PHARMACOGENOMICS IN PRECISION MEDICINE: MOLECULAR DETERMINANTS OF DRUG RESPONSE, TOXICITY, AND PERSONALIZED THERAPEUTIC STRATEGIES

Abstract

Pharmacogenomics has emerged as a key component of precision medicine by explaining how genetic variation contributes to differences in drug response, therapeutic efficacy, and susceptibility to adverse effects. Variability in drug-metabolizing enzymes, transporters, molecular targets, and signaling pathways can influence both pharmacokinetic and pharmacodynamic outcomes. This comprehensive review aimed to synthesize current evidence on the molecular and genetic determinants of drug response and toxicity and to examine their application in pharmacogenomics-guided precision medicine and personalized therapeutic strategies. Relevant peer-reviewed literature was identified through major scientific databases using terms related to pharmacogenomics, precision medicine, genetic variation, drug metabolism, drug transport, adverse drug reactions, and personalized therapy. The selected studies were organized into major thematic areas covering molecular mechanisms, toxicity, clinical applications, genomic technologies, implementation, and future directions. The reviewed evidence showed that genetic variation can alter drug metabolism, transport, target sensitivity, and toxicity risk. Pharmacogenomics-guided strategies have potential applications in oncology, cardiovascular medicine, psychiatry, infectious diseases, and other therapeutic areas. Genomic technologies and biomarker-based approaches are increasingly supporting individualized drug and dose selection, although challenges remain in population diversity, variant interpretation, clinical validation, accessibility, and routine implementation. Pharmacogenomics provides a strong molecular foundation for improving treatment efficacy and safety. Continued clinical validation and integration with broader biological and clinical information are essential for advancing personalized pharmacotherapy.