Protocol Receptor Occupancy Assay
BACKGROUND: Vedolizumab is a monoclonal antibody approved for use in ulcerative colitis and Crohn's disease. By specifically binding to α4 β7 integrin, vedolizumab prevents trafficking of lymphocytes to the gut, thereby interfering with disease pathology. During the clinical development program, the pharmacodynamic effect of vedolizumab was evaluated by 2 flow cytometry receptor occupancy assays: act-1 (ACT-1) and mucosal addressin cell adhesion molecule-1 (MAdCAM-1). Here we describe the development and validation of these assays.METHODS: The ACT-1 assay is a receptor occupancy free-site assay that uses a monoclonal antibody with the same binding epitope as vedolizumab to detect free (unbound) sites on α4 β7 integrin. Knights of the old republic 3. The MAdCAM-1 assay used a soluble version of the natural ligand for α4 β7 integrin to detect free sites.
The assays were validated using a fit-for-purpose approach throughout the clinical development of vedolizumab.RESULTS: Both the ACT-1 assay and the MAdCAM-1 assay demonstrated acceptable reproducibility and repeatability. The assays were sufficiently stable to allow for clinical use. During clinical testing the assays demonstrated that vedolizumab was able to saturate peripheral cells at all doses tested.CONCLUSIONS: Two pharmacodynamic receptor occupancy assays were developed and validated to assess the effect of vedolizumab on peripheral blood cells. The results of these assays demonstrated the practical use of flow cytometry to examine pharmacodynamic response in clinical trials.
Flow cytometry can be a powerful tool for the evaluation of Receptor Occupancy (RO) to provide an assessment of the therapeutic binding to the target receptor. This can be evaluated using direct or indirect methods. Please inquire to start the scientific discussion.Receptor occupancy assays are a method for identifying, and monitoring the binding of a therapeutic to its cellular target. These assays can be as simple as measuring the number of cell surface receptors bound by a therapeutic agent or highly complex such as measuring receptor dynamics, depending on the scientific questions being studied.
Receptor Occupancy Assay Protocol
The nature of Receptor Occupancy assay research necessitates development and validation of a new assay for each study drug and each assay presents new challenges to overcome. As development of personalized cancer treatments continue to progress, the need for Receptor. Receptor Occupancy Protocol 2 EX VIVO RECEPTOR OCCUPANCY ASSAY Animal dosing and tissue collection Animals are administered the test article (oral, i.p., s.c or i.v) or vehicle alone. After allowing for tissue uptake and distribution, the animals are sacrificed and the brain or other organs removed. Dec 24, 2015 When running a receptor occupancy assay in the context of a clinical trial, data must be able to be compared in a longitudinal manner. In this case, day to day variability must be taken into account. Since not just frequency of target cell populations is assessed, but also fluorescence output of labelled reagents, steps should be taken to.