Novo Nordisk is developing the study medicine Mim8 for the treatment of haemophilia A. The study aims to show similar levels of Mim8 in blood when using a new pen injector, called DV3407-C1 pen injector, and when using a syringe and cartridge. The new pen injector is intended to facilitate the administration of Mim8 for patients with haemophilia A. The participants will get Mim8 as injection under the skin (subcutaneously) of the belly using the DV3407-C1 pen injector and a needle (hereinafter referred to as pen injector) or using a needle and syringe from a cartridge (hereafter called syringe and cartridge). The participants will receive one injection with Mim8, either with the DV3407-C1 pen injector or with a syringe and cartridge. The study participation will last up to 20 weeks. Only healthy men can take part in the study.

Inclusion Criteria:

• Male aged 18-55 years (both inclusive) at the time of signing informed consent.
• Body mass index (BMI) between 18.5 and 29.9 kilogram per square metre (kg/m^2) (both inclusive) at screening.
• Body weight between 60.0 and 100.0 kg (both inclusive) at screening.
• Considered to be generally healthy based on the medical history, physical examination, and the results of vital signs, electrocardiogram and clinical laboratory tests performed during the screening visit, as judged by the investigator.

Exclusion Criteria:

• Increased risk of thrombosis, e.g., known history of personal or first-degree relative(s) with unprovoked deep vein thrombosis.
• Any clinical signs or established diagnosis of venous or arterial thromboembolic disease.
• Factor VIII activity greater than or equal to (≥) 150 percent (%) at screening.
• Thrombophilia as identified by any of the below laboratory markers at screening:
• Protein C, protein S or antithrombin less than (<) lower limit of normal (LLN)
• Factor II activity or activated protein C resistance >upper limit of normal (ULN).

According to the Novo Nordisk disclosure commitment on novonordisk-trials.com

The study consists of two parts - an open-label pilot part and a double-blind bioequivalence part.