Guest Post: Danielle Bromwich and Joseph Millum
Paper: Informed Consent to HIV Research
Special Issue: The benefit/risk ratio challenge in clinical research, and the case of HIV cure
A cure for HIV would be tremendously valuable. Approximately 37 million people worldwide are HIV-positive and 15 million are currently on antiretroviral therapy. Until recently it was assumed that this therapy would be the extent of HIV treatment and that those with access to it would need to take their drugs for life. But what once seemed impossible is now in early phase clinical trials: interventions designed to completely eradicate HIV from the immune system.
Excitement surrounding these “HIV cure” studies is tempered by ethical concern. They require participants to come off their antiretroviral therapy and undergo highly risky interventions using gene transfers or stem cell therapy. These are currently proof of concept studies—no one expects the participants to be cured. Their purpose is to provide essential information about safety and pharmacokinetics, but in doing so they expose participants to high risks with little prospect of direct benefit.
If we could be confident that participants understood their trials’ true risk-benefit ratio, these high risks might be less troubling. But such confidence would be misplaced. Decades of data show poor comprehension of risk among participants in clinical trials. The fact that HIV is still a stigmatized condition amplifies this concern. Potential participants may be desperate to be rid of their disease and so downplay the risks and exaggerate the potential benefits. Understandably, HIV cure researchers and research ethics committees are worried. What should they do with a patient-participant who wants to come off his medication and receive a high-risk experimental intervention because he thinks that he’ll be “the one” who is cured?
Informed consent is generally thought to be one key protection for participants enrolled in risky studies. The standard view of informed consent says that valid consent requires the person giving consent to understand the risks and benefits of study participation. According to this view, someone who seriously misunderstands the study’s true risk-benefit ratio can be excluded on the grounds that he has not given valid consent to study participation.
In a recent paper, part of a special collection on HIV cure research in the Journal of Medical Ethics, we analyze a range of concerns about informed consent for HIV cure trials.
Against the standard view on understanding, we argue that it is not necessary to understand risks in order to give valid consent. In fact, if you take this widely accepted view seriously, you end up committed to the conclusion that it is never possible to give valid consent to medical research participation. Such a view would be absurd.
If understanding all the risks is not necessary for valid informed consent, does that mean that researchers and research ethics committees should be unconcerned about whether the people enrolling in HIV cure studies understand? Not at all. This case illuminates a further function of the informed consent process that explains, without absurdity, why understanding matters.
The primary goal of the process is to obtain valid consent. This is an ethical requirement of most studies, and proceeding without it often involves serious rights violations. But there’s an important secondary goal. In disclosing information clearly and carefully and in discussing the study with participants, we aim to facilitate good decision-making—helping participants make decisions that are consistent with and promote their values and preferences. Good decision-making is an ethical aspiration. While we cannot force a competent adult to do what she should, we know that she is more likely to make a good decision about study enrolment if she understands the information that is relevant to that decision. We respect autonomy by getting valid consent; we enhance autonomy by helping people make good decisions.
Given the unfavorable risk-benefit ratio they face, testing potential participants’ comprehension of facts like risks and benefits would be a worthwhile check on whether they are making a decision that is genuinely consistent with their values and preferences. Such checks might seem paternalistic if people do not need to understand risks in order to exercise their autonomy rights. But patients whose HIV is controlled on medication do not have a right to enroll in “cure” research, and so delaying or refusing to enroll on these grounds does not violate their rights. If a participant is seriously confused, researchers can supplement the informed consent process with an extended one-on-one discussion, retesting understanding after this intervention. This would no doubt add to the researcher’s workload. But given the low numbers of participants enrolled in early phase trials, it is unlikely to be too burdensome. The benefits to participants are worth it.