Ethical challenges in clinical studies with adaptive design in oncology

Novel immune therapies are increasingly based on the molecular differentiation of disease patterns. The related clinical studies are thus more often characterized by the so-called adaptive study designs (umbrella or basket studies including platform studies), which are continuously adjusted based on novel results. This paper analyses new study designs beyond the often-postulated need for regulation in order to identify ethical problems based on typical structural features and to—whenever possible—suggest solutions. To do so, it addresses the following topics: the relationship between social and scientific values of a study as well as aspects of the scientific validity of new forms of evidence; the inclusion of study subjects under the condition of relative uncertainty; specific challenges in the process of ethical approval, and ethical and practical challenges in the process of informing patients and receiving informed consent. Additionally, the topic of a potential risk–benefit assessment of such therapies is addressed.