Do we really know how many clinical trials are conducted ethically? Why research ethics committee review practices need to be strengthened and initial steps we could take to strengthen them.

Research Ethics Committees (RECs) play a critical gatekeeping role in clinical trials. This role is meant to ensure that only those trials that meet certain ethical thresholds proceed through their gate. Two of these thresholds are that the potential benefits of trials are reasonable in relation to risks and that trials are capable of producing a requisite amount of social value. While one ought not expect perfect execution by RECs of their gatekeeping role, one should expect routine success in it. This article reviews a range of evidence showing that substantial numbers of ethically tainted trials are receiving REC approvals. Many of the trials are early phase trials that evidence shows have benefits that may not be reasonable compared with their risks and many others are later trials that evidence shows may lack sufficient social value. The evidence pertains to such matters as methodologically inadequate preclinical studies incapable of supporting the inferences that REC members must make about the prospects for potential benefit needed to offset the risks in early phase trials and sponsorship bias that can cause improperly designed, conducted, analysed and reported later phase trials. The analysis of the evidence makes clear that REC practices need to be strengthened if they are to adequately fulfil their gatekeeping role. The article also explores options that RECs could use in order to improve their gatekeeping function.