Abstract
Hemophilia B（HB）is an X-chromosome-linked recessive disorder caused by mutations in the gene encoding coagulation factor Ⅸ（FⅨ）, resulting in coagulation factor Ⅸ deficiency. However, factor replacement treatment, as the standard of care in patients with HB at present, still faces many challenges such as the need for lifelong medication, frequent venipunctures, fluctuation of FⅨ activity levels after infusion, and potential risk for the development of inhibitors. Gene therapy（GT）is an approach to achieve therapeutic goals by modifying or manipulating the expression of target genes and altering the biological properties of living cells. As favorable efficacy and safety are demonstrated in various clinical trials, some GT products for HB have been successfully marketed, and the clinical treatment landscape of HB is facing important changes. This article summarizes the major advances in this field and discusses some noteworthy issues to provide references for relevant research and clinical practice.