Semin Thromb Hemost
DOI: 10.1055/s-0044-1785483
Review Article

Gene Therapy in Hemophilia A: Achievements, Challenges, and Perspectives

Natasha S. Bala
1   Rady Children's Hospital San Diego, Hemophilia and Thrombosis Treatment Center, San Diego, California
2   Department of Pediatrics, UC San Diego School of Medicine, La Jolla, California
,
Courtney D. Thornburg
1   Rady Children's Hospital San Diego, Hemophilia and Thrombosis Treatment Center, San Diego, California
2   Department of Pediatrics, UC San Diego School of Medicine, La Jolla, California
› Author Affiliations

Abstract

Strides in advancements of care of persons with hemophilia include development of long-acting factor replacement therapies, novel substitution and hemostatic rebalancing agents, and most recently approved gene therapy. Several decades of preclinical and clinical trials have led to development of adeno-associated viral (AAV) vector-mediated gene transfer for endogenous production of factor VIII (FVIII) in hemophilia A (HA). Only one gene therapy product for HA (valoctocogene roxaparvovec) has been approved by regulatory authorities. Results of valoctocogene roxaparvovec trial show significant improvement in bleeding rates and use of factor replacement therapy; however, sustainability and duration of response show variability with overall decline in FVIII expression over time. Further challenges include untoward adverse effects involving liver toxicity requiring immunosuppression and development of neutralizing antibodies to AAV vector rendering future doses ineffective. Real-life applicability of gene therapy for HA will require appropriate patient screening, infrastructure setup, long-term monitoring including data collection of patient-reported outcomes and innovative payment schemes. This review article highlights the success and development of HA gene therapy trials, challenges including adverse outcomes and variability of response, and perspectives on approach to gene therapy including shared decision-making and need for future strategies to overcome the several unmet needs.



Publication History

Article published online:
08 April 2024

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