Priyanka Raheja, MBBS, MD, Royal London Hospital, London, UK, talks on immune response monitoring in patients with hemophilia treated with gene therapy, emphasizing the importance of this practice to identify patients that need to be treated with steroids to avoid a loss in transgene expression. This interview took place at the 30th Congress of the International Society on Thrombosis and Haemostasis (ISTH) 2022 held in London, UK.