Continued clinical efficacy demonstrations of cell-based immunotherapies (iTx) such as chimeric antigen receptor T cell (CAR-T) therapies has made the prospect increasingly likely of an immunotherapy product achieving conditional market authorization in the short term. For example, Novartis and the University of Pennsylvania’s lead candidate (CTL019) for treating a range of hematological malignancies received breakthrough status from the US Food and Drug Administration (FDA) in 2014, permitting access to an expedited drug development pathway for high unmet medical needs (1).…