Eptacog α/factor VIII inhibitor bypassing fraction

2021 ◽  
Vol 1858 (1) ◽  
pp. 155-155
Keyword(s):  
Factor Viii ◽  
Factor Viii Inhibitor ◽  
Viii Inhibitor

Acquired Haemophilia: Functional Study of Antibodies to Factor VIII

1981 ◽  
Vol 45 (03) ◽  
pp. 285-289 ◽  
Author(s):  
J P Allain ◽  
A Gaillandre ◽  
D Frommel
Keyword(s):  
Factor Viii ◽  
Functional Study ◽  
Factor Viii Inhibitor ◽  
Acquired Haemophilia ◽  
Viii Inhibitor ◽  
Kinetics Of ◽  
Antibody Function ◽  
Native Plasma

SummaryFactor VIII complex and its interaction with antibodies to factor VIII have been studied in 17 non-haemophilic patients with factor VIII inhibitor. Low VIII:C and high VIIIR.Ag levels were found in all patients. VIII:WF levels were 50% of those of VTIIRrAg, possibly related to an increase of poorly aggregated and electrophoretically fast moving VIIIR:Ag oligomers.Antibody function has been characterized by kinetics of VIII :C inactivation, saturability by normal plasma and the slope of the affinity curve. Two major patterns were observed:1) Antibodies from 6 patients behaved similarly to those from haemophiliacs by showing second order inhibition kinetics, easy saturability and steep affinity slope (> 1).2) Antibodies from other patients, usually with lower titres, inactivated VIII :C according to complex order kinetics, were not saturable, and had a less steep affinity slope (< 0.7). In native plasma, or after mixing with factor VIII concentrate, antibodies of the second group did not form immune complexes with the whole factor VIII molecular complex. However, dissociation procedures did release some antibodies from apparently low molecular weight complexes formed in vivo or in vitro. For appropriate management of non-haemophilic patients with factor VIII inhibitor, it is important to determine the functional properties of their antibodies to factor VIII.

A Higher than Expected Incidence of Factor VIII Inhibitors in Multitransfused Haemophilia A Patients Treated with an Intermediate Purity Pasteurized Factor VIII Concentrate

1993 ◽  
Vol 69 (02) ◽  
pp. 115-118 ◽  
Author(s):  
Kathelijne Peerlinck ◽  
Jef Arnout ◽  
Jean Guy Gilles ◽  
Jean-Marie Saint-Remy ◽  
Jos Vermylen
Keyword(s):  
Factor Viii ◽  
Randomized Trials ◽  
Specific Factor ◽  
Factor Viii Inhibitor ◽  
Haemophilia A ◽  
Viral Inactivation ◽  
Gradual Decline ◽  
Inhibitor Level ◽  
Factor Viii Concentrates ◽  
Viii Inhibitor

SummaryIn May 1990, 218 patients with haemophilia A regularly attending the Leuven Haemophilia Center were randomly assigned to a group receiving either of two newly introduced factor VIII concentrates: factor VIII-P, an intermediate purity pasteurized concentrate, or factor VIII-SD, a high purity concentrate treated with solvent-detergent for viral inactivation.Patients were followed from May 1990 until October 1991. Between August 1991 and October 1991 a clinically important factor VIII inhibitor was detected in five out of the 109 patients receiving factor VIII-P while none of the 109 patients receiving factor VIII-SD developed such antibodies. All patients acquiring an inhibitor had previously been clinically tolerant to transfused factor VIII with 200 to more than 1,000 days of exposure to factor VIII prior to May 1990. Patients with inhibitors were transfused daily with 30 U factor VIII-SD per kg body weight, which was associated with a gradual decline of the inhibitor level. In all patients the antibodies were relatively slow-acting and predominantly directed towards the light chain of factor VIII.This study demonstrates a higher than expected incidence of factor VIII inhibitors associated with the use of a specific factor VIII concentrate in multitransfused haemophilia A patients. It indicates the usefulness of evaluating newly introduced concentrates in prospective, randomized trials.

In Vitro Thrombogenicity Tests of Factor IX Concentrates

1979 ◽  
Vol 42 (05) ◽  
pp. 1355-1367 ◽  
Author(s):  
C V Prowse ◽  
A Chirnside ◽  
R A Elton
Keyword(s):  
Factor Viii ◽  
Partial Thromboplastin Time ◽  
Generation Time ◽  
Activated Partial Thromboplastin Time ◽  
Factor Ix ◽  
In Vitro Tests ◽  
Factor Viii Inhibitor ◽  
Factor Ixa ◽  
Viii Inhibitor

SummaryVarious factor IX concentrates have been examined in a number of in vitro tests of thrombogenicity. The results suggest that some tests are superfluous as in concentrates with activity in any of these tests activation is revealed by a combination of the non-activated partial thromboplastin time, the thrombin (or Xa) generation time and factor VIII inhibitor bypassing activity tests. Assay of individual coagulant enzymes revealed that most concentrates contained more factor IXa than Xa. However only a small number of concentrates, chiefly those that had been purposefully activated, contained appreciable amounts of either enzyme.

Pemphigus Vulgaris Associated with Acquired Hemophilia due to Factor VIII Inhibitor

2003 ◽  
Vol 65 (3) ◽  
pp. 223-226 ◽  
Author(s):  
Masahide YAMAGUCHI ◽  
Mamoru KOHDA ◽  
Hiroaki UEKI ◽  
Wataru FUJIMOTO
Keyword(s):  
Factor Viii ◽  
Pemphigus Vulgaris ◽  
Factor Viii Inhibitor ◽  
Acquired Hemophilia ◽  
Viii Inhibitor

Factor-VIII Inhibitor in Less Severely Affected Haemophilic Patients

1975 ◽  
Author(s):  
E. G. D. Tuddenham ◽  
A. L. Bloom ◽  
J. C. Giddings ◽  
C. A. Barrett
Keyword(s):  
Factor Viii ◽  
Factor Viii Inhibitor ◽  
Factor Viii Level ◽  
Replacement Treatment ◽  
Viii Level ◽  
Viii Inhibitor ◽  
In Vivo Recovery ◽  
Better Than

The occurrence of factor VIII inhibitor in five mild or moderately affected liaemophilic patients is described. In four patients the inhibitor inactivated endogenous factor VIII an dtemporarily converted them to severely affected haemophiliacs with factor VIII level of 0%. In the fifth patient, a brother of one of the others, the inhibitor although more potent did not inactivate the patient’s own factor VIII and did not completely inactivate normal factor VIII in vitro. This patient responded to treatment with factor-VIII concentrate but the in-vivo recovery was reduced. The patient’s plasma was tested against a panel of normal donors but it inactivated factor VIII in each to a similar extent and no evidence for normal factor-VIII groups was obtained. In the other patients the response to replacement treatment was also better than that usually seen in severely affected haemophilic patients with inhibitor. In the two related patients the inhibitors have so far persisted but in the unrelated patients the inhibitors eventually disappeared and did not always recur with subsequent therapy. The incidence of factor- VIII inhibitor in less severe haemophiliacs (factor VIII > 3% ) in this centre is 6% suggesting that the complication is more frequent in this type of patient than hitherto recognised.

scholarly journals A Clinical and Experimental Study of Acquired Inhibitors to Factor VIII

Blood ◽  
1965 ◽  
Vol 26 (6) ◽  
pp. 805-818 ◽  
Author(s):  
HAROLD R. ROBERTS ◽  
MARGARET B. SCALES ◽  
JOHN T. MADISON ◽  
WILLIAM P. WEBSTER ◽  
GEORGE D. PENICK
Keyword(s):  
Experimental Study ◽  
Factor Viii ◽  
Mode Of Action ◽  
Exchange Transfusion ◽  
Hemophilia A ◽  
Retroperitoneal Hematoma ◽  
Factor Viii Inhibitor ◽  
Viii Inhibitor ◽  
Potent Factor

Abstract Factor VIII inhibitors which developed in four patients with hemophilia A are described. These inhibitors are apparently specific for Factor VIII and are capable of inducing a transient hemophilic state when injected into dogs. The genesis, properties, and mode of action of these inhibitors can be explained on an immunologic basis and it seems most likely that they represent an antibody to Factor VIII. One hemophilia A patient, with retroperitoneal hematoma and a potent Factor VIII inhibitor, was successfully treated by an exchange transfusion followed by administration of purified porcine Factor VIII.

Normal pregnancy in a patient with a postpartum factor VIII inhibitor

1987 ◽  
Vol 24 (1) ◽  
pp. 107-109 ◽  
Author(s):  
V. Vicente ◽  
I. Alberca ◽  
R. Gonzalez ◽  
A. Alegre
Keyword(s):  
Factor Viii ◽  
Normal Pregnancy ◽  
Factor Viii Inhibitor ◽  
Viii Inhibitor

New Method for Quantifying Lupus Anticoagulant

1996 ◽  
Vol 2 (4) ◽  
pp. 237-240
Author(s):  
Roy Speck
Keyword(s):  
Factor Viii ◽  
Confidence Level ◽  
Lupus Anticoagulant ◽  
Heparin Therapy ◽  
Factor Ix ◽  
New Method ◽  
Factor Viii Inhibitor ◽  
Single Factor ◽  
Viii Inhibitor

A method is presented using a new reagent containing propylgallate for the quantitative determina tion of lupus anticoagulant. The amount of an optimized phospholipid standard required by the clotting reaction was found to be 32-50 μg/ml at a 95% confidence level, with a mean of 41 μg/ml. This method eliminates the ef fect of heparin therapy, coumadin therapy, factor-VIII inhibitor, factor-IX inhibitor, and single-factor deficien cies that afflict presently used lupus anticoagulant screen ing and confirmatory procedures. Using this method, it should be possible to detect lupus anticoagulant in pa tients at a much lower level and follow the effect of ther apy on lupus anticoagulant.

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