Stability and Sterility of Sucrose-Formulated Recombinant Factor VIII (Kogenate® FS/Bayer) for Use during Continuous Infusion.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 4004-4004
Author(s):  
Lisa Regan ◽  
Jordan Chew ◽  
Khang Vo ◽  
Joyce Leveque ◽  
Naji Khabbaz ◽  
...  

Abstract Continuous infusion of factor VIII (FVIII) is an alternative treatment approach to bolus dosing for providing hemostatic control in patients with hemophilia A undergoing surgery. Continuous infusion maintains consistent circulating FVIII, thus avoiding wastefully high or dangerously low levels. Potential advantages of continuous infusion include improved protection from excessive bleeding, reduced factor consumption, and easier monitoring. Continuous infusion requires FVIII usage parameters that are typically outside of the tested and approved ranges for the product, including extended time in an aqueous state at room temperature and exposure to a large surface area of tubing. Here we present in vitro data on the stability and sterility of a sucrose-formulated recombinant FVIII product (Kogenate® FS/Bayer; rFVIII-FS) under conditions comparable to those that would be experienced during the continuous infusion of patients. Three lots for each of 3 vial sizes (250, 500, and 1000 IU) were tested. Twenty vials of each size were reconstituted in Water for Injection, pooled into a 50 mL volume (100, 200, or 400 IU/mL for the 250, 500, and 1000 IU vial sizes, respectively), and aseptically transferred to pump reservoirs. Two mini-pumps were evaluated (WalkMed 350 Ambulatory Infusion Pump and CADD-Legacy PLUS Ambulatory Infusion Pump Model 6500) using a flow rate of 0.6 mL/hr. Reservoir bags containing reconstituted rFVIII-FS, pumps, and tubing were incubated at 30°C and samples were withdrawn to test coagulation activity via one-stage and chromogenic assays after 0.5, 1, 2, 3, 6, 12, 24, and 48 hours. Sample remaining in the reservoir after 48 hours was tested for sterility. The reservoirs and tubing used in this study were made from polyvinyl chloride (PVC), which has a high FVIII adsorption potential. Results for all 1000 IU lots based on the recoveries obtained at the first time point demonstrated >80% activity at the end of the study using both the one-stage and chromogenic assays on both pumps. Results for all 500 IU lots showed similar recoveries (≥80%) for both pumps at study end using the chromogenic assay. However, the one-stage assay gave higher recovery values for the WalkMed pump (>90%) compared to the CADD pump (>75%). Results for all 250 IU lots demonstrated ≥79% activity at the end of the study using both pumps and both assays. All lots passed the sterility test. These findings indicate that rFVIII-FS is stable in both the WalkMed and CADD pumps and that sterility of rFVIII-FS is maintained for at least 48 hours. This suggests that rFVIII-FS is suitable for use in continuous infusion.

1990 ◽  
Vol 64 (02) ◽  
pp. 251-255 ◽  
Author(s):  
Claudine Mazurier ◽  
Armelle Parquet-Gernez ◽  
Maurice Goudemand

SummaryThe assessment of factor VIII coagulant activity (FVTII: C) in recently available highly purified and concentrated FVTII therapeutic products calls for careful evaluation of assay methodologies. We assayed more than 130 batches of a concentrate with a specific activity of about 150 FVTII :C units/mg protein, using one-stage and two-stage clotting and chromogenic methods. There was good agreement between the potency estimates obtained with the different methods. We also compared the FVTII :C potencies obtained after predilution in buffer or FVIII-deficient plasma using either calibrated plasma or FVTII concentrate as references. With the one-stage assay we found a marked discrepancy between the potency values obtained with buffer and with FVTII-deficient plasma used as prediluents. In order to validate our “in vitro” data we performed 6 “in vivo” analyses in severe haemophilia A patients. On the basis of the overall data obtained we chose to label FVIII potency by using FVIII-deficient plasma as prediluent, reference plasma as standard and the chromogenic assay method.


2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Tarek M. Owaidah ◽  
Hazzaa A. Alzahrani ◽  
Nouf S. Al-Numair ◽  
Abdulmjeed O. Alnosair ◽  
Amelita M. Aguilos ◽  
...  

Background. The one-stage assay is the most common method to measure factor VIII activity (FVIII : C) in hemophilia A patients. The chromogenic assay is another two-stage test involving purified coagulation factors followed by factor Xa-specific chromogenic substrate. Aim. This study aimed to assess the discrepancy and correlation between the chromogenic and one-stage assays in measuring FVIII : C levels in hemophilia patients receiving Extended Half-Life Elocta® as a recombinant extended half-life coagulation factor. Methods. We performed a study comparing the measurements of FVIII : C levels by the chromogenic versus the one-stage assays at different drug levels. Data of FVIII : C levels, dosage, and the time interval from administration to measurement were retrieved from the hospital records. The correlation, mean differences, and discrepancy between the two assays were calculated. The linear regression analysis was used to predict the time interval till reaching 1% FVIII : C. Results. Fourteen patients with 56 samples were included in the study. Of them, 13 patients were receiving Elocta® as a prophylactic, while one was receiving Elocta® on demand. One-third of these samples showed a discrepancy between the chromogenic and one-stage assays. The two assays were well correlated. Mean differences were significant at the individual and the time interval level. The time since the last Elocta® injection could significantly predict FVIII : C levels (β = 0.366, P<0.001). Conclusion. Our findings suggested a significant difference between both methods; the FVIII : C levels measured by the one-stage assay were less than those estimated by the chromogenic assay. However, the measurements of FVIII levels by the two assays were well correlated but discrepant in one-third of the samples. The levels of FVIII : C reach 1% after 5.4 days since the last Elocta® administration.


Haemophilia ◽  
2020 ◽  
Vol 26 (5) ◽  
pp. 916-922
Author(s):  
Lisette M. Schütte ◽  
Luca S. Hodes ◽  
Iris Moort ◽  
Sara C. M. Stoof ◽  
Frank W. G. Leebeek ◽  
...  

1996 ◽  
Vol 76 (06) ◽  
pp. 0950-0956 ◽  
Author(s):  
Christine Lee ◽  
Trevor Barrowcliffe ◽  
Gordon Bray ◽  
Ed Gomperts ◽  
Anthony Hubbard ◽  
...  

SummaryIn a study to demonstrate the safety and pharmacokinetics (half-life and recovery) of two different method M purified AHF (Hemofil-M) concentrates processed in the USA and Spain, two different methods of factor VIII assay (one-stage clotting and chromogenic) have been compared in vivo. The study was a single centre blinded, randomised, crossover study. Twelve patients with severe haemophilia A (VIII: C <2 u/dl) were divided into two subgroups of six. None had received factor VIII concentrate within 48 h preceding the study. Twenty-four pharmacokinetic studies were performed in the 12 patients. Each subgroup received two different lots of study material (US and Spanish) at a dose of 50 u/kg seven days apart. A second randomisation was nominal potency, high: 1000 u or mid: 500 u per vial. The potency label was a one-stage clotting assay using the mega I standard. A standard pharmacokinetic study was performed over 24 h and each blinded sample was analysed in duplicate by a one-stage clotting (aPTT) and a chromogenic (Chromogenix AB; CS) assay at the Royal Free and NIBSC. Pharmacokinetic modelling was performed. The mean label for Hemofil-M using the chromogenic substrate assay was 79% that using the one stage assay (Mega I standard). The recovery was 17-28% higher measured by chromogenic compared to the clotting assay. Since most clinicians use the clotting assay, potency labelling using the chromogenic assay, will overestimate predicted Hemofil-M recovery by as much as 25%.


1979 ◽  
Vol 42 (04) ◽  
pp. 1230-1239 ◽  
Author(s):  
I M Nilsson ◽  
T B L Kirkwood ◽  
T W Barrowcliffe

SummaryThe recovery and half-life of VIII: C in the plasma of severely haemophilic patients was measured by one-stage and two-stage assays after injection of two Factor VIII concentrates (Hemofil, Hyland and Fraction I-O, Kabi). Plasma volumes were measured with an Evans� Blue technique, and both concentrates and post-infusion samples were measured against the same plasma standard.There was a highly significant difference in recoveries estimated by the two assay methods. The one-stage assays gave the most consistent results, in that the average recovery was 100%, whereas the two-stage assays gave only about 80% of the value expected from in vitro assays. There was no difference in recoveries between the two concentrates.The two-stage assays gave a slightly shorter half-life than the one-stage assays, and the half-life of Hemofil was also shorter than that of Fraction I-O.


Author(s):  
C K Kasper

Plasma factor VIII recoveries after infusions of factor VIII concentrates into patients with classic hemophilia have been measured in this laboratory for 14 years. Recently, we observed a decline in the in vivo recovery of factor VIII per factor VIII unit infused. In 1980, plasma factor VIII levels were measured by a one-stage APTT-based assay before and 10 min after 150 infusions of 46 lots of 3 brands of factor VIII concentrate produced in the U.S.A. Our pooled normal plasma reference was calibrated against WHO International Standard 2 and results expressed in International factor VIII units. Observed in vivo factor VIII recovery was compared to the value expected from calculations based on the unitage stated on the label. The ratio of observed/expected recovery averaged 56% per lot for brand A, 60% per lot for brand B, and 103% per lot for brand C. In vitro assays were performed on 22 lots on 36 occasions, and the ratio of observed/labelled units average 46% per lot for brand A, 53% for brand B and 75% for brand C. The two-stage factor VIII assay method of Pool and Robinson was also used to assay plasma samples from 18 infusions, and results averaged 135% of the one-stage values for infusions of brand A, 160% for brand B, and 109% for brand C. (Brand A is assayed by the manufacturer by a two-stage method, brands B and C by one-stage methods.)Decreased clinical efficacy was observed when postinfusion plasma factor VIII levels were lower than customary. The decline in potency of brands A and B has necessitated more frequent assay of patients and use of larger amounts of concentrate, with greatly-increased expense. Investigation of the effect of different assay methods and different factor VIII standards and references on the apparent factor VIII content of concentrates has begun.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3969-3969
Author(s):  
Donna M.M. Woloschuk ◽  
Jennifer M. Dyck ◽  
Sara J. Israels ◽  
Peter Toogood

Abstract Continuous infusion (CI) factor VIII (FVIII) replacement is commonly used for serious bleeds in patients with FVIII deficiency. Clinicians lack stability information for Refacto®, a B-domain deleted recombinant FVIII (BDDrFVIII), when it is diluted or stored in CI devices for extended time periods. We studied BDDrFVIII to determine its concentration- and time-dependent stability and sterility when stored (reconstituted; reconstituted then diluted with normal saline) at ambient temperature in syringe-based CI devices (CADD-MicroTM; Baxter ColleagueTM). Three replicates of BDDrFVIII 125unit/mL and 25unit/mL admixtures were admixed aseptically then placed in CI devices that operated continuously for 48 hours. Samples (0.5ml) were obtained from control solutions (stored in the manufacturer’s glass vial) or expressed from the distal end of tubing at Hour −0.25 (priming volume), 0, 1, 2, 4, 8, 12, 24 and 48. Samples were stored at −70C until assayed for Factor VIII activity using a 1-stage automated assay and Refacto® [chromogenic equivalent] Standard. Results of FVIII assays for each trio of replicates were averaged. BDDrFVIII admixtures were considered stable if they retained ≥80% baseline (control) FVIII values. Recoveries for BDDrFVIII 125unit/mL admixtures remained stable and sterile for 48 hours when stored in the manufacturer’s glass vial, Baxter ColleagueTM or CADD MicroTM devices, sufficient for clinical use (Table). BDDrFVIII, when diluted to 25unit/mL, remained sterile but not stable when stored in Baxter ColleagueTM or CADD MicroTM devices, and is not recommended for CI in clinical settings. Loss of FVIII activity in BDDrFVIII 25unit/mL admixtures is thought to be due to binding of BDDrFVIII to device components. %FVIII Activity of BDDrFVIII Stored in Infusion Devices Hr 0 Hr 1 Hr 2 Hr 4 Hr 12 Hr 24 Hr 48 Mfr Glass Vial (Control) 92.5 93 90.7 90.8 93.2 76 80.7 CADD-Micro 125unit/ml 80 84 86.3 78.3 86.3 80 81.7 Baxter Colleague 125unit/ml 86.3 79 74 85 77.7 81 82.3 CADD-Micro 25unit/ml 65.7 61.3 56.3 59 57.5 59.7 56.3 Baxter Colleague 25unit/ml 18.7 19.3 33 24.3 27 27 27.3


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3539-3539
Author(s):  
Monika Maas Enriquez ◽  
Horst Beckmann ◽  
Yvonne Katterle ◽  
Stefan Bruns ◽  
Despina Tseneklidou-Stoeter ◽  
...  

Abstract Background: BAY 81-8973 is a full-length unmodified recombinant factor VIII (rFVIII) in development for the treatment of hemophilia A. BAY 81-8973 has the same amino acid sequence as Bayer's sucrose-formulated rFVIII but is manufactured using the latest technologies. Potency labeling is based on the chromogenic assay. BAY 81-8973 has demonstrated an excellent safety and efficacy profile in the clinical development program. This field study was conducted to evaluate assay variability in BAY 81-8973 measurements compared with a marketed rFVIII (Advate®, Baxter, Westlake Village, CA) using the methods, reference standards, and reagents typically used in clinical laboratories. Methods: Clinical laboratories in North America, Europe, Israel, and South Africa were invited to participate in the study. Each laboratory was provided with 21 blinded samples to analyze using their routine assay (one-stage, chromogenic, or both), reagents, and standards. The 21 samples consisted of 3 aliquots each of spiked hemophilia plasma containing normal von Willebrand factor levels with BAY 81-8973 at 3 different levels: <10 IU/dL (low), 10-50 IU/dL (medium), >50 IU/dL (high); 3 aliquots each of spiked hemophilia plasma with Advate at the same levels (low, medium, high); and 3 aliquots of commercially available positive control sample (normal human plasma). Samples were identified by unique numbers and by target FVIII levels (low, medium, high). The nominal spiked target levels of FVIII concentration were 0.043 IU/mL (low), 0.375 IU/mL (medium), and 0.865 IU/mL (high) for BAY 81-8973 and Advate and 0.960 IU/mL for the plasma control. Results were analyzed statistically for intra- and interlaboratory variability. Results: Of 82 laboratories contacted, 41 in 11 countries participated. Thirty-one laboratories used the one-stage assay only, 1 used the chromogenic assay only, and 9 used both assays. Intralaboratory variability was <11% for both assays at all FVIII levels and was similar for BAY 81-8973, Advate, and the plasma control. Interlaboratory variability was highest for the lowest concentration using the chromogenic assay (percent coefficient of variation: 60% for BAY 81-8973, 51% for Advate) and decreased to 14% for BAY 81-8973 (Advate, 12%; plasma control, 10%) with the one-stage assay and 5% (Advate, 6%; plasma control, 7%) with the chromogenic assay at the highest concentration. For the 9 laboratories that used both the one-stage and chromogenic assays, the chromogenic:one-stage ratio for mean values for BAY 81-8973 at low, medium, and high concentrations was 1.04, 1.04, and 1.14, respectively; for Advate, the ratios were 1.02, 1.07, and 1.21. Conclusions: The laboratories participating in this field study used a wide range of methods and reagents for FVIII measurements. The variability of the results was similar for both BAY 81-8973 and Advate and highest for low concentrations. There was no relevant difference in the results between the one-stage and chromogenic assays. Disclosures Maas Enriquez: Bayer Pharma AG: Employment. Beckmann:Bayer Pharma AG: Employment. Katterle:Bayer Pharma AG: Employment. Bruns:Winicker Norimed: Employment. Tseneklidou-Stoeter:Bayer Pharma AG: Employment. Kitchen:Bayer Pharma AG: Other: Advisory fees, Speakers Bureau.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5043-5043
Author(s):  
John M. Teare ◽  
Jared Trefethen ◽  
Stephen Garger ◽  
Prasad Mathew

Abstract Continuous infusion (CI) is used in many treatment centers as an option at the time when patients with hemophilia A undergo major surgical procedures. Benefits of CI versus bolus infusion (BI) of factor VIII (FVIII) in patients undergoing surgery include avoiding unnecessarily high peaks and low troughs of FVIII levels and reducing FVIII consumption during and after surgery, partially due to decreased clearance. Stability and long-term potency of FVIII products under CI conditions have been shown to exhibit variability. Thus, it is important to demonstrate stability for each product used in CI applications. BAY 81-8973 (Kovaltry®, Bayer, Berkeley, CA) is an unmodified, full-length recombinant human FVIII product with a primary amino acid sequence identical to that of sucrose-formulated recombinant FVIII (rFVIII-FS; Kogenate® FS, Bayer). rFVIII-FS was shown previously to be stable in solution for up to 7 days, to be safe and effective for CI during surgery, and to be suitable for pediatric and adult patients. The present study investigated whether BAY 81-8973 has adequate potency and purity up to 24 hours after reconstitution, which may indicate suitability for CI applications. BAY 81-8973 drug product in 250-IU and 500-IU vial sizes was tested 0, 4, 8, 12, and 24 hours after reconstitution with sterile water for injection and storage at room temperature in 30-mL polypropylene syringes (BD Plastipak™, BD, Franklin Lakes, NJ). The drug product was tested for potency (chromogenic assay), purity (high performance liquid chromatography - size exclusion chromatography [HPLC-SEC]), total protein content, pH, solution clarity, and subvisible particulates (high accuracy liquid particle counting - subvisible particles [HIAC-SVP]). There were no changes in potency, pH, clarity, aggregation, chain dissociation, subvisible particles, or total protein with either 250- or 500-IU BAY 81-8973 for up to 24 hours. Results were also consistent with the demonstrated safety and efficacy of rFVIII-FS for CI during surgery. These data indicate that BAY 81-8973 may be suitable for CI applications for up to 24 hours. Disclosures Teare: Bayer: Employment. Trefethen:Bayer: Employment. Garger:Bayer: Employment. Mathew:Bayer: Employment.


Author(s):  
T W Barrowcliffe ◽  
E Gray ◽  
G Kemball-Cook

The activities of an activated Factor IX concentrate (FEIBA, Immuno AG) were studied by two in vitro assays: a one-stage method using VUI-deficient plasma as substrate, and a two-stage assay based on the thrombin generation test. The nature of the active principle was explored by measuring the reduction in activity when FEIBA was incubated with specific antibodies.Incubation of FEIBA with human antibodies to Factor VIII reduced its activity by about 30% in the one-stage assay, and about 50% in the two-stage assay, suggesting that FEIBA contains Factor VIII procoagulant activity. Inactivation of the Factor VIII in FEIBA was somewhat slower than that of normal Factor VIII, indicating partial protection from inhibition. Human antibodies to Factor IX inhibited the one stage activity by about 30%, and incubation with both antibodies also produced a 30% reduction in activity. The remaining procoagulant activity decayed only slowly when incubated with non-inhibitor plasma. In contrast, purified human Factor Xa lost activity rapidly on incubation in normal plasma, as did a purified fraction from a Factor IX concentrate, which had high activity in the one-stage assay.These results suggest that the in vitro activity of FEIBA is due to at least two components. One component appears to be dependent on both Factors VIII and IX and may be a complex of VIII and IXa. The other component acts later than Factors VIII and IX in the coagulation cascade but, unlike purified Factor Xa, is relatively resistant to inactivation by plasma inhibitors such as antithrombin III. FEIBA was also found to contain phospholipid, and it may be that the phospholipid protects both the Factor VIII and activated enzymes from their inhibitors.


Sign in / Sign up

Export Citation Format

Share Document