Sex partners as bystanders in HIV prevention trials: Two test cases for research ethics

Research involving human subjects can impose risk on some 'bystanders'- people who are not themselves research subjects but whom the study may affect. We examine the consequences of research for a particular category of bystanders - research subjects' sex partners - in trials testing interventions to reduce (1) HIV transmission (HIV treatment-as-prevention trials) and (2) HIV acquisition (HIV pre-exposure prophylaxis trials). Both types of trials provide useful test cases for assessing whether bystanders to research deserve special consideration in ethics reviews, and potentially some of the benefits and protections that research subjects receive. In HIV treatment-as-prevention trials, there are two groups of people who are alike in many important respects but treated very differently by research ethics: research subjects who contribute data on the primary endpoint of the trial (because some of them have sex with the people receiving the treatment conditions of the trials) - and bystanders who are not enrolled in the trials but who could have contributed primary endpoint data in the same way as the first group. In pre-exposure trials, the sex partners of people participating in pre-exposure prophylaxis trials are bystanders, even though they are necessary for the success of the trial. Research subjects' autonomy is fiercely protected by trial enrolment processes. Bystanders, by contrast, often have no choice but to be affected by the study, because of their relationship to a research subject. In HIV prevention trials, standing by can come with important risks, including the same ones on which the success of the research hinges. It is thus important to consider the ethical obligations to protect bystanders, and the related procedural responsibilities.