Abstract
Summary: Background: The development of neutralizing antibodies, referred to as inhibitors, against factor VIII is a major complication associated with FVIII infusion therapy for the treatment of hemophilia A (HA). Previous studies have shown that a subset of HA patients and a low percentage of healthy individuals harbor non-neutralizing anti-FVIII antibodies that do not elicit the clinical manifestations associated with inhibitor development. Objective: To assess HA patients' anti-FVIII antibody profiles as potential predictors of clinical outcomes. Methods: A fluorescence immunoassay (FLI) was used to detect anti-FVIII antibodies in 491 samples from 371 HA patients. Results: Assessments of antibody profiles showed that the presence of anti-FVIII IgG1, IgG2 or IgG4 correlated qualitatively and quantitatively with the presence of an FVIII inhibitor as determined with the Nijmegen-Bethesda assay (NBA). Forty-eight patients with a negative inhibitor history contributed serial samples to the study, including seven patients who had negative NBA titers initially and later converted to being NBA-positive. The FLI detected anti-FVIII IgG1 in five of those seven patients prior to their conversion to NBA-positive. Five of 15 serial-sample patients who had a negative inhibitor history and had anti-FVIII IgG1 later developed an inhibitor, as compared with two of 33 patients with a negative inhibitor history without anti-FVIII IgG1. Conclusions: These data provide a rationale for future studies designed both to monitor the dynamics of anti-FVIII antibody profiles in HA patients as a potential predictor of future inhibitor development and to assess the value of the anti-FVIII FLI as a supplement to traditional inhibitor testing.
Original language | English (US) |
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Pages (from-to) | 47-53 |
Number of pages | 7 |
Journal | Journal of Thrombosis and Haemostasis |
Volume | 13 |
Issue number | 1 |
DOIs | |
State | Published - Jan 1 2015 |
All Science Journal Classification (ASJC) codes
- Hematology