Evaluation of a New Formulation That Improves the Bioavailability and Food Effect of Abiraterone: An Open-Label, Crossover, Randomized, Controlled, Phase I Clinical Trial.

This first-in-human phase I trial evaluated RL001, a self-emulsifying soft-capsule abiraterone developed to overcome the low bioavailability and food sensitivity associated with the 1000-mg Zytiga tablet that is used with prednisone according to NCCN guidelines. Plasma concentrations were quantified by LC-MS/MS and modeled in Phoenix WinNonlin 8.1 and SAS; GeoMean confidence intervals compared pharmacokinetics. Against 1000-mg abiraterone acetate tablet, the 200 mg RL001 achieved abiraterone Cmax GMR >125% and AUC0-t, AUC0-∞ 80-125%, indicating higher bioavailability and enabling a lower therapeutic dose. The GMR of prednisone and its metabolite remained within 80%-125%, confirming no interaction. Fed/fasted exposure ratios stayed around 80% for AUC and <80% for Cmax, eliminating food spikes. Hyperbilirubinemia and hypertriglyceridemia were significantly less frequent. The abiraterone self-emulsifying soft capsule represents a safer and more convenient therapeutic option in the management of prostate cancer.