Occurrence of FVIII Inhibitors in Hemophilia A Patients Following an Institutional Switch to a Third Generation B-Domain-Deleted FVIII

Louise H. Hooimeijer, Marjet A. Stein-Wit, Marja A.J. Voskuilen, Michaël V. Lukens, Karina Meijer, Anja B.U. Mäkelburg, Rienk Y.J. Tamminga*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

1 Citation (Scopus)
43 Downloads (Pure)

Abstract

In 2018, Refacto AFR, a B-domain-deleted third-generation FVIII concentrate, became our preferential product. After the introduction, the development of inhibitors was prospectively monitored; retrospectively, we sought for risk factors in the patients who developed a de-novo inhibitor. Over a period of 15 months, 4/19 adult patients with non-severe haemophilia who were treated on demand for surgery, developed high titer antibodies to FVIII after administration of Refacto AFR; 5/52 mostly severe patients on prophylaxis, developed an inhibitor (3 ≥ 0.1 BU; 1 > 0.6 BU, 1 high titre) after they switched to Refacto AFR; all were children <14 years of age and with >100 exposure days, none related to surgery or intensive treatment; all received KovaltryR before. In conclusion: inhibitors were encountered in on demand patients and previously treated prophylaxis patients; this observation might be a coincidental finding, but also risk factors like genotype and surgery and/or that Refacto AFR is more immunogenic should be considered. For the patients on prophylaxis we hypothesize that loss of tolerance by preceding KovaltryR might have contributed to inhibitor development.

Original languageEnglish
Number of pages5
JournalClinical and Applied Thrombosis/Hemostasis
Volume29
DOIs
Publication statusPublished - Jan-2023

Keywords

  • antibodies
  • factor VIII concentrate
  • hemophilia A
  • immunity
  • therapeutics

Fingerprint

Dive into the research topics of 'Occurrence of FVIII Inhibitors in Hemophilia A Patients Following an Institutional Switch to a Third Generation B-Domain-Deleted FVIII'. Together they form a unique fingerprint.

Cite this