Bioequivalence Study to Compare Selexipag 400mcg Film Coated Tablets (400 mcg Selexipag) Versus Uptravi® 400mcg Film Coated Tablets (400 mcg Selexipag)

Inclusion Criteria: * The subject is Caucasian \& aged between eighteen to fifty (18-50), both inclusive. * The subject is within the limits for his/her height \& weight as defined by the body mass index range (18.5 - 30.0 Kg/m2). * The subject is willing to undergo the necessary pre- \& post- medical examinations set by this study. * The results of medical history, physical examination, vital signs \& conducted medical laboratory tests are normal as determined by the clinical investigator. * The subject tested negative for Hepatitis B (HBsAg), Hepatitis C (HCVAb) and human immunodeficiency virus (HIVAb). * There is no evidence of psychiatric disorder, antagonistic personality, and poor motivation, emotional or intellectual problems likely to limit the validity of consent to participate in the study or limit the ability to comply with protocol requirements. * The subject is able to understand and willing to sign the informed consent form. * For female subjects: negative serum pregnancy test and the married woman is using two reliable contraception methods and should be non-lactating. * The subject has normal cardiovascular system \& normal ECG with normal QT interval corrected for heart rate according to Bazett's formula. * The subject kidney and liver (AST \& ALT enzymes) functions tests are within normal range. (Creatinine is accepted if below the reference range after being evaluated by the clinical investigator as clinically not significant). * The subject Haematology test results are within normal range \& RBC indices are within 5% of the normal range. * The subject blood pressure is ≥ 110/70 mmHg before dosing. * The subject has normal thyroid gland function. Exclusion Criteria: * The subject is a heavy smoker (more than 10 cigarettes per day). * The subject has a history of or concurrent abuse of alcohol. * The subject has a history of or concurrent abuse of illicit drugs. * The subject has a history of hypersensitivity and/or contraindications to the study drug and any related compounds. * The subject has suffered an acute illness one week before dosing. * The subject has been hospitalized within three months before the study or during the study. * The subject is on special diet (for example subject is vegetarian.) * The subject has consumed caffeine or xanthine containing beverages or foodstuffs within two days before dosing and until 72 hours after dosing in both study periods. * The subject has taken a prescription medication within two weeks or even an over the counter product (OTC) within one week before dosing in each study period and any time during the study, unless otherwise judged acceptable by the clinical investigator. * The subject has taken grapefruit/orange containing beverages or foodstuffs within seven (7) days before first dosing and any time during the study. * The subject has been participating in any clinical study (e.g. pharmacokinetics, bioavailability and bioequivalence studies) within the last 80 days prior to the present study. * The subject has donated blood within 80 days before first dosing. * The subject has a history or presence of cardiovascular, pulmonary, renal, hepatic, gastrointestinal, hematological, endocrinal, immunological, dermatological, neurological, musculoskeletal, ocular or psychiatric diseases. * The subject has consumed drugs that may affect pharmacological or pharmacokinetic properties of Selexipag (for example: gemfibrozil, clopidogrel, deferasirox, teriflunomide, rifampicin, carbamazepine, phenytoin, valproic acid, probenecid, fluconazole, lopinavir/ritonavir). two weeks before dosing, during the study and two weeks after dosing. * The subject has recently experienced significant blood loss or fluid loss such as severe diarrhoea or vomiting. Note: Subjects, who were screened for another study and were not enrolled, might be recruited for this study provided they meet the acceptance criteria of the study.