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St Ledger K, Feussner A, Kalina U, Horn C, Metzner HJ, Bensen-Kennedy D, Blackman N, Veldman A, Stowers A, Friedman KD. International comparative field study evaluating the assay performance of AFSTYLA in plasma samples at clinical hemostasis laboratories. J Thromb Haemost 2018; 16:555-564. [PMID: 29274194 DOI: 10.1111/jth.13932] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Indexed: 02/07/2023]
Abstract
Essentials AFSTYLA exhibits ≈50% underestimation in activity when the one-stage (OS) assay is utilized. A field study compared the performance of AFSTYLA with Advate in factor VIII activity assays. AFSTYLA activity can be monitored with both the chromogenic substrate and the OS assay. The consistent OS underestimation allows for a conversion factor to be applied to OS results. SUMMARY Introduction AFSTYLA (antihemophilic factor [recombinant] single chain) is a novel B-domain truncated recombinant factor VIII (rFVIII). For AFSTYLA, an approximate 50% discrepancy was observed between results of the one-stage (OS) and chromogenic substrate (ChS) FVIII activity assays. An investigation was undertaken to test whether there is a linear relationship between ChS and OS assay results that would allow reliable clinical interpretation of results independent of the assay method used. Aims To provide confidence in future clinical monitoring, this field study investigated the performance of AFSTYLA and a full-length rFVIII (Advate® ) in FVIII activity assays routinely performed in clinical laboratories. Methods The comparison of AFSTYLA and Advate was performed in an international, multicenter and blinded field study of simulated post-infusion samples. The study documented the extent of variability between methods and laboratories and characterized the relationship between the ChS and OS assays. Results Results from 23 laboratories demonstrate that intra and interlaboratory variability in OS assays were similar for both products. When comparing within the OS assay format, there was a similar and reagent-correlated variability in response to different activators for both AFSTYLA and Advate. The OS underestimation was highly predictable and consistent across the complete range of FVIII plasma concentrations. Conclusion Post-infusion plasma AFSTYLA levels can be monitored in patients by the OS and ChS assays. The consistent and predictable difference between the two assay formats provides clinicians with adequate guidance on how to interpret the results of the OS assay using a single conversion factor.
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Affiliation(s)
- K St Ledger
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
- Clinical R&D, CSL Behring, Marburg, Germany
| | - A Feussner
- Pre-clinical R&D, CSL Behring, Marburg, Germany
| | - U Kalina
- Pre-clinical R&D, CSL Behring, Marburg, Germany
| | - C Horn
- Pre-clinical R&D, CSL Behring, Marburg, Germany
| | - H J Metzner
- Pre-clinical R&D, CSL Behring, Marburg, Germany
| | - D Bensen-Kennedy
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
- Clinical R&D, CSL Behring, Marburg, Germany
| | - N Blackman
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
| | - A Veldman
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
| | - A Stowers
- Pre-clinical R&D, CSL Behring, Marburg, Germany
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Stasyshyn O, Djambas Khayat C, Iosava G, Ong J, Abdul Karim F, Fischer K, Veldman A, Blackman N, St Ledger K, Pabinger I. Safety, efficacy and pharmacokinetics of rVIII-SingleChain in children with severe hemophilia A: results of a multicenter clinical trial. J Thromb Haemost 2017; 15:636-644. [PMID: 28166608 DOI: 10.1111/jth.13647] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Indexed: 08/31/2023]
Abstract
Essentials rVIII-SingleChain is a novel recombinant factor VIII with covalently bonded heavy and light chains. Efficacy, safety and pharmacokinetics were studied in pediatric patients with severe hemophilia A. Across all prophylaxis regimens, the median annualized spontaneous bleeding rate was 0.00. rVIII-SingleChain showed excellent hemostatic efficacy and a favorable safety profile. SUMMARY Background rVIII-SingleChain is a novel B-domain truncated recombinant factor VIII (rFVIII) comprised of covalently bonded FVIII heavy and light chains, demonstrating a high binding affinity to von Willebrand factor. Objectives This phase III study investigated the safety, efficacy and pharmacokinetics of rVIII-SingleChain in previously treated pediatric patients < 12 years of age with severe hemophilia A. Patients/Methods Patients could be assigned to prophylaxis or on-demand therapy by the investigator. For patients assigned to prophylaxis, the treatment regimen and dose were based on the bleeding phenotype. For patients receiving on-demand therapy, dosing was guided by World Federation of Hemophilia recommendations. The primary endpoint was treatment success, defined as a rating of 'excellent' or 'good' on the investigator's clinical assessment of hemostatic efficacy for all treated bleeding events. Results The study enrolled 84 patients (0 to < 6 years, n = 35; ≥ 6 to < 12 years, n = 49); 81 were assigned to prophylaxis and three to an on-demand regimen. Patients accumulated a total of 5239 exposure days (EDs), with 65 participants reaching > 50 EDs. In the 347 bleeds treated and evaluated by the investigator, hemostatic efficacy was rated as excellent or good in 96.3%. The median annualized spontaneous bleeding rate was 0.00 (Q1, Q3: 0.00, 2.20), and the median annualized bleeding rate was 3.69 (Q1, Q3: 0.00, 7.20) across all prophylaxis regimens. No participant developed an inhibitor. Conclusions rVIII-SingleChain is a novel rFVIII molecule showing excellent hemostatic efficacy and a favorable safety profile in a clinical study in children < 12 years of age with severe hemophilia A.
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Affiliation(s)
- O Stasyshyn
- Institute of Blood Pathology and Transfusion Medicine, National Academy of Medical Sciences of Ukraine, Lviv, Ukraine
| | - C Djambas Khayat
- Lebanon Department of Pediatrics, Hotel Dieu de France Hospital, Beirut, Lebanon
| | - G Iosava
- JSC Scientific-Research Institute of Hematology and Transfusiology, Tbilisi, Georgia
| | - J Ong
- Brokenshire Integrated Health Ministries, Inc., Davao, Philippines
| | - F Abdul Karim
- Hemophilia Clinic, National Blood Centre, Kuala Lumpur, Malaysia
| | - K Fischer
- Van Creveldkliniek, University Medical Center Utrecht, Utrecht, the Netherlands
| | - A Veldman
- Clinical R&D, CSL Behring, Marburg, Germany
| | - N Blackman
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
| | - K St Ledger
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
| | - I Pabinger
- Clinical Division of Haematology and Haemostaseology, Department of Medicine I, Medical University Vienna, Vienna, Austria
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Klamroth R, Simpson M, von Depka-Prondzinski M, Gill JC, Morfini M, Powell JS, Santagostino E, Davis J, Huth-Kühne A, Leissinger C, Neumeister P, Bensen-Kennedy D, Feussner A, Limsakun T, Zhou M, Veldman A, St Ledger K, Blackman N, Pabinger I. Comparative pharmacokinetics of rVIII-SingleChain and octocog alfa (Advate(®) ) in patients with severe haemophilia A. Haemophilia 2016; 22:730-8. [PMID: 27434619 DOI: 10.1111/hae.12985] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/25/2016] [Indexed: 01/16/2023]
Abstract
BACKGROUND rVIII-SingleChain, a novel recombinant factor VIII (rFVIII), has been designed as a B-domain truncated construct with covalently bonded heavy and light chains, aiming to increase binding affinity to von Willebrand factor (VWF). Preclinical studies confirmed greater affinity for VWF, giving improved pharmacokinetic and pharmacodynamic properties compared with full-length rFVIII. AIM To investigate the pharmacokinetics of rVIII-SingleChain and compare them against those of full-length rFVIII. METHODS This study enrolled 27 patients with severe haemophilia A in the AFFINITY clinical trial programme. After a 4-day washout period, all patients received a single infusion of 50 IU kg(-1) octocog alfa (Advate(®) ); after a ≥4-day postinfusion washout period, they received a single infusion of 50 IU kg(-1) rVIII-SingleChain. Blood samples for pharmacokinetic assessments of each product were collected before infusion (predose) and at 0.5, 1, 4, 8, 10, 24, 32, 48 and 72 h postinfusion for both products. RESULTS rVIII-SingleChain had a longer mean half-life (t1/2 ) (14.5 vs. 13.3 h), lower mean clearance (CL) (2.64 vs. 3.68 mL h(-1) kg(-1) ), higher mean residence time (20.4 vs. 17.1 h) and larger mean AUCinf (2090 vs. 1550 IU?h dL(-1) ) than octocog alfa, respectively. The mean AUCinf after rVIII-SingleChain infusion was ~35% larger than after octocog alfa. A similar pattern was observed for AUC0-last . No serious adverse events or inhibitors were reported. CONCLUSIONS rVIII-SingleChain has a favourable pharmacokinetic profile compared with octocog alfa and was well tolerated. The prolonged t1/2 , larger AUC and reduced CL of rVIII-SingleChain may permit longer dosing intervals, thereby improving patient adherence to prophylactic treatment.
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Affiliation(s)
- R Klamroth
- Department for Internal Medicine, Vascular Medicine and Haemostaseology, Vivantes Klinikum, Berlin Friedrichshain, Germany
| | - M Simpson
- Rush University Medical Center, Chicago, IL, USA
| | | | - J C Gill
- Medical College of Wisconsin and Blood Center of Wisconsin, Milwaukee, WI, USA
| | - M Morfini
- Ospedaliero Universitaria Careggi, Firenze, Italy
| | - J S Powell
- Hemophilia Treatment Center, UC Davis, Sacramento, CA, USA
| | - E Santagostino
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, IRCCS Fondazione Ca' Granda, Ospedale Maggiore Policlinico, Milano, Italy
| | - J Davis
- University of Miami Hemophilia Treatment Center, Miami, FL, USA
| | - A Huth-Kühne
- Hämophiliezentrum und Gerinnungsambulanz SRH Kurpfalzkrankenhaus, Heidelberg, Germany
| | - C Leissinger
- Louisiana Center for Bleeding and Clotting Disorders, New Orleans, LA, USA
| | - P Neumeister
- Klinische Abteilung für Hämatologie, Medizinische Universität of Graz, Graz, Austria
| | | | - A Feussner
- Clinical R&D, CSL Behring, Marburg, Germany
| | - T Limsakun
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
| | - M Zhou
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
| | - A Veldman
- Clinical R&D, CSL Behring, Marburg, Germany
| | - K St Ledger
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
| | - N Blackman
- Clinical R&D, CSL Behring, King of Prussia, PA, USA
| | - I Pabinger
- Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria.
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Fonseca DB, Sheehy MRJ, Blackman N, Shelton PMJ, Prior AE. Reversal of a hallmark of brain ageing: lipofuscin accumulation. Neurobiol Aging 2005; 26:69-76. [PMID: 15585347 DOI: 10.1016/j.neurobiolaging.2004.02.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2003] [Revised: 01/15/2004] [Accepted: 02/24/2004] [Indexed: 10/26/2022]
Abstract
The prospect of removing cellular deposits of lipofuscin is of considerable interest because they may contribute to age related functional decline and disease. Here, we use a decapod crustacean model to circumvent a number of problems inherent in previous studies on lipofuscin loss. We employ (a) validated lipofuscin quantification methods, (b) an in vivo context, (c) essentially natural environmental conditions and (d) a situation without accelerated production of residual material or (e) application of pharmacological compounds. We use a novel CNS biopsy technique that produces both an anti-ageing effect and also permits longitudinal sampling of individuals, thus (f) avoiding conventional purely cross-sectional population data that may suffer from selective mortality biases. We quantitatively demonstrate that lipofuscin, accrued through normal ageing, can be lost from neural tissue. The mechanism of loss probably involves exocytosis and possibly blood transport. If non-disruptive ways to accelerate lipofuscin removal can be found, our results suggest that therapeutic reversal of this most universal manifestation of cellular ageing may be possible.
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Affiliation(s)
- D B Fonseca
- Department of Biology, University of Leicester, University Road, Leicester LE1 7RH, UK.
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Affiliation(s)
- K. Lake
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019
| | - M. Dorrell
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019
| | - N. Blackman
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019
| | - M. A. Khan
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019
| | - K. M. Nicholas
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019
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Hennen BK, Blackman N. Teaching About Culture and Health in Ontario Medical Schools: Learning about culture and health through patient-centered care. Can Fam Physician 1992; 38:1123-1129. [PMID: 21221329 PMCID: PMC2145865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Questionnaire surveys and on-site visits determined that culture and health are not a formal part of a curriculum for all students in any undergraduate or family medicine residency program in Ontario medical schools. Electives and other opportunities exist, but only some students benefit. Suggestions from the programs on how to improve such learning and make it universally available are noted. Patient-centered care is endorsed as a suitable model for learning about culture and health in the context of community teaching practices.
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Karpas CM, Blackman N. Adenocarcinoma arising in a hamartoma (adenolipomyoma) of the bronchus associated with multiple benign tumors. Reort of a case. Am J Clin Pathol 1967; 48:383-8. [PMID: 6053926 DOI: 10.1093/ajcp/48.4.383] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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