Patrys Limited announced that it has selected an optimised stable cell line for its lead asset PAT-DX1. This important step allows the company to establish large- scale production of PAT-DX1 deoxymab for final preclinical studies, first-in-man studies, and partnering activities. The establishment of a stable, PAT-DX1-producing cell line by Patrys is the culmination of a manufacturing development and optimisation program that was initiated in mid-2019. The development program included modification of PAT-DX1's protein back-bone to improve its properties for use in human therapeutic applications. Cell lines expressing the modified PAT-DX1 were developed and an extensive selection processes was conducted to identify single, clonal cell lines that produced high yields of high quality PAT-DX1. The final step was to ensure that the cell line was stable and able to deliver reproducible and consistent production of PAT-DX1 protein over time. Over the past months Patrys evaluated six different optimised cell lines and has selected a best performer from these studies. The cell line that has been selected will be stored as a Master Cell Bank (MCB) which will form the basis for all future production of PAT-DX1. The selection of a stable cell line for producing PAT-DX1 means that all future studies undertaken by either Patrys or its partners and collaborators can be based on suitably qualified product, including supporting ongoing research effort being conducted around the globe on this technology. Having a consistent and qualified product means that data can potentially be leveraged from a broad range of studies covering applications such as therapeutics, nanoparticle drug delivery, antibody-drug conjugation and diagnostic imaging agents.