Combination therapy with insulin-independent sodium-glucose cotransporter 2 inhibitors and thiazolidinedione drugs, such as lobeglitazone, has been reported to elicit potential additive efficacy in glycemic control in type 2 diabetes mellitus. This study was conducted to evaluate the pharmacokinetic (PK) drug–drug interactions between empagliflozin and lobeglitazone in healthy subjects.
A randomized, open-label, multiple-dose study was conducted in 30 healthy subjects using a three-treatment, six-sequence, three-way crossover design. Subjects received one of the following treatments once daily for 5 days in each period: 25 mg empagliflozin, 0.5 mg lobeglitazone sulfate, or a combination. Serial blood sampling before every dose and up to 24 h after the last dose was performed during each treatment period. The PK parameters were estimated using noncompartmental methods with the plasma empagliflozin and lobeglitazone concentrations. The absence of a PK interaction was construed as the 90% confidence interval (90% CI) of maximum concentration at steady state (C max,ss) and area under the concentration-time curve over the dosing interval (AUC tau) for combination therapy-to-monotherapy ratios within the limits of 0.80–1.25.
The steady-state plasma empagliflozin and lobeglitazone concentration-time profiles of combination therapy and monotherapy were comparable in the 25 subjects who completed the study. Coadministration of empagliflozin with lobeglitazone did not affect empagliflozin PK (with 90% CIs of 0.956–1.150 and 0.945–1.133 for C max,ss and AUC tau, respectively). Likewise, empagliflozin did not affect lobeglitazone C max,ss or AUC tau (with 90% CIs of 0.869–0.995 and 0.851–1.018, respectively). All treatment groups tolerated mild adverse events well.
The lack of PK interactions between lobeglitazone and empagliflozin in combination therapy, along with their good tolerability, indicates that the two drugs can be coadministered without dose adjustment.