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Clinical Trial Details — Status: Not yet recruiting

Administrative data

NCT number NCT04590950
Other study ID # APHP191124
Secondary ID
Status Not yet recruiting
Phase
First received
Last updated
Start date October 2020
Est. completion date December 2021

Study information

Verified date August 2020
Source Assistance Publique - Hôpitaux de Paris
Contact Georges JOURDI, PharmD, PhD
Phone 00 33 1 58 41 20 05
Email georges.jourdi@aphp.fr
Is FDA regulated No
Health authority
Study type Observational

Clinical Trial Summary

The purpose of this study is to evaluate the performance of different methods for measuring factor IX activity levels in haemophilia B patients treated with eftrenonacog-alfa and assess its pharmacodynamics (PD) in a real-life setting.


Description:

A recent European survey showed that increasing number of hemophilia B patients was switched from standard to extended half-life drugs. While some clinicians currently prefer to treat empirically rather than based on laboratory results, adoption of replacement therapy based on extended half-life products such as eftrenonacog-alfa may increase the interest in individualized pharmacokinetic assessments allowing the development of an initial dosing regimen. Thus inaccurate FIX activity measurements might be critical, especially when FIX trough level is used to tailor patient dosing regimens. It is therefore important that FIX activity levels are accurately determined allowing adequate recovery without increasing the cost of medical management of hemophilia B patients due to unnecessary dose corrections. With the expansion of the prescription of eftrenonacog-alfa, the problem of accurately measuring its recovery has risen within hemostasis laboratories. Chronometric one-stage assays (OSA) are currently the most widely performed tests for FIX activity measurement. They are based on activated partial thromboplastin time (aPTT) reagent and factor-deficient plasma. Various aPTT reagents are commercialized. They could lead to a substantial variability in FIX results. Chromogenic two-stage assays (CSA) are less frequently used in clinical laboratories. They present fewer reagent choice compared to OSA. Several studies have evaluated OSA and CSA performances in samples spiked with eftrenonacog-alfa and have evidenced that some commonly used aPTT reagents would not be suitable for accurately monitoring this product. Whether these results are commutable to post-infusion samples collected from real-life patients remains unclear. Unlike the measurement of a unique coagulation factor activity, thrombin generation assay (TGA) is a dynamic global test that explores the coagulation cascade as well as the anticoagulant pathways. TGA could be therefore a valuable tool to monitor replacement therapy in hemophilia B patients. Hence the investigators sought in a real-life setting to compare 2 CSA and 1 OSA reagents to a product specific OSA in severe hemophilia B patients supplemented with eftrenonacog-alfa. The investigators also aimed to evaluate the pharmacodynamics (PD) of eftrenonacog-alfa using TGA.


Recruitment information / eligibility

Status Not yet recruiting
Enrollment 15
Est. completion date December 2021
Est. primary completion date December 2020
Accepts healthy volunteers No
Gender All
Age group 18 Years and older
Eligibility Inclusion Criteria: - severe haemophilia B patients - treated with eftrenonacog-alfa Exclusion Criteria: - any other haemostatic or replacement therapy

Study Design


Related Conditions & MeSH terms


Intervention

Other:
Non interventional study
Non interventional study

Locations

Country Name City State
France Service d'hématologie biologique - Hôpital Cochin Paris

Sponsors (1)

Lead Sponsor Collaborator
Assistance Publique - Hôpitaux de Paris

Country where clinical trial is conducted

France, 

References & Publications (7)

Bowyer AE, Shepherd MF, Kitchen S, Maclean RM, Makris M. Measurement of extended half-life recombinant factor IX products in clinical practice. Int J Lab Hematol. 2019 Apr;41(2):e46-e49. doi: 10.1111/ijlh.12953. Epub 2018 Dec 7. — View Citation

Collins PW, Fischer K, Morfini M, Blanchette VS, Björkman S; International Prophylaxis Study Group Pharmacokinetics Expert Working Group. Implications of coagulation factor VIII and IX pharmacokinetics in the prophylactic treatment of haemophilia. Haemophilia. 2011 Jan;17(1):2-10. doi: 10.1111/j.1365-2516.2010.02370.x. Epub 2010 Aug 22. Review. — View Citation

Dargaud Y, Béguin S, Lienhart A, Al Dieri R, Trzeciak C, Bordet JC, Hemker HC, Negrier C. Evaluation of thrombin generating capacity in plasma from patients with haemophilia A and B. Thromb Haemost. 2005 Mar;93(3):475-80. — View Citation

Kitchen S, Tiefenbacher S, Gosselin R. Factor Activity Assays for Monitoring Extended Half-Life FVIII and Factor IX Replacement Therapies. Semin Thromb Hemost. 2017 Apr;43(3):331-337. doi: 10.1055/s-0037-1598058. Epub 2017 Mar 6. Review. — View Citation

Peyvandi F, Garagiola I, Boscarino M, Ryan A, Hermans C, Makris M. Real-life experience in switching to new extended half-life products at European haemophilia centres. Haemophilia. 2019 Nov;25(6):946-952. doi: 10.1111/hae.13834. Epub 2019 Aug 16. — View Citation

Sommer JM, Buyue Y, Bardan S, Peters RT, Jiang H, Kamphaus GD, Gray E, Pierce GF. Comparative field study: impact of laboratory assay variability on the assessment of recombinant factor IX Fc fusion protein (rFIXFc) activity. Thromb Haemost. 2014 Nov;112(5):932-40. doi: 10.1160/TH13-11-0971. Epub 2014 Aug 21. — View Citation

Srivastava A, Brewer AK, Mauser-Bunschoten EP, Key NS, Kitchen S, Llinas A, Ludlam CA, Mahlangu JN, Mulder K, Poon MC, Street A; Treatment Guidelines Working Group on Behalf of The World Federation Of Hemophilia. Guidelines for the management of hemophilia. Haemophilia. 2013 Jan;19(1):e1-47. doi: 10.1111/j.1365-2516.2012.02909.x. Epub 2012 Jul 6. — View Citation

Outcome

Type Measure Description Time frame Safety issue
Primary FIX activity levels 2 chromogenic assays (Bio phen FIX and Rox FIX) and 2 chronometric assays (CK Prest with standard human plasma or FIX deficient plasma supplemented with eftrenonacog-alfa as calibrators) One month
Secondary Thrombin generation assay Thrombin generation assay is performed using a microplate fluorometer. Plasma samples are run using 20 µL low phospholipids reagent (PPP-reagent) (1 µM tissue factor and 4 micromoles (µM )phospholipid vesicles) or 20 µL Thrombin Calibrator. Assay is initiated by auto dispensing 20 µL of Fluo-Substrate solution containing calcium ions and fluorogenic substrate, Z-Gly-Gly-Arg-7-amino-4-methylcoumarin. Generated thrombin cleaves the substrate and fluorescence increase is monitored at 37 °C for 60 min with a measurement every 20 seconds.
Thrombin scope®, version 5.0.0.742 is used to calculate the amount of thrombin generated over time taking into account for each sample the calibrator activity. Consequently, five parameters are reported by the Thrombin scope® the fist is lag time (LT; in min)
One month
Secondary Thrombin generation assay microplate fluorometer, time to peak One month
Secondary Thrombin generation assay microplate fluorometer, peak height One month
Secondary Thrombin generation assay microplate fluorometer, endogenous thrombin potential One month
Secondary Thrombin generation assay microplate fluorometer, velocity One month