Use of Tissue Biopsies to Improve Clinical Trials

Clinical trials, primarily those used for registration of drugs or medical devices, typically measure the effect of the intervention on how the patient feels, functions, or survives, which are typically designated as primary or secondary trial endpoints. With the exception of well-validated surrogate biomarkers such as blood pressure or hemoglobin A1c, many analytical biomarker measurements originate from fluid samples or imaging tests and are designated as exploratory trial endpoints. Many diseases including cancer and autoimmune diseases manifest as a tissue lesion, diagnosis of which is ascertained by examining a fixed tissue sample stained with hematoxylin and eosin (H&E) by microscopy, but due to cost and perceived burdens on the patient the use of biopsies in clinical trials has historically been limited. However, with recognition that the tissue lesion is frequently where drug action can be observed, the use of tissue biopsies in clinical trials has increased over the past decade, particularly in oncology. With the advent of multi-omic testing, there is increased desire to extract as much information as possible from precious yet limiting tissue samples from each patient while improving the overall efficiency of drug development. The objectives of this talk are to: 1) review the critical importance of tissue biopsies in some types of clinical trials, 2) discuss some of the technical and operational factors to be considered when implementing analysis of tissue biopsies in a trial setting, and 3) highlight examples of data and insights that can be obtained from tissue biopsies.