Drug regulators and ethics: which GCP issues are also ethical issues?

Within the European Union (EU), good clinical practice (GCP) provides an ethical mandate to regulators; however, it is unclear what the content of that mandate is. By looking at the correspondence between GCP and ethical imperatives, we identify that the mandate is within the following: principles; benefit-risk ratio; scientific validity; results publication; informed consent; respect for participants; and special populations. There are also cases when regulations were ethical but were not pairable to an imperative, and when the former were stricter than the latter. Hence, we suggest closer cooperation between ethics committees and regulators to ensure that future versions of ethics guidelines cover the ethically relevant regulations that were not directly pairable to any imperative, and cooperation between GCP legislative bodies and ethics guideline-making bodies to resolve the discordant areas.