Study to Evaluate Safety and Tolerability of ACT-709478 in Healthy Subjects

Inclusion criteria

• Signed informed consent form
• Healthy male and female subjects aged between 18 and 55 years (inclusive) at screening
• Negative serum pregnancy tests at screening and negative urine pregnancy test at Day -1 for women and agreement to use 2 reliable methods of contraception for at least 3 months after last study drug administration
• Body mass index of 18.0 to 29.9 kg/m2 (inclusive) at screening
• Systolic blood pressure 100-140 mmHg, diastolic blood pressure 50-90 mmHg, and pulse rate 50-90 bpm (inclusive), measured after 5 minutes in the supine position at screening and on Day -1
• Healthy on the basis of physical examination, cardiovascular, ophthalmological, neurological assessments and laboratory tests

Exclusion criteria

• Known hypersensitivity to ACT-709478 or drugs of the same class, or any of their excipients
• 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
• QT interval corrected with Fridericia's formula (QTcF) > 450 ms (using the ECG machine HR correction method) at screening and on Day -1
• Treatment with another investigational treatment within 2 months or 5 t1/2 (whichever is the longest) prior to screening or participation in more than four investigational treatment studies within 1 year 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