A Study to Evaluate How Aprocitentan is Safe and How it is Absorbed and Broken Down in the Body of Japanese and Caucasian Subjects

Inclusion Criteria: * Subjects must be of Caucasian or Japanese ethnicity * Signed informed consent in a language understandable to the subject prior to any study-mandated procedure * Body mass index (BMI) of 18.0 to 28.0 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 * A woman of childbearing potential is eligible only if the following applies: Negative serum pregnancy test at Screening, Negative urine pregnancy test on Day -1, Agreement to consistently and correctly use a reliable method of contraception from Screening up to at least 30 days after last study treatment administration Japanese subjects only * Subjects must be of native Japanese descent (all parents/grandparents of Japanese descent). * Subjects must not have been away from Japan for more than 10 years (at Screening visit). * Subject's lifestyle should not have changed significantly since relocation from Japan Exclusion Criteria: * Previous exposure to aprocitentan and/or macitentan. * Known hypersensitivity to aprocitentan or treatments of the same class, or any of the excipients * Pregnant or lactating women * Any circumstances or conditions, which, in the opinion of the investigator, may affect full participation in the study or compliance with the protocol