At the 20th Congress of the European Hematology Association (EHA), Paolo Ghia, MD, PhD, of Università Vita-Salute San Raffaele, Milan, Italy, discusses the overall survival (OS) analysis adjusting for treatment effect after crossover in a phase 3 study evaluating the PI3K delta inhibitor, idelalisib, in combination with rituximab in patients with relapsed chronic lymphocytic leukemia (CLL).