Notwithstanding the success of conventional field trials for vaccines against COVID-19, human challenge trials that could obtain more information about these and about other vaccines and further strategies against it are about to start in the UK. One critique of COVID-19 HCTs is their distinct paucity of information on crucial population groups. For safety reasons, these HCTs will exclude candidate participants of advanced age or with comorbidities that worsen COVID-19, yet a vaccine should protect such populations. We turn this cliché (...) on its head. The truth is that either an HCT or a field trial has intrinsic generalisability limitations, that an HCT can expedite protection of high-risk participants even without challenging them with the virus, and that an important route to obtaining results generalisable to high-risk groups under either strategy is facilitated by HCTs. There are no data in this work. (shrink)

Despite their clearly demonstrated safety and effectiveness, approved vaccines against COVID-19 are commonly mistrusted. Nations should find and implement effective ways to boost vaccine confidence. But the implications for ethical vaccine development are less straightforward than some have assumed. Opponents of COVID-19 vaccine challenge trials, in particular, made speculative or empirically implausible warnings on this matter, some of which, if applied consistently, would have ruled out most COVID-19 vaccine trials and many non-pharmaceutical responses.

Conservative assumptions in medical ethics risk immense harms during a pandemic. Public health institutions and public discourse alike have repeatedly privileged inaction over aggressive medical interventions to address the pandemic, perversely increasing population-wide risks while claiming to be guided by ‘caution’. This puzzling disconnect between rhetoric and reality is suggestive of an underlying philosophical confusion. In this paper, I argue that we have been misled by status quo bias—exaggerating the moral significance of the risks inherent in medical interventions, while systematically (...) neglecting the risks inherent in the status quo prospect of an out-of-control pandemic. By coming to appreciate the possibility and significance of status quo risk, we will be better prepared to respond appropriately when the next pandemic strikes. (shrink)

In spring, summer and autumn 2020, one abiding argument against controlled human infection studies of SARS-CoV-2 vaccines has been their impact on local communities. Leading scientists and bioethicists expressed concern about undue usage of local residents’ direly needed scarce resources at a time of great need and even about their unintended infection. They recommended either avoiding CHI trials or engaging local communities before conducting any CHIs. Similar recommendations were not made for the alternative—standard phase III field trials of these same (...) vaccines. We argue that the health effects of CHI studies on local residents not participating in the study tend to be smaller and more positive than those of field trials. That is all the more so now that tested vaccines are being rolled out. Whether or not local community engagement is necessary for urgent vaccine studies in the pandemic, the case for its engagement is stronger prior to field trials than prior to CHI studies. (shrink)

In a recent article, Steel, Buchak and Eyal argue that current levels of uncertainty do not present a good reason to bar controlled human infection trials of COVID-19 vaccines from proceeding. We argue that their argumentation for this conclusion is flawed. SBE are mistaken about the effects which different forms of ignorance have on participants’ ability to provide valid informed consent. Decision-makers considering whether to allow such trials, we argue, must ultimately consider the likelihood that consent to participation in such (...) trials under current conditions would be valid, and whether this likelihood is high enough to permit such trials. This is a question that SBE completely ignore. We conclude that there indeed are valid concerns about conducting CHI trials given the current state of knowledge about COVID-19, concerns which SBE fail to address. (shrink)