Used in research settings as a selective inhibitor of protein arginine deiminase 4 (PAD4), NG-52 helps study the role of PAD4 in diseases involving citrullination, such as rheumatoid arthritis, lupus, and certain cancers. It is valued for its ability to cross cell membranes and inhibit PAD4 activity in cellular models, making it a useful tool compound for probing inflammatory and autoimmune pathways. NG-52 is not used clinically but supports drug discovery efforts aimed at developing therapies targeting aberrant citrullination.