Covid-19, the WHO, and the apparent collapse of traditional medical research ethics.

On January 14, 2021, a WHO Ad Hoc expert group published an article in the highly influential The New England Journal of Medicine, titled: "Placebo-Controlled Trials of Covid-19 Vaccines - Why We Still Need Them" justifying the use of placebo in further trials of Covid-19 vaccines, even after purported efficacious vaccines have become available. Medical research involving human beings ought to conform strictly to principles, rules and procedures established since the Nuremberg Code (1947), especially as elaborated in the Declaration of Helsinki (2013) and the WHO/CIOMS Guidelines (2016). The NEJM article forms part of an observable trend of moral backsliding that needs to be recorded. In this paper, considering traditional medical research ethics under the impact of the Covid-19 pandemic and its ramifications and effects, and with a particular focus on the highly vulnerable populations and countries of sub-Saharan Africa, I make some relevant remarks. My arguments here are anchored in my observations as a moral philosopher though limited by my lack of expertise in any of the branches of medical science.

Ethical limits to placebo use and access to Covid-19 vaccines as a human right.

The world is currently facing another severe pandemic, Covid-19, just four decades after the start of AIDS, and the still increasing incidence of HIV infection continues to be one of the greatest global health challenges. The way the latter was confronted is of fundamental importance for a serious discussion on global health, ethics and human rights, and this experience could and can still be applied to Covid-19. The Covid-19 pandemic has specific characteristics and these will be discussed, in relation to vaccine research and especially to the global right to equal access to products proven to be safe and effective. The article focusses primarily on issues related to Covid-19 vaccines, especially the appropriate use and limits on placebo, the right to post-trial access to placebo arm participants, and the use of an active control for subsequent Phase-3 trials after the approval of other safe and efficacious vaccines. Most importantly, it will emphasise that access to Covid-19 vaccines is a human right, which presupposes the establishment of appropriate ethical standards to ensure universal, equal, and affordable access to healthcare and to vaccines for all, and the imperative need for suspension of patents for products developed for Covid-19. It will consider the role of social determinants that contribute to the severity of Covid-19 and that must be addressed to effectively curb the current syndemic.

Placebo in new Covid-19 vaccine trials: data quality prioritised over participants' rights.

The WHO Ad Hoc Expert Group on the Next Steps for Covid-19 Vaccine Evaluation makes recommendations on the use of placebo controlled trials in ongoing and future Covid-19 vaccine research. These recommendations unequivocally prioritise data quality over participants' rights and safety. Participants in trials of vaccines which have received emergency use listing or authorisation would be refused available vaccines. Placebo-controlled trials that would be impossible to conduct in rich countries would be permitted in poor countries. If these suggestions are implemented, the major beneficiary will be the vaccine industry.

Trials for second generation Covid-19 vaccines: Revisiting the debate over placebo use in developing country clinical trials.

This article compares the current debate over the use of placebos in developing country clinical trials of second generation Covid-19 vaccines with the debates over previous paradigmatic cases raising similar issues. Compared to the earlier zidovudine and Surfaxin trials, Covid-19 vaccine trials are likely to confer lower risk to placebo groups and to offer a greater number and variety of alternative study designs. However, turning to the developing world to conduct studies that would be unacceptable in developed countries, simply on the ground that Covid-19 vaccines are generally unavailable in developing countries, is not ethically justifiable. This is so whether the justification is rooted in total absence of vaccine in a given country or in developing country vaccine prioritisation practices, because at root both derive from economic, not scientific conditions. However, the advent of variants that may create genuine uncertainty as to comparator vaccine effectiveness could justify a placebo control, depending on vaccine characteristics, variant prevalence, the degree of variant resistance, and the acceptability of immune-bridging studies. These factors must be considered together in the necessary case-by-case assessment of the ethical justification for any proposed trial.

Placebo control in Covid-19 trials: A missed opportunity for international guidance.

Vaccines preventing Covid-19 have been approved in several countries. Is it still ethically acceptable to use placebo controls during the development of other vaccine options? If two of the most influential international guidelines of biomedical research are consulted, the Declaration of Helsinki and the CIOMS-guidelines, the answer is "no". We discuss the implications for ongoing vaccine research, and how placebo controls might be justified nevertheless. However, the ethical conflict remains highly problematic. We suggest that such ethical dilemmas should be avoided in the future by the introduction of a new system of global governance. Once vaccines are approved, a global regulation should oblige producers to provide the necessary amount of vaccine doses for the control groups of ongoing vaccine research.

The continued use of placebo arms in COVID-19 vaccine trials does not adequately protect the well-being of participants.

Covid-19 vaccines are a critical tool for controlling the pandemic. While safe and effective vaccines have been developed, research is expected to continue for many years regarding the optimal implementation of existing vaccines in specific settings, and the development of second-generation vaccines that may offer advantages in terms of either efficacy or ease of implementation. Given this context, some commentators have argued that new Covid vaccine trials should be able to use placebo controls, and that existing studies should be able to continue with blinded participants in order to collect high quality, unbiased data. Using international ethics guidance documents, this paper argues against placebo controls, given the existence of proven effective interventions, and against protracted blinding once safety and efficacy milestones have been met. Instead, it advocates for study designs that allow for direct comparison between approved and experimental vaccines, which facilitates both data collection and greater access to vaccines.

"No" to placebo-controlled trials of Covid-19 vaccines.

Recently the WHO Ad Hoc Expert Group proposed that it is ethical to continue placebo-controlled Covid-19 vaccine trials in countries where vaccines are not available even if this vaccine is marketed and being used elsewhere. The reason for this proposal is the usual scientific argument claiming that these trials are the most efficient method to obtain reliable results, and individuals in these countries will continue to get the local standard of care, meaning no vaccination, and thus participants are not being left worse off. We refute this argument on two counts. First the global equity and justice issue, that the scarcity of vaccines in most countries is created by the rich nations that have hoarded vaccines. Second, the science versus research ethics issue, that there are valid scientific methods like non-inferiority trials which can give reliable results, and that applying a standard of care imposed by rich nations is both unethical and possibly exploitative. Thus, we feel that the WHO Ad Hoc Expert Group is wrong in proposing to continue placebo-controlled Covid-19 vaccine trials.

Testing vaccines in the time of Covid: The changing landscape.

The initial trials of SARS-CoV-2 vaccines were randomised control trials (RCT) with a placebo as control. The use of a placebo was ethically justified because, as with any new and emerging infectious disease, there was no known vaccine. There are now at least eight vaccines that have been shown to be effective and approved for emergency use, so the use of a placebo in the control group is no longer ethically justified. This article discusses why ethical guidelines should be continually evaluated in a changing landscape and why trust is so important.

Placebo-controlled trials of Covid-19 vaccines - Are they still ethical?

A World Health Organization (WHO) Ad Hoc Expert Group on the Next Steps for Covid-19 Vaccine Evaluation recently recommended placebo-controlled trials (PCT) of Covid-19 vaccines. PCTs are ethically acceptable when there is no proven effective and safe treatment for a certain condition. However, there are already some vaccines that have been approved and which have high levels of efficacy and safety. Any new vaccine under development must be tested against the most effective vaccines available. PCTs go against the participants' best interests, by putting them in a position of disadvantage while taking part in a trial, compared with people who are not in the trial and who could get vaccinated. Particularly in high-income countries, many people are getting vaccinated. This means that, following a recent trend in clinical trials, PCTs would have to be conducted in low- and middle-income countries, where there a number of advantages for drug companies, but where fatality rates of Covid-19 are, in many cases, much higher. For this and other reasons having to do with equal rights, participants in control groups should be protected with the most effective vaccines available.

Problematic Covid-19 vaccine trials in times of vaccine nationalism.

Thanks to an impressive R&D effort, three vaccines for Covid-19 have been conditionally approved by stringent regulators as of February 2021, and sixteen have entered the WHO evaluation process. However, they all need to keep on being evaluated in clinical trials. The WHO Ad Hoc Expert Group on the Next Steps for Covid-19 Vaccine suggested that countries with limited or no access to an effective vaccine could ethically permit placebo-controlled trials, even if effective vaccines were already being marketed elsewhere. Here, I argue that inclusion in a placebo-controlled trial is ethically sound for those who would be in any case ineligible for vaccination outside the trial, and as long as the access to the vaccine outside the trial depends on a transparent and just allocation framework. Conversely, carrying out placebo-controlled studies in countries where vaccines are not (or are insufficiently) available because of unequal global allocation, would be unethical, as an ethical strategy cannot be built on an unethical premise.