A Comparative Pharmacokinetic Study of Fexuprazan 10 mg: Demonstrating Bioequivalence with the Reference Formulation and Evaluating Steady State

Fexuprazan is a potassium-competitive acid blocker approved for treating gastric-acid-related diseases. Although the effectiveness of the recent formulation fexuprazan 10 mg has been demonstrated in Phase 3 clinical trials, data on the pharmacokinetics (PKs) of administering fexuprazan 10 mg twice daily at a 12 h interval are lacking. Moreover, it is imperative to ensure the bioequivalence of the new formulation with the previously approved 40 mg formulation. This study evaluated the pharmacokinetics (PKs) of the single- and multiple-dose oral administration of fexuprazan 10 mg tablets in healthy participants (Part 1) and investigated their bioequivalence with 40 mg tablets (Part 2). Part 1 comprised a single- and multiple-dose, one-sequence, two-period design and eight participants, while Part 2 comprised a single-dose, 2 × 2 crossover design and 24 participants. In Part 1, in Periods 1 and 2, participants received single and multiple doses (twice daily) of fexuprazan 10 mg, respectively. The maximum plasma concentration (C(max)) area under the concentration–time curve from 0 to 12 h (AUC(0–12h)) of the multiple-dose participants was approximately double that of the single-dose participants. In Part 2, the geometric mean ratios (90% confidence intervals) for C(max) and AUC from zero to the time of the last quantifiable concentration (AUC(last)) of the use of four fexuprazan 10 mg tablets to those of one fexuprazan 40 mg tablet were 1.0290 (0.9352–1.1321) and 1.0290 (0.9476–1.1174), respectively, meeting the bioequivalence criteria. Favorable PKs were observed after single and multiple administrations of one fexuprazan 10 mg tablet, and four fexuprazan 10 mg tablets were pharmacokinetically equivalent to one fexuprazan 40 mg tablet.