Posaconazole Tablet Pharmacokinetics: Lack of Effect of Concomitant Medications Altering Gastric pH and Gastric Motility in Healthy Subjects

Posaconazole oral suspension is an extended-spectrum triazole that should be taken with food to maximize absorption. A new posaconazole tablet formulation has demonstrated improved bioavailability over the oral suspension in healthy adults in a fasting state. This study evaluated the effects of concomitant medications altering gastric pH (antacid, ranitidine, and esomeprazole) and gastric motility (metoclopramide) on the pharmacokinetics of posaconazole tablets. This was a prospective open-label 5-way crossover study in 20 healthy volunteers. In each treatment period, a single 400-mg dose (4 100-mg tablets) of posaconazole was administered alone or with 20 ml antacid (2 g of aluminum hydroxide and 2 g of magnesium hydroxide), ranitidine (150 mg), esomeprazole (40 mg), or metoclopramide (15 mg). There was a ≥10-day washout between treatment periods. Posaconazole exposure, time to maximum concentration of drug in serum (T_max), and apparent terminal half-life (t_1/2) were similar when posaconazole was administered alone or with medications affecting gastric pH and gastric motility. Geometric mean ratios (90% confidence intervals [CIs]) of the area under the concentration-time curve from time zero to infinity (AUC_0–inf) (posaconazole with medications affecting gastric pH and gastric motility versus posaconazole alone) were 1.03 (0.88–1.20) with antacid, 0.97 (0.84–1.12) with ranitidine, 1.01 (0.87–1.17) with esomeprazole, and 0.93 (0.79–1.09) with metoclopramide. Geometric mean ratios (90% CIs) of the maximum concentration of drug in serum (C_max) were 1.06 (0.90–1.26) with antacid, 1.04 (0.88–1.23) with ranitidine, 1.05 (0.89–1.24) with esomeprazole, and 0.86 (0.73–1.02) with metoclopramide. In summary, in healthy volunteers, the pharmacokinetics of a single 400-mg dose of posaconazole tablets was not altered to a clinically meaningful extent when posaconazole was administered alone or with medications affecting gastric pH or gastric motility.