There is common agreement that real-world trials are expected to extend existing knowledge on the efficacy and tolerability of a given agent in the target cohort. As results obtained in phase 3 studies can actually only be applied to a highly selected and frequently younger patient cohort with limited comorbidity in these trials, real-world studies permit to investigate the role of a given therapy in daily practice. Furthermore, adequately designed real-world trials may also provide answers to important clinical questions that can only be examined in clinical routine.