Simulating Healthy Participant Pharmacokinetics for Renal and Hepatic Impairment Studies: Retrospective Assessment of the Approach.

The recruitment of a parallel, healthy participants (HPs) arm in renal and hepatic impairment (RI and HI) studies is a common strategy to assess differences in pharmacokinetics. Limitations in this approach include the underpowered estimate of exposure differences and the use of the drug in a population for which there is no benefit. Recently, a method was published by Purohit et. al. (2023) that leveraged prior population pharmacokinetic (PopPK) modeling-based simulation to infer the distribution of exposure ratios between the RI/HI arms and HPs. The approach was successful, but it was a single example with a robust model having several iterations of development and fitting to extensive HP data. To test in more studies and models at different stages of development, our catalogue of RI/HI studies was searched, and those with suitable properties and from programs with available models were analyzed with the simulation approach. There were 9 studies included in the analysis. Most studies were associated with models that would have been available at the time (ATT) of the study, and all had a current, final model. For 3 studies, the HP PK was not predicted well by the ATT (2) or final (1) models. In comparison to conventional analysis of variance (ANOVA), the simulation approach provided similar point estimates and confidence intervals of exposure ratios. This PopPK based approach can be considered as a method of choice in situations where the simulation of HP data would not be an extrapolation, and when no other complicating factors are present.

Assessment of the Drug Interaction Potential of Ertugliflozin With Sitagliptin, Metformin, Glimepiride, or Simvastatin in Healthy Subjects.

Ertugliflozin, a sodium-glucose cotransporter 2 inhibitor for the treatment of adults with type 2 diabetes mellitus, is expected to be coadministered with sitagliptin, metformin, glimepiride, and/or simvastatin. Four separate open-label, randomized, single-dose, crossover studies were conducted in healthy adults to assess the potential pharmacokinetic interactions between ertugliflozin 15 mg and sitagliptin 100 mg (n = 12), metformin 1000 mg (n = 18), glimepiride 1 mg (n = 18), or simvastatin 40 mg (n = 18). Noncompartmental pharmacokinetic parameters derived from plasma concentration-time data were analyzed using mixed-effects models to assess interactions. Coadministration of sitagliptin, metformin, glimepiride, or simvastatin with ertugliflozin had no effect on area under the plasma concentration-time profile from time 0 to infinity (AUCinf ) or maximum observed plasma concentration (Cmax ) of ertugliflozin (per standard bioequivalence boundaries, 80% to 125%). Similarly, ertugliflozin did not have any impact on AUCinf or Cmax of sitagliptin, metformin, or glimepiride. AUCinf for simvastatin (24%) and simvastatin acid (30%) increased slightly after coadministration with ertugliflozin and was not considered clinically relevant. All treatments were well tolerated. The lack of clinically meaningful pharmacokinetic interactions demonstrates that ertugliflozin can be coadministered safely with sitagliptin, metformin, glimepiride, or simvastatin without any need for dose adjustment.