An open label, randomized, Three treatment, Three sequence, Three period, Three way crossover, single dose oral bioequivalence study to compare Selexipag 400 microgram film coated tablets versus Uptravi® (selexipag) 400 microgram film coated tablets in fed condition.

Inclusion Criteria:

• Participants aged between 18 to 55 years (both inclusive).
• Participants' weight within normal range according to normal values for Body Mass Index (between 18.50 to 30.00 kg/m2) (both inclusive) with minimum of 45 kg weight.
• Participants with normal health as determined by personal medical history, clinical examination and laboratory examinations within Predefined site Normal range [Annexure III].
• Participants having clinically acceptable 12-lead electrocardiogram (ECG).
• Participants having clinically acceptable chest X-Ray (PA view), if taken.
• Participants having negative urine screen for drugs of abuse (including amphetamines, barbiturates, benzodiazepines, marijuana, cocaine and morphine).
• Participants having negative urine alcohol test / breath alcohol test.
• Non-smoker.
• Participants willing to adhere to the protocol requirements and to provide written informed consent.
• For Male Participants: Participants willing to follow approved birth control methods (a double barrier method) for the duration of the study as judged by the investigator(s), such as (a double barrier method) condom with spermicide, Condom with diaphragm, or abstinence. Participants willing to refrain from donating sperm during the study period
• For Female Participants: Female of child bearing potential practicing an acceptable method of birth control for the duration of the study as judged by the investigator(s), such as intrauterine device (IUD), abstinence, bilateral tubal ligation or double barrier contraception, i.e., condom + diaphragm, condom + spermicidal or foam or Postmenopausal for at least 1 year, or if less than 1 year, then following acceptable contraceptive measures as mentioned above
• Participants having negative urine pregnancy test at screening and negative serum beta-hCG pregnancy test on admission day of period 01 (only for female Participants).

Exclusion Criteria:

• Hypersensitivity to Selexipag or ondansetron, paracetamol, or related class of drugs or any of its excipients.
• History or presence of significant cardiovascular, pulmonary, hepatic, renal, gastrointestinal, endocrine, immunological, dermatological, neurological, urogenital or psychiatric disease or disorder.
• Any treatment which could bring about induction or inhibition of hepatic microsomal enzyme system within 30 days prior to admission in period 01.
• Presence of alcoholism or drug abuse.
• History or presence of asthma, urticaria or other significant allergic reactions.
• History or presence of significant gastric and/or duodenal ulceration.
• History or presence of significant thyroid disease, adrenal dysfunction, organic intracranial lesion such as pituitary tumor.
• History or presence of serotonin syndrome (including altered mental status, autonomic instability and neuromuscular abnormalities) following the concomitant use of ondansetron and other serotonergic drugs (including SSRIs and SNRIs).
• History or presence of cancer or basal or squamous cell carcinoma.
• Difficulty with donating blood.
• Difficulty in swallowing solids dosage form like tablets or capsules.
• Use of any prescribed medication or OTC medication including vaccines, vitamins and herbal remedies during last 30 days prior to admission in period 01.
• Major illness within past 3 months.
• Participant who have donated blood (1 unit) or participation in a drug research study within past 90 days prior to the first dose of the study drug.
• Consumption of xanthine-containing foods or beverages (like chocolate, tea, coffee or cola drinks), tobacco containing products or alcohol or any alcohol containing products within 48.00 hours prior to admission in period 01.
• Consumption of grapefruit or grapefruit juice containing products within 72.00 hours prior to admission of period 01.
• Positive screening test for any one or more: HIV, Hepatitis B and Hepatitis C.
• History or presence of significant easy bruising or bleeding.
• History or presence of significant recent trauma.
• Participants who have been on an abnormal diet (for whatever reason) during the four weeks preceding the study.
• Female Participants who are currently breast feeding.