A Study to Compare the Macitentan-tadalafil Fixed Dose Combination Tablet Relative to the Concomitant Administration of the Reference Tablets of Macitentan and Tadalafil in Healthy Subjects

Key Inclusion Criteria: * Signed informed consent * Male and female subjects aged between 18 and 55 years (inclusive) at screening * Healthy on the basis of the physical examination, vital signs, 12-lead ECG, and laboratory tests performed at screening * Women must have a negative serum pregnancy test at screening and a negative urine pregnancy test on Day-1 or must be of non-childbearing potential. * Body mass index (BMI) 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) Key Exclusion Criteria: * Known hypersensitivity to any active substance or drugs of the same class, or any excipients of the drug formulation(s) * 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 treatment(s) * Values of hepatic aminotransferase (alanine aminotransferase \[ALT\] and/or aspartate aminotransferase \[AST\]) \> 3 X upper limit of normal at screening * Loss of vision in one eye because of non-arteritic anterior ischemic optic neuropathy * Known hereditary degenerative retinal disorders, including retinitis pigmentosa * Priapism and anatomical deformation of the penis * Previous history of fainting, collapse, syncope, orthostatic hypotension, or vasovagal reactions * Treatment with another investigational drug within 3 months prior to screening or participation in more than 4 investigational drug studies within 1 year prior to screening * Excessive caffeine consumption, defined as \> or = 800 mg per day at screening. * Nicotine intake (e.g., smoking, nicotine patch, nicotine chewing gum, or electronic cigarettes) within 3 months prior to screening and inability to refrain from nicotine intake from screening until end-of-study (EOS; washout period included) * Previous treatment with any prescribed medications (including vaccines) or over the counter (OTC) medications within 3 weeks prior to first study treatment administration. * Any circumstances or conditions, which, in the opinion of the investigator, may affect full participation in the study or compliance with the protocol.