Pharmacokinetic interactions between fexuprazan, a potassium‐competitive acid blocker, and nonsteroidal anti‐inflammatory drugs in healthy males

Abstract Fexuprazan, a novel potassium‐competitive acid blocker, is expected to be used for the prevention of nonsteroidal anti‐inflammatory drugs (NSAIDs) induced ulcer. This study aimed to evaluate pharmacokinetic (PK) interactions between fexuprazan and NSAIDs in healthy subjects. A randomized, open‐label, multicenter, six‐sequence, one‐way crossover study was conducted in healthy male subjects. Subjects randomly received one of the study drugs (fexuprazan 40 mg BID, celecoxib 200 mg BID, naproxen 500 mg BID, or meloxicam 15 mg QD) for 5 or 7 days in the first period followed by the combination of fexuprazan and one of NSAIDs for the same days and the perpetrator additionally administered for 1–2 days in the second period. Serial blood samples for PK analysis were collected until 48‐ or 72‐h post‐dose at steady state. PK parameters including maximum plasma concentration at steady state ( C max,ss ) and area under plasma concentration–time curve over dosing interval at steady state (AUC τ,ss ) were compared between monotherapy and combination therapy. The PKs of NSAIDs were not significantly altered by fexuprazan. For fexuprazan, differences in PK parameters (22% in C max , 19% in AUC τ,ss ) were observed when co‐administered with naproxen, but not clinically significant. The geometric mean ratio (90% confidence interval) of combination therapy to monotherapy for C max,ss and AUC τ,ss was 1.22 (1.02–1.46) and 1.19 (1.00–1.43), respectively. There were no significant changes in the systemic exposure of fexuprazan by celecoxib and meloxicam. Fexuprazan and NSAIDs did not show clinically meaningful PK interactions.