At the International Workshop on Non-Hodgkin Lymphoma (iwNHL) 2015 meeting, John Gribben, MD, DSc, FRCPath, FRCP FMedSci, of Barts and The London School of Medicine and Dentistry, London, UK, discusses the efficacy and safety of idelalisib, a first-in-class selective oral inhibitor of phosphoinositide 3-kinase (PI3K) delta, for the treatment of patients with follicular lymphoma.