Bioequivalence Study Between GSK3542503 Hydrochlorothiazide + Amiloride Hydrochloride 50 mg: 5 mg Tablets and Reference Product in Healthy Adult Participants Under Fasting Conditions

The combination of the diuretics amiloride hydrochloride (HCl) and hydrochlorothiazide (HCTZ) (GSK3542503) is indicated for the treatment of hypertension, congestive heart failure and hepatic cirrhosis with ascites and edema. This first time in human (FTIH) study is aimed to determine whether the test product GSK3542503 is bioequivalent to the reference (ref) hydrochlorothiazide 50 milligram (mg)/amiloride hydrochlorothiazide 5 mg in healthy adult participants under fasting conditions based on pharmacokinetic (PK) endpoints. This is a phase I, open label, balanced, randomized, single dose, two-way crossover study, enroling approximately 42 healthy participants at a single center. Study participants will be randomized to one of two treatment sequences (A-B or B-A) in accordance with the randomization schedule. A single dose of one of the two treatments A (Test: GSK3542503, a hydrochlorothiazide 50 mg and amiloride hydrochloride 5 mg fixed dose combination) or B (Reference: Moduretic, a hydrochlorothiazide 50 mg and amiloride hydrochloride 5 mg fixed dose combination), will be administered on Day 1, in each treatment period. Each participant will participate in both treatment periods and receive a single dose of each treatment. The treatment periods will be separated by a washout period of at least 7 days and no more than 14 days. The total duration in the study for each participant is expected to be 5 to 7 weeks, from screening to his or her last visit. A maximum of 42 participants will be randomized such that at least 32 evaluable participants complete the study.