In a rapidly shifting landscape of personalized medicine, biomarkers have become central to shaping the way drug development and clinical trials unfold. From predicting therapeutic response to identifying optimal patient populations, the complexity and scope of biomarker use has increased alongside technological advances. A key success story like the BCR-ABL biomarker in chronic myeloid leukemia demonstrates the power of targeted medicine, which has raised five-year survival rates from around 30–50% to over 90%. With the rise of multi-omics and AI-driven analytics, the industry is entering a new era of integration, data complexity—and unprecedented possibility.