Product‐dependent anti‐factor VIII antibodies

摘要: Summary. The development of anti-factor (F)VIIIantibodies in haemophilia A (HA) subjects undergoingreplacement therapy has been well documented. Thecorrelation between antibody and theFVIII product used for replacement remains asubject discussion. aim this study was toevaluate the presence anti-FVIII antibodies towardsthree commercial rFVIII products 34 HA subjects’plasmas. Antibodies were quantitated by a MultiplexFluorescence Immunoassay. All plasmas containedanti-FVIII at variable concentrationsranging from 50 n M to 570 l . Eleven 20 HAsubjects treated with one (r)FVIII containedinhibitory (0.8-3584 BU). Theinhibitory titre molar concentrationsof total mildly correlated (r 2 = 0.6).Pronounced differences recognition withthe three observed. For thegroup Product ‘A’, towards thisproduct 2.4-fold higher than that observed withanother full-length rFVIII-containing (Product‘B’) almost four-fold measuredwith B domain-less (Product ‘C’).For group 14 FVIIIother only showed higherantibody when measured product. Ourdata suggest anti-FVIIIantibodies is biased fortreatment significant fraction antibodiesbind domain FVIII.Keywords: VIII antibodies, bethesda assay,factor inhibitors, factor products, A,immunoassay