2.6.3 Metabolism

Hepatic metabolism is assessed through cytochrome P450 (CYP450) substrate and inhibitor profiling across the major isoforms — CYP3A4, CYP2D6, CYP2C9,...

Hepatic metabolism is assessed through cytochrome P450 (CYP450) substrate and inhibitor profiling across the major isoforms — CYP3A4, CYP2D6, CYP2C9, CYP2C19, and CYP1A2 — typically using human liver microsomes (HLM), from which intrinsic metabolic half-life is derived. CYP-mediated drug–drug interaction risk is a major cause of late-stage attrition and post-marketing withdrawal.