An exciting update on the 4-year follow-up of the RESPONSE Trial (NCT01243944) was given by Jean-Jacques Kiladjian, MD, PhD, of Saint-Louis Hospital & Paris Diderot University, Paris, France, at the American Society of Hematology (ASH) 2017 Annual Meeting and Exposition, held in Atlanta, GA. The RESPONSE trial compared the efficacy and safety of ruxolitinib vs. the best available therapy in patients with hydroxyurea-intolerant/resistant polycythemia vera (PV). Now, after conducting a 4-year follow-up on the study, Prof. Kiladijan discusses the results and the next steps.