This study is for people with haemophilia, which is a condition where blood doesn't clot properly, leading to excessive bleeding. It focuses on a new medicine called concizumab. The goal is to see if concizumab can help prevent bleeding and is safe to use.

Participants will need to inject themselves every day with a special pen. This study lasts between 2 to 4 years, depending on when the medicine becomes available in their country.

Eligibility criteria include having haemophilia A or B (severe or moderate), with or without inhibitors, and being male. Some may need to have previous treatment experience. Those with allergies to the medicine, or certain other health conditions, cannot join.

• **Study Duration**: Between 2 to 4 years.
• **Daily Commitment**: Daily self-injection with a pen.
• **Eligibility**: Must have haemophilia A or B and meet certain health criteria.