This clinical trial is focused on studying the long-term safety and effectiveness of a treatment for Hemophilia B, a genetic disorder that affects the blood’s ability to clot properly. The treatment being studied is called Etranacogene Dezaparvovec, also known by its code name CSL222. This treatment is a type of gene therapy, which involves using a specially designed virus to deliver a healthy version of a gene to the liver, where it can help produce a protein called Factor IX that is essential for blood clotting.
The purpose of this study is to monitor adult male participants who have previously received the CSL222 treatment in earlier studies. Participants will be followed over a long period to observe any potential side effects and to assess how well the treatment continues to work in reducing bleeding episodes. The study will also look at the participants’ quality of life and their need for additional treatments to manage their condition.
Throughout the study, participants will have regular check-ups to track their health and any changes in their condition. The study aims to provide valuable information on the long-term benefits and safety of Etranacogene Dezaparvovec for individuals with Hemophilia B, helping to improve future treatment options for this condition.



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