R. Donald Harvey, PharmD, BCOP, FCCP, FHOPA, from the Winship Cancer Institute, Atlanta, GA, gives a pharmacists perspective on the challenges of using biomarkers in immunotherapy. Using PD-1 and PD-L1 as examples, Dr Harvey discusses the challenge in interpreting biomarker results to make clinical decisions and identify which patients will benefit from a given therapy., Dr Harvey shares insights from the audience discussions on the subject at the 2018 Hematology/Oncology Pharmacy Association (HOPA) Annual Conference, held in Denver, CO.