHODS: In a prospective open-label noncomparative study, 10 severe/moderate (FIX ≤2 IU/dL) adult patients received rFIX dose (60-100 IU/kg) after >72 h washout on two occasions, separated by 7 days...
August 2017: International Journal of Laboratory Hematology
Alfonso Iorio, Kathelijn Fischer, Victor Blanchette, Savita Rangarajan, Guy Young, Massimo Morfini
The prophylactic administration of factor IX (FIX) is considered the most effective treatment for haemophilia B. The inter-individual variability and complexity of the pharmacokinetics (PK) of FIX, and the rarity of the disease have hampered identification of an optimal treatment regimens. The recent introduction of extended half-life recombinant FIX molecules (EHL-rFIX), has prompted a thorough reassessment of the clinical efficacy, PK and pharmacodynamics of plasma-derived and recombinant FIX. First, using longer sampling times and multi-compartmental PK models has led to more precise (and favourable) PK for FIX than was appreciated in the past...
June 2, 2017: Thrombosis and Haemostasis
Alessio Branchini, Mattia Ferrarese, Matteo Campioni, Giancarlo Castaman, Rosella Mari, Francesco Bernardi, Mirko Pinotti
Drug-induced readthrough over premature stop codons (PTCs) is a potentially attractive therapy for genetic disorders, but a wide outcome variability has been observed. Through expression studies, we investigated the responsiveness to the readthrough-inducing drug geneticin of 11 rationally selected factor IX (FIX) nonsense mutations, present in 70% (324/469) of hemophilia B (HB) patients with PTCs. Among the predicted readthrough-permissive TGA variants, only 2 (p.W240X and p.R384X) responded with a remarkable rescue of FIX activity...
April 20, 2017: Blood
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"