In vitro and In vivo Drug Metabolism Analysis of BPI-460372 - A Covalent TEAD1/3/4 Inhibitor

Background: BPI-460372 is an orally available, covalent, irreversible small molecule inhibitor of the transcriptional enhanced associate domain (TEAD) 1/3/4, which is currently in clinical development for the treatment of cancers with Hippo pathway alterations. Objective: This study aimed to determine the cytochrome P450 (CYP) phenotyping, metabolic stability, and in vitro and in vivo metabolic profile of BPI-460372. Methods: The CYP phenotyping and metabolic stability were assessed by measuring the depletion of substrate. The metabolic profile in hepatocytes and rat and dog plasma was analyzed using ultra-high-performance liquid chromatography combined with Orbitrap tandem mass spectrometry (UHPLC-Orbitrap-HRMS). Results: BPI-460372 was mainly metabolized by CYP2D6, CYP3A4, and CYP1A2. BPI-460372 exhibited low clearance in human, monkey, and rat hepatocytes, while moderate clearance in dog and mouse hepatocytes. A total of 10 metabolites were identified in five species of hepatocytes, and no human-unique metabolite was detected. In rat plasma and dog plasma, the primary metabolites were M407 (BPI-460430) and M423 (BPI-460456), respectively. The two metabolites were quantitatively determined in rat and dog plasma in pharmacokinetic and toxicological studies. The major metabolic site was 2-fluoro-acrylamide, and major metabolic pathways in hepatocytes, and rat and dog plasma involved oxidative defluorination, hydration, glutathione (GSH) conjugation, hydrolysis, cysteine conjugation, and N-acetyl cysteine conjugation. β-lyase pathway contributed to the metabolism of BPI-460372 in rats to a certain degree. Conclusion: This study elucidated the metabolism of BPI-460372 and provided a basis for pharmacokinetic and toxicological species selection, human pharmacokinetics prediction, and assessment of clinical co-administration limitations and possible metabolic pathways in humans.