Precision Medicine: The Function Of Receptor Occupancy In Drug Development

Over the last two decades, flow cytometry has increasingly been utilized during both early and late phases of drug development. Instruments are now able to simultaneously measure over 50 parameters at the single-cell level and within complex mixtures of cells with significant precision. Along with immunophenotyping and functional testing used for clinical immune monitoring, receptor occupancy (RO) assays have become a standard application in flow cytometry in the context of drug development, particularly in indications where biologics are the therapeutic modality. In this chapter, we aim to discuss the various assay formats of receptor occupancy and outline some of the advantages and disadvantages related to specific assay designs with potential technical and analytical pitfalls.