[18F]Fluorodeoxyglucose (FDG)-PET combined with CT is increasingly being used as an imaging tool in oncology clinical trials. Progress in the standardization and harmonization of acquisition and analysis protocols for FDG-PET/CT has been made, although there are still areas for which further guidance is needed. Standardizing FDG-PET/CT clinical trial design and interpretation will contribute to increased efficiency and precision in decision-making for drug development. This feature review highlights areas in FDG-PET/CT imaging, particularly image analysis and response classification, that currently require expert guidance or further research to optimize the application of this tool in oncological drug development.