Various model systems are utilised during drug development starting from basic research, moving to preclinical research and development for clinical applications in order to identify new drugs to improve human health. However, there are characteristics of humans that are not captured by established models. Such models include homogeneous two-dimensional (2D) cell lines, which lack cellular heterogeneity and physiological relevance, and species differences of animal models. Organoids can mitigate these differences by providing more physiologically relevant three-dimensional (3D) cell models that resemble the molecular state in healthy and pathological tissue. This review presents exemplary approaches using patient-derived organoids (PDOs) that have been developed and the new opportunities that are evolving in drug development with a focus on patient adult stem cell (ASC)-derived organoids. These demonstrate the potential of PDOs used alongside established cell and animal models to improve drug development from basic research to clinical applications such as personalised medicine.