This study is looking at how Mim8 works in people with haemophilia A, who either have inhibitors or do not have inhibitors. Mim8 is a new medicine that will be used to avoid bleeding episodes. Mim8 works by replacing the function of the missing clotting factor VIII (FVIII). The study will last for up to 5.5 years. The duration of the study depends on when the participant enrolled in this study. The study will end if Mim8 is approved and marketed in participant's country during the study, or the study will end in June 2028, whichever comes first. Participants will get up to 262 injections; the number of injections depends on how often participants will get injections and how long time participants take part in the study. While taking part in this study, there are some restrictions about what medicine participants can use. The study doctor will tell the participants more about this. In case the participants experience bleeds, these can be treated with additional haemostatic medicine as agreed with the study doctor. Female participants cannot take part if they are pregnant, breast-feeding or plan to get pregnant during the study period.