PD168393 is primarily used in research settings as a selective inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase. It is particularly valuable in studies aimed at understanding the role of EGFR signaling in cellular processes, such as proliferation, differentiation, and survival. Researchers utilize PD168393 to investigate the mechanisms of cancer development and progression, as EGFR is often overactive in various types of tumors. Additionally, it helps in exploring potential therapeutic strategies by blocking EGFR activity, which can inhibit tumor growth. This compound is also employed in pharmacological studies to assess the efficacy and specificity of EGFR inhibitors in preclinical models.