The study will investigate the effect of rifampicin on the uptake and breakdown of ACT-246475 in healthy subjects

Inclusion Criteria:

• Signed informed consent in a language understandable to the subject prior to any study-mandated procedure
• Healthy male and female subjects aged between 18 and 65 years (inclusive) at Screening
• Body mass index of 18.0 to 30.0 kg/m2 (inclusive) at Screening
• Systolic blood pressure 100-145 mmHg, diastolic blood pressure 50-90 mmHg, and pulse rate 45-90 bpm (inclusive), measured on the same arm, after 5 min in the supine position at screening and on Day -1 of the first period
• Hematology and coagulation test results not deviating from the normal range to a clinically relevant extent at Screening and on Day -1 of the first period
• Women of childbearing potential must have a negative serum pregnancy test at Screening and a negative urine pregnancy test on Day- 1 of the first treatment period and must agree to consistently and correctly use a highly effective method of contraception

Exclusion Criteria:

• Previous exposure to ACT-246475.
• Previous exposure to rifampicin within 3 months prior to Screening.
• Known hypersensitivity to P2Y12 receptor antagonists or rifampicin, or to any of the rifamycins, or any of their excipients
• Loss of 250 mL or more of blood within 3 months prior to Screening
• Any circumstances or conditions, which, in the opinion of the investigator, may affect full participation in the study or compliance with the protocol
• Family or personal history of prolonged bleeding (e.g., after surgical intervention) or bleeding disorders (e.g., thrombocytopenia, clotting disturbances), intracranial vascular diseases, stroke, reasonable suspicion of vascular malformations, or peptic ulcers
• Known platelet disorders (e.g., Glanzmann thromboasthenia, von Willebrand disease, platelet release defect)