Lumiracoxib: Pharmacokinetic and Pharmacodynamic Profile When Coadministered with Fluconazole in Healthy Subjects

This two-way crossover study evaluated the effect of fluconazole on the pharmacokinetics and selective COX-2 inhibition of lumiracoxib. Thirteen healthy subjects were randomized to fluconazole (day 1: 400 mg; days 2-4: 200 mg) or no drug. On day 4, all subjects received a single dose of lumiracoxib (400 mg). Lumiracoxib pharmacokinetics were assessed during the following 48 hours. Thromboxane B 2 (TxB 2 ) inhibition was measured prior to lumiracoxib dosing and 2 hours afterwards. Fluconazole caused a small (18%) but not clinically relevant increase in lumiracoxib mean AUC 0 - ∞ but had no effect on lumiracoxib mean C m a x . The geometric mean ratio (lumiracoxib plus fluconazole/ lumiracoxib alone) for A AUC 0 - ∞ was 1.19 (90% confidence interval [CI] = 1.12, 1.27) and for C m a x was 1.11 (90% CI = 0.98, 1.27). The decrease in TxB 2 from predose was not significantly different for lumiracoxib (11.8%) or lumiracoxib plus fluconazole (7.1 %); no correlation between lumiracoxib concentration and TxB 2 decrease was seen. As fluconazole is a strong inhibitor of cytochrome P450 (CYP) 2C9, other CYP2C9 inhibitors are unlikely to affect lumiracoxib pharmacokinetics with clinical relevance, making dosage adjustment unnecessary.