Advancing Predictions of Oral Drug Absorption, CYP3A4 Induction, and Transporter-Mediated Interactions Using a Human Primary Intestinal 3D Model (EpiIntestinal™)

Accurate prediction of oral drug absorption in humans is essential for early drug development; however, physiologically relevant human models are lacking. This study aims to comprehensively assess the EpiIntestinal™, a human primary intestinal 3D model, for its ability to predict oral absorption (F_a), intestinal availability (F_g), CYP3A4 induction, and drug-drug interactions (DDIs). The model showed clinically relevant expression of a key drug-metabolizing Enzymes, transporters, and a nuclear receptor, pregnane X receptor (PXR). The model demonstrated a moderate improvement over Caco-2 in correlating permeability coefficients with human absorption data for a set of 18 drugs. However, PBPK modeling, using EpiIntestinal™ permeability data, accurately predicted the clinical maximum plasma concentration (C_max) of the P-gp substrates digoxin and dabigatran etexilate, unlike the significant underpredictions from Caco-2 data. PBPK modeling using intrinsic clearance and permeability data from EpiIntestinal™ accurately predicted human F_g for CYP3A4/5 substrate drugs (except buspirone). Furthermore, the model demonstrated the induction of CYP3A4 and P-gp (threefold) by a strong PXR inducer, rifampicin. Combining induction parameters of rifampicin from EpiIntestinal™ with those from the TruVivo (human hepatic model) into PBPK modeling accurately captured DDI effects on midazolam, a sensitive CYP3A4/5 substrate. Additionally, the model accurately predicted clinical outcomes of P-glycoprotein (P-gp) and breast Cancer resistance protein (BCRP) mediated DDIs for ARV-471. These data underscore the potential of EpiIntestinal™ in predicting human F_a and F_g, and in quantitatively assessing CYP3A4 induction and transporter-based DDIs.