South African Volunteers Join Oxford COVID-19 Vaccine Trial
A COVID-19 vaccine may be the only way to halt the coronavirus

24 June 2020 (Cape Town, South Africa) – From today, South Africans volunteers will join thousands of people in the UK, US and Brazil in testing a COVID-19 candidate vaccine developed by the Oxford Jenner Institute.

The South African Ox1Cov-19 Vaccine VIDA-Trial will involve 2,000 people, including 50 people living with HIV, in a collaboration between Wits University, the University of Oxford and the Oxford Jenner Institute.

The candidate vaccine is currently being tested for safety on 4,000 Britons, with another 10,000 people expected to join the trial by the end of July as it expands to test efficacy. Within the next few weeks, 7,000 Brazilians and 10,000 US citizens will also start testing the candidate vaccine.

“This is a landmark moment for South Africa and Africa at this stage of the COVID-19 pandemic. As we enter winter in South Africa and pressure increases on public hospitals, now more than ever we need a vaccine to prevent infection by COVID-19,” said trial leader Shabir Madhi, and Professor of Vaccinology at Wits University.

Madhi said that Johannesburg residents had responded with enthusiasm to the call for volunteers: “We sent messages out via community groups and within three days, over 1000 people had come to our clinics wanting to know more about how they could be involved.”

Shabir Madhi, Principal Investigator of the first Covid-19 vaccine trial in South Africa

The study is being undertaken in urban areas where the risk of SARS-CoV2 infection is high. South Africa accounts for over half of Africa’s COVID-19 cases and this week reached 100,000 cases.

The double-blinded randomised control trial is expected to last a year, but Madhi said that “once 42 people have tested positive for the virus, we will know whether it will work or not”, adding that the vaccine would need to show at least 60% efficacy to be viable.

Madhi added that genetic information, including blood type, would be collected from volunteers to see whether this had any impact on infection.

Participants will be given an E-diary to record any symptoms experienced for seven days after receiving the vaccine. They will also record if they feel unwell for the following three weeks.

Following vaccination, participants will attend a series of follow-up visits. During these visits, researchers will review the completed diaries and take blood samples to assess their immune response to the vaccine.

If participants develop COVID-19 symptoms during the study, a member of the clinical team will assess them for infection and, if they become particularly unwell, they will be helped to get hospital care.

The technical name of the vaccine is ChAdOx1 nCoV-19, as it is made from an adenovirus called ChAdOx1. The vaccine contains genetic material that codes for the spike glycoprotein expressed on the surface of the SARS-CoV-2 virus.

The virus that causes COVID-19 uses this spike protein to bind to ACE2 receptors on human cells. Researchers have already shown that antibodies produced against sections of the spike protein after natural infection are able to neutralize the virus when tested in the laboratory.

By vaccinating volunteers with ChAdOx1 nCoV-19, scientists hope to make the human body recognise and develop an immune response to the spike glycoprotein that will help stop the SARS-CoV-2 virus from entering human cells and causing COVID-19.

The South African study has been approved by the South African Health Products Regulatory Authority (SAHPRA) and the Human Research Ethics Committee of the University of the Witwatersrand.

Helen Rees, Chair of South African Health Products Regulatory Authority

“It is essential that vaccine studies are performed in southern hemisphere countries, including in the African region, concurrently with studies in northern hemisphere countries,” says Professor Helen Rees, Chair of SAHPRA.

“This allows evaluation of the efficacy and safety of candidate vaccines to be assessed in a global context to see whether they work across different populations.”

However, Rees warned that access to any vaccine would be highly competitive and a vaccine might have to be rationed initially with health workers possibly being the first to be vaccinated.

There are currently over 260 candidate COVID-19 vaccines in development around the world. The ChAdOx1-Cov19 vaccine is one of only five vaccines that are currently in the clinical development phase in humans, with the studies mainly being done in China, USA, UK, Australia and Europe.

Image Credits: Kerry Cullinan , University of the Witwatersrand, University of the Witwatersrand.