Navigate BioPharma Services, Inc. has introduced a new assay for quantifying pharmacodynamic markers of radioligand therapies in tumors.

The development of this assay was presented in a poster entitled ‘Quantifying pharmacodynamic markers of radioligand therapies (RLTs) in tumor by multiplex immunofluorescence and automated quantitative analysis (AQUA) algorithms’ at the American Association for Cancer Research (AACR) 2024 Annual Meeting held in San Diego, CA.

Navigate BioPharma Services' new image-based test measures the changes in the cancer cells and the tissue after RLT. This innovative assay utilizes multiplex immunofluorescence (mIF) combined with automated quantitative analysis (AQUA) algorithms to precisely measure changes in key protein markers within tumor tissues following radioligand therapy. For example, ionizing radiation produced by radioisotopes linked to antibodies causes double-stranded breaks either directly or via generation of reactive oxygen species.

This type of DNA damage is associated with an increase in markers for cell cycle arrest (e.g., p21/CIP1) and DNA repairing proteins (e.g., CHK2 and gH2Ax). Additionally, proliferating cells (identifiable by Ki67) are most susceptible to ionizing radiation as DNA is exposed during mitotic phase of cell cycle. These biologically verified markers are incorporated into a single multiplexed fluorescence immunohistochemistry (mFIHC) assay for robust quantitation of the pharmacodynamic activity of RLTs and to gain insights into DNA damage response and mechanism of efficacy from minimal tumor biopsy. This approach offers a comprehensive exploration of a therapy's impact on cell cycle and DNA damage within a tumor and tumor microenvironment.

"Radioligand therapies hold immense promise for targeted cancer treatment," said Jennifer Bordeaux, PhD, Associate Director of Digital Pathology at Navigate BioPharma Services.

"Our new assay provides drug developers with a powerful tool to assess the therapeutic effects of these agents, ultimately accelerating drug development and improving patient outcomes," Bordeaux added.