Vortioxetine is approved for the treatment of major depressive disorder (MDD). This analysis aimed to develop pharmacokinetic (PK) and PK/Efficacy models to evaluate the exposure-response relationship for vortioxetine in patients with MDD. PK data from 10 MDD and two generalized anxiety disorder studies of vortioxetine (3160 patients), and efficacy data [Montgomery-Åsberg Depression Rating Scale (MADRS)] from seven MDD studies (2537 patients), were used for the development of PK and PK/Efficacy models. One- and two-compartment models were evaluated as structural PK models, and linear and nonlinear (Emax) models were used to describe the relationship between average vortioxetine concentration at steady-state (Cav) and change in MADRS score from baseline (ΔMADRS). The impact of selected covariates on the PK and efficacy parameters of vortioxetine was also investigated. PK of vortioxetine was best characterized by a two-compartment model with first-order absorption and elimination. Mean estimates for oral clearance (CL/F) and volume of distribution for the central compartment of vortioxetine were 42 L/hr and 2920 L. Creatinine clearance, height and geographic region had statistically significant effects on vortioxetine CL/F, but the effect of each of these covariates was not considered clinically relevant, as they lead to ±26% change in area under the curve or Cmax of vortioxetine. An Emax model best described the relationship between ΔMADRS and Cav. Half-maximal effective concentration (EC50) and Emax estimates were 24.9 ng/mL and 7.0. No identified covariates, except region, had clinically meaningful effects on vortioxetine efficacy. These PK/Efficacy models adequately characterized the vortioxetine exposure-response relationship.
© 2015 The Authors/Takeda Pharmaceuticals USA. Basic & Clinical Pharmacology & Toxicology published by John Wiley & Sons Ltd on behalf of Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).