The 5th BelTox Workshop on Non-clinical Safety Assessment of Biopharmaceuticals took place on Thursday 11 May 2017 at Janssen Pharmaceuticals in Beerse (Belgium). This time, emphasis was on the interpretation of toxicological findings in animal studies with biopharmaceutical compounds and their relevance to man. The format of the workshop remained similar to the previous ones; i.e. lectures by international experts in the morning and the analysis and discussion of case studies in the afternoon. Of course this workshop also continued to provide ample opportunity for networking.