Robin Foà, MD from the Sapienza University, Rome, Italy discusses the question of how the trials on biosimilars should be run and what needs to be done for biosimilars to get approved. According to Prof. Foà, this is a difficult question and he points out that the European Medicines Agency (EMA) has stated that extrapolation is acceptable. He talks about the importance of demonstrating the safety and efficacy of biosimilars and discusses when extrapolation may be acceptable. Prof. Foà further argues that it is unrealistic to repeat all trials. Recorded at the European Hematology Association (EHA) 2016 Annual Congress in Copenhagen, Denmark.