/ 18 April 2020

Covid-19 vaccine testing in vulnerable populations must be guided by ethics

Coronavirus Sample Testing At Mgh
Swab duty: Test samples are delivered to a laboratory in Boston. In South Africa, labs are racing to catch up on the large backlog distorting the national Covid-19 picture. (Jessica Rinaldi/Boston Globe via Getty Images)

COMMENT

Recent comments made by two leading French doctors rightly sparked international outrage. During a live television interview, Jean-Paul Mira and Camille Locht suggested that a potential vaccine for Covid-19 be tested in Africa, where “they have no masks, treatments or resuscitation”. In response, the World Health Organisation (WHO) declared that “Africa will not be a testing ground for any vaccine”. 

As the Covid-19 pandemic rages on, racial disparities in outcomes become obvious; and, as scientists race to find effective therapies, vaccines are increasingly being considered as a potential solution to the crisis. 

A vaccine is a biological product that is administered to induce immunity to a particular disease — a process called vaccination or immunisation. This process is inherently beneficial, but it can result in harm if not properly conducted. Human trials are essential in determining the safety of any vaccine. But how do we select the candidates for a vaccine test? 

When properly analysed, the comments made by Mira and Locht reveal the underlying link between poverty and disease. Globally, poor populations tend to be underrepresented in major scientific studies. Recently, the WHO, currently led by an African, expressed fear that the coronavirus pandemic could spread to countries with “weaker health systems”, many of which are in Africa. A weak health system is closely tied to a struggling economy. It is this narrative of poverty and disease in vulnerable populations that fuels ideas about questionable vaccine trials. 

Public outcry against the infamous Tuskegee syphilis study and similar human experiments resulted in formal ethical documents such as the Nuremberg Code and the Declaration of Helsinki. Those instruments aimed to protect research subjects from harm by ensuring informed consent and voluntary participation. 

The fallouts from unethical experiments are persistent. They include distrust of public health officials and poor participation in research studies by members of vulnerable populations. 

In Nigeria, the United States pharmaceutical giant Pfizer carried out an unauthorised clinical trial of the antibiotic trovafloxacin (Trovan). The experiment compared Trovan with the standard treatment (ceftriaxone) during epidemic meningitis affecting the northern part of the country in 1996. Five of 100 children given Trovan died, and six of 100 who received a substantially reduced dose of the standard drug died. A $75-million out-of-court settlement was eventually agreed in 2009 after the company was found guilty. 

Although vaccine trials for endemic diseases such as malaria and HIV are beneficial, especially for populations ravaged by disease, there is a need for proper regulation and supervision to prevent exploitation and harm. Key ethical principles should be adhered to. These include scientific validity, social value, independent review, fair subject selection, favourable risk-to-benefit ratio and informed consent, as well as respect for participants and communities. The role of a collaborative partnership must be emphasised to all concerned. 

Clinical trials still represent the gold standard in testing the safety and efficacy of new and existing treatments. However, developing regions, including sub-Saharan Africa, remain underrepresented in pharmaceutical-industry-sponsored trials for several reasons, including the fear of corruption and unethical behaviour. Corruption, whether actual or perceived, is one of many issues that have precluded the implementation of more industry-sponsored clinical trials in this region. 

Africans, and indeed other vulnerable populations, must be recognised as partners rather than pawns. The second-most populous continent deserves better representation in key epidemiological studies. 

Covid-19 vaccines are best studied in populations that are worst affected by the outbreak. The French doctors in question need intensive re-education after they publicly apologise and retract their offensive statements. The future of vaccine testing in vulnerable populations — its success or failure — is entirely up to us all.