An Observational Study Called JOIHA to Learn More About How Well the Treatment With Jivi Works to Prevent Problems With Joints in Adults With Hemophilia A.

This is an observational study in which data from people with hemophilia A who decide on their own or by recommendation of their doctors to take Jivi are collected and studied. In observational studies, only observations are made without specified advice or interventions.

Hemophilia A is a genetic bleeding disorder that is caused by the lack of a protein in the blood called "clotting factor 8" (FVIII). FVIII is naturally found in the blood where it causes the blood to clump together to help prevent and stop bleeding. People with lower levels of FVIII or with FVIII that does not work properly may bleed for a long time from minor wounds, have painful bleeding into joints, or have internal bleeding.

The study treatment, Jivi (also called damoctocog alfa pegol), is already available for doctors to prescribe to people with hemophilia A to treat and prevent bleeding. It works by replacing the missing FVIII, or the FVIII that does not work properly.

People with hemophilia A need frequent injections of FVIII products into the vein. So called standard half-life (SHL) products need to be given 2 to 4 times a week for the prevention of bleeding. In recent years, new products like Jivi called extended half-life (EHL) products have available. These products last longer in the body so that they require to be given less often with injections up to every 7 days. Thus, these treatments may be easier and more comfortable to stick to in daily life. There is no general plan concerning the best amount of treatment and the frequency of injections for the prevention of bleeding, since the severity may be different and individual risk factors have to be considered. Doctors often decide on a treatment plan based on patient's disease and response.

Clinical studies have already shown that people with hemophilia A benefit from the treatment with Jivi. However, there are no data available coming from the real-world about how well Jivi works to support joint health, measured by ultrasound (US) examination and HEAD-US score.

In this study, researchers want to learn more about how well Jivi works if used for prolonged periods of treatment under real-world settings to prevent problems with joints in people with hemophilia A. How well it works means to find out if participants' joints status can be improved by treatment with Jivi.

To do this, researchers will collect data about participants' joints status by

* making images of participants' joints by using sound waves (ultrasound), and * using HEAD-US score after 24 months of treatment with Jivi. The researchers will then compare these data to the participants' joints status before treatment start with Jivi.

Besides this data collection, no further tests or examinations are planned in this study.

Some participants in this study will already be receiving treatment with Jivi as part of their regular care no more than 12 months. And some participants will start to take Jivi in this study as prescribed by their doctors during routine practice according to the approved product information.

The researchers will collect data from each patient for a period of 26 months after initiation of the Jivi treatment.

There are no required visits or tests in this study