Ethical considerations for epidemic vaccine trials

Abstract

Vaccines are a powerful measure to protect the health of individuals and to combat outbreaks such as the COVID-19 pandemic. An ethical dilemma arises when one effective vaccine has been successfully developed against an epidemic disease and researchers seek to test the efficacy of another vaccine for the same pathogen in clinical trials involving human subjects. On the one hand, there are compelling reasons why it would be unethical to trial a novel vaccine when an effective product exists already. First, it is a firm principle of medical ethics that an effective treatment or vaccine should not be withheld from patients if their life may depend on it. Second, since epidemic outbreaks often emerge in settings with less-resourced health systems, there is a pronounced risk that any trial withholding an effective vaccine would disproportionately affect the vulnerable populations that historically have been exploited for biomedical research. Third, clinical trials for novel vaccines may be at odds with efforts to control active outbreaks. On the other hand, it may be justified to conduct a trial for a candidate vaccine if it is expected to have certain advantages compared with the existing product. This essay discusses key factors for comparing vaccines against epidemic pathogens, including immunological, logistical and economic considerations. Alongside a case study of the development of vaccines for Ebola, the essay seeks to establish a general framework that should be expanded and populated by immunologists, epidemiologists, economists and bioethicists, and ultimately could be applied to the case of COVID-19 vaccines.

Promoting versatile vaccine development for emerging pandemics

“…Crucially, efforts to accelerate R&D must be complemented by other policies that can shorten the timeline between pathogen identification and population coverage, such as regulatory innovation to facilitate platform-based vaccine licensure, development of multivalent or universal vaccines, and efforts to ensure global, equitable vaccine access 53 . Additionally, to prepare for scenarios where conventional clinical trials may be unethical or infeasible, there is a need for regulatory innovation to facilitate potential emergency use authorisation on the basis of efficacy data from animal models and in some cases controlled human infection models 17 , 54 , 55 . Finally, realising the full potential of platform vaccines requires overcoming challenges in manufacturing and delivery, such as improving nucleic acid vaccine thermostability or creating cold chain storage solutions and developing devices for DNA vaccine electroporation.…”

Ethical dilemmas in the era of COVID-19

“…It is feared that such studies may be carried out in areas with less-resourced health systems, and hence there is a major concern that any trial withholding an efficient safe vaccine would probably affect the vulnerable populations who have been badly utilized with biomedical research in the past. [ 10 ]…”

“…Besides, the informed consent should be obtained in culturally and linguistically appropriate way. [ 10 ]…”

«Vísteme despacio que tengo prisa». Un análisis ético de la vacuna contra la COVID-19: fabricación, distribución y reticencia

“…Son estudios de doble estándar: investigaciones en países pobres que no serían éticamente aceptables en países ricos, bajo la premisa de que la rama placebo, que no recibe tratamiento, no estaría en desventaja por pertenecer a una población con carencias sanitarias (Hellmann et al, 2020). No hace falta una novela conspirativa de John Le Carré para descubrir que los riesgos de la experimentación suelen recaer en los más desfavorecidos (Monrad, 2020).…”

“…Si bien muchos aspectos relacionados con la COVID-19 se han tenido que improvisar, los conflictos éticos que pueden derivarse de la vacuna deben incorporarse a un debate en profundidad. Si algo sabemos de esta pandemia es que para conseguir acciones basadas en la colectividad no solo es necesario ofrecer datos sobre los que poner en marcha medidas, sino también argumentos, razones y, en definitiva, confianza en las instituciones de salud pública (Monrad, 2020).…”