Sen (Mars) Xu is a PhD student in the Center for Drug Safety and Policy Research of Xi'an Jiaotong University. His research focuses on pharmaceutical policy, drug utilization, and pharmacoeconomic evaluation. During his PhD study, he participated in assessment of non-prescription antibiotic dispensing at community pharmacies in China, evaluation on the prices and availability of essential medicines in China, and study on the current situation of drug supply in China. He will conduct national-level drug utilization research on antibacterial, anticancer, antidiabetic and antihypertensive drugs. Sen’s PhD subject is surveillance of antibiotic utilization in China and the evaluation of national action plan. Drs. Dennis Ross-Degnan and Anita Wagner will be his mentors in the Division of Health Policy and Insurance Research (HPI).