GDC-0326 is primarily used in research settings for its potent and selective inhibition of BTK (Bruton's tyrosine kinase). It is designed to target both wild-type and C481S-mutant forms of BTK, making it valuable in studying resistance mechanisms in B-cell malignancies. Its application is especially relevant in the development of therapies for cancers such as chronic lymphocytic leukemia and non-Hodgkin’s lymphoma. Due to its irreversible binding mechanism, GDC-0326 enables sustained suppression of BTK signaling, which helps in evaluating long-term pathway inhibition in preclinical models. It is not intended for clinical use but serves as a critical tool compound in oncology and immunology research.