Jia Ruan, MD, PhD, Weill Cornell Medicine, New York, NY, discusses the importance of understanding the biology of peripheral T-cell lymphoma as well as the mechanism of action of novel agents. An improved understanding would allow the identification of mutations of T-cell subtypes that are particularly susceptible to certain classes of novel agents and would help physicians guide treatments. In the future, it would enable classifying patients according to their sensitivity to the treatment to find the most beneficial approaches with minimum side effects. This interview took place at the Lymphoma, Leukemia & Myeloma Congress 2021.