A Study of Selexipag in Healthy Male Participant

A Single-center, Open-label, Randomized, Formulation Screening, Two-cohort, Four-period, Crossover Study for Selexipag Sustained Release in Healthy Male Subjects

The purpose of this study is to evaluate the pharmacokinetic (PK) of selexipag and ACT-333679 following single oral administration of the matrix tablet and the encapsulated pellets of selexipag, each with 3 different release profiles, as compared to selexipag immediate release (IR) tablets in healthy male participants.

Inclusion Criteria:

• Healthy on the basis of physical examination, medical history, vital signs, and 12-lead electrocardiogram (ECG) performed at screening
• Healthy on the basis of clinical laboratory tests performed at screening. If the results of the serum chemistry panel, hematology, or urinalysis are outside the normal reference ranges, the participants may be included only if the investigator judges the abnormalities or deviations from normal to be not clinically significant. This determination must be recorded in the participant's source documents and initialed by the investigator
• Must sign an informed consent form (ICF) indicating they understand the purpose of, and procedures required for, the study and is willing to participate in the study
• Body mass index (BMI; weight (kilogram [kg]/height^2 [meter {m}]^2) between 18.0 and 28.0 kilogram per square centimeter (kg/m^2) (inclusive), and body weight not less than 50.0 kg at screening
• Blood pressure (after the participant is supine for 5 minutes) between 90 and 145 millimeters of mercury (mmHg) systolic, inclusive, and no higher than 90 mmHg diastolic at screening. If blood pressure is out of range, up to 2 repeated assessments within the screening period are permitted, last assessment being conclusive

Exclusion Criteria:

• Clinically significant abnormal values for hematology, biochemistry, or urinalysis at screening and on Day -1 of Treatment Period 1 as deemed appropriate by the investigator
• Known allergies, hypersensitivity, or intolerance to selexipag or its excipients
• Any contraindication included in the Summary of Product Characteristics (SmPC) of selexipag
• History or clinical evidence of any disease and/or existence of any surgical or medical condition, which might interfere with the absorption, distribution, metabolism or excretion of the study treatments (appendectomy and herniotomy allowed, cholecystectomy not allowed)
• Previous history of stroke, fainting, collapse, syncope, orthostatic hypotension, vasovagal reactions, head injury