Keywords: Companion Diagnostics, IHC, Precision Medicine, Analytical Validation
In recent drug development, novel biomarkers have been employed in diagnostic procedures, known as companion diagnostics (CDx), for the safe and effective use of its corresponding drug. In developing CDx devices, different technologies, such as immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), polymerase chain reaction (PCR), next-generation sequencing (NGS), etc. have been implemented. Among these CDx devices, IHC assays, which are based on the localization of antigens in tissue sections using specific primary antibodies, have been widely used to detect many well-known genetic markers such as HER2, PD-L1, ALK, etc. in the development of CDx devices for different therapeutic products. Normally, the assay is visualized with light or fluorescence microscopy by a trained pathologist once the antibody-antigen binding occurs. In this talk, we will discuss statistical issues and consideration in validating CDx devices especially for IHC assays from a regulatory perspective. We will mainly focus on the analytical validation.