Clinical study in healthy adult subjects to compare the adult tablet of selexipag with the tablet developed for children.

Healthy male adults receive a single dose of selexipag (200 µg) but using a different tablet strength (4 film-coated pediatric tablets of 50 µg versus one film-coated tablet of 200 µg selexipag) during each of the two study periods. There is a washout of 7-9 days between the two study treatment administrations.

Key inclusion Criteria:

• Male subjects aged from 18 to 45 years (inclusive) at screening
• Signed informed consent form
• Body mass index (BMI) between 18.0 and 28.0 kg/m2 (inclusive) at screening
• Healthy on the basis of physical examination,cardiovascular assessments and laboratory tests

Key exclusion Criteria:

• Any contraindication to the study treatments
• History or clinical evidence of any disease or medical / surgical condition or treatment, which may put the subject at risk of participation in the study or may interfere with the absorption, distribution, metabolism or excretion of the study treatments
• Any circumstances or conditions, which, in the opinion of the investigator, may affect the subject's full participation in the study or compliance with the protocol