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Carefully controlled schedules. Undercurrents of uncertainty. Persistent pain. People who are living with hemophilia B, and those who love them, face a lifetime of managing the complexities of this condition.

While significant advancements have been made in the treatment of hemophilia B, there is still a desire for new treatment options to address unmet needs for people with moderate to severe forms of the condition.

Many have heard of hemophilia B – a rare genetic, bleeding disorder. Aside from a cursory familiarity with the condition, few understand the seriousness of the disease and the burden it places on the lives of approximately 6,000 people in the U.S., two thirds of whom have moderate to severe hemophilia B. While many manage the condition with factor IX (FIX) replacement therapy, which temporarily replaces or supplements low levels of factor IX, a protein that helps blood to clot, they must adhere to strictly scheduled, life-long infusions and may still experience spontaneous bleeding episodes which could require additional infusions. People with hemophilia B are also more vulnerable to traumatic bleeding into their muscles and joints which often results in limited mobility, joint damage, and severe pain.

People with hemophilia B have an inherited defect in one of their genes, which causes low levels of an important protein, factor IX, that helps their blood clot. Activities that seem easy to some can be a real struggle or near impossibility for a person with hemophilia B.

Beyond the physical challenges, a person living with hemophilia B must balance the mental, social, and emotional impacts of their condition. Depression and anxiety can be a significant factor. Anyone who has experienced the cloud of depression or pull of anxiety can appreciate the intense challenge of managing their mental health while also navigating infusion schedules, life, work, and family. The effects of hemophilia B can also ripple to friends, family, and caregivers. This can ultimately result in increased cost to the broader healthcare system as mental health impacts can lead to poor adherence to treatment plans which may increase bleeding episodes.

Overall healthcare costs can be 25 times higher for a person living with moderate to severe hemophilia B – amounting to a total adult life time cost of more than $20 million per person.

“Hemophilia B is a promising target for gene therapy because it is caused by a single gene mutation.”

Due to ongoing research in the field of gene therapy, many are optimistic that long-term disease control could be possible through a single infusion for people with moderate to severe forms of hemophilia B. Hemophilia B is a promising target for gene therapy because it is caused by a single gene mutation. Further, the gene that causes hemophilia B is both small in size and structurally simpler in comparison to other bleeding disorders, such as hemophilia A. The goal of investigational gene therapy for hemophilia B is to reduce or eliminate the need for regular infusions by addressing the underlying genetic cause of the condition. By introducing a functional, working gene into the liver, a person with hemophilia B could start creating their own stable and protective level of factor IX without the need for prophylactic infusions.

While gene therapy is not yet a reality, pursuing continued innovation is a critical next step in the evolution of hemophilia B care.

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