TY - JOUR
T1 - The IgG-degrading enzyme, Imlifidase, restores the therapeutic activity of FVIII in inhibitor-positive hemophilia A mice
AU - Bou-Jaoudeh, Melissa
AU - Delignat, Sandrine
AU - Daventure, Victoria
AU - Astermark, Jan
AU - Lévesque, Hervé
AU - Dimitrov, Jordan D.
AU - Deligne, Claire
AU - Proulle, Valérie
AU - Lacroix-Desmazes, Sébastien
PY - 2023/5
Y1 - 2023/5
N2 - Neutralizing anti-factor VIII (FVIII) antibodies, known as FVIII inhibitors, represent a major drawback of replacement therapy in persons with congenital hemophilia A (PwHA), rendering further infusions of FVIII ineffective. FVIII inhibitors can also appear in non-hemophilic individuals causing acquired hemophilia A (AHA). The use of non-FVIII bypassing agents in cases of bleeds or surgery in inhibitor-positive patients is complicated by the lack of reliable biological monitoring and increased thrombotic risk. Imlifidase (IdeS) is an endopeptidase that degrades human immunoglobulin G (IgG); it was recently approved for hyperimmune patients undergoing renal transplants. Here we investigated the ability of IdeS to eliminate FVIII inhibitors in vitro and in a model of inhibitor-positive HA mice. IdeS cleaved anti-FVIII plasma IgG from PwHA and AHA patients, and hydrolyzed recombinant human anti-FVIII IgG independently from their subclass or specificity for the A2, A3, C1 or C2 domains of FVIII. In HA mice passively immunized with recombinant human anti-FVIII IgG, IdeS restored the hemostatic efficacy of FVIII, as evidenced by the correction of the bleeding tendency. Our results provide the proof of concept for the transient removal of FVIII inhibitors by IdeS, thereby opening a therapeutic window for efficient FVIII replacement therapy in inhibitor-positive patients.
AB - Neutralizing anti-factor VIII (FVIII) antibodies, known as FVIII inhibitors, represent a major drawback of replacement therapy in persons with congenital hemophilia A (PwHA), rendering further infusions of FVIII ineffective. FVIII inhibitors can also appear in non-hemophilic individuals causing acquired hemophilia A (AHA). The use of non-FVIII bypassing agents in cases of bleeds or surgery in inhibitor-positive patients is complicated by the lack of reliable biological monitoring and increased thrombotic risk. Imlifidase (IdeS) is an endopeptidase that degrades human immunoglobulin G (IgG); it was recently approved for hyperimmune patients undergoing renal transplants. Here we investigated the ability of IdeS to eliminate FVIII inhibitors in vitro and in a model of inhibitor-positive HA mice. IdeS cleaved anti-FVIII plasma IgG from PwHA and AHA patients, and hydrolyzed recombinant human anti-FVIII IgG independently from their subclass or specificity for the A2, A3, C1 or C2 domains of FVIII. In HA mice passively immunized with recombinant human anti-FVIII IgG, IdeS restored the hemostatic efficacy of FVIII, as evidenced by the correction of the bleeding tendency. Our results provide the proof of concept for the transient removal of FVIII inhibitors by IdeS, thereby opening a therapeutic window for efficient FVIII replacement therapy in inhibitor-positive patients.
U2 - 10.3324/haematol.2022.281895
DO - 10.3324/haematol.2022.281895
M3 - Article
C2 - 36655430
AN - SCOPUS:85158146311
SN - 0390-6078
VL - 108
SP - 1322
EP - 1334
JO - Haematologica
JF - Haematologica
IS - 5
ER -