“What’s important in terms of a vaccine right now is preventing people from getting severely ill and dying.”
Researchers involved in the Novavax vaccine trial at the Wits-Vaccines and Infectious Diseases Analytics Research Unit (VIDA), say the vaccine can provide protection against the South African variant of the coronavirus.
“The Novavax vaccine is the first that provides objective scientific evidence that it can protect people against the variant virus circulating in South Africa,” said Prof Shabir Madhi, lead researcher of the South African Novavax trial, in a podcast released by The Conversation on February 1.
The results of the SA phase 2b trial, which were released on January 28, show 60% efficacy in people not living with HIV and 49% for people who are HIV-positive, although the latter was a smaller sample group.
“The 60% efficacy reported for the Novavax vaccine needs to be benchmarked against the World Health Organisation’s and other regulatory authorities’ criteria, that any covid-19 vaccine with at least 50% efficacy and which protects for at least six months would be considered to be useful from a health perspective,” Madhi said.
The vaccine, known as NVX-CoV2373, was developed by US-based company, Novavax, and is protein-based. It is different from the messenger RNA vaccines developed by companies such as Pfizer and Moderna or the viral-vector vaccine produced by AstraZeneca.
“[Novavax] is called a protein-based vaccine. What this means is that the spike protein (coronavirus has spikes on it) has been made in a laboratory and that is being used as the vaccine,” Professor Lynn Morris, head of HIV virology at the National Institute for Communicable Diseases, told Wits Vuvuzela.
According to Morris, “By making the protein in the lab scientists are basically tricking the body into thinking that it is seeing the live virus when in fact the body is only seeing part of it.”
The vaccine stimulates the body’s immune system to potentially provide immunity or less severe illness in the case of an actual infection. “That’s how vaccines work. The body recognises these foreign viruses and bacteria that are trying to infect us and we make an immune response to it. The major response is an antibody response,” Morris said.
She added, “What’s important in terms of a vaccine right now is preventing people from getting severely ill and dying, and that’s different from getting infected because you can get infected and still have a moderate illness. If a vaccine can prevent severe illness, that’s important.”
As the Novavax trial enters phase 3, there is no guarantee that the vaccine will be made available to South Africans should the trials be successful.
“I’m uncertain whether the South African government has as yet engaged with Novavax, which is a small biotech company in the US. However, Novavax has partnered with the Serum Institute of India to produce the Novavax vaccine. It would be important for the government to engage with the Serum Institute of India on accessing this effective vaccine,” Madhi said.
FEATURED IMAGE: Chris Hani Baragwanath Academic Hospital in Soweto, where the Wits-VIDA research site is located. Photo: Khuleko Siwele
- Wits Vuvuzela, HEALTH FEATURE: A rapidly produced vaccine can still be trusted, September 2020.
- Wits Vuvuzela, New app to support doctors on the covid-19 frontline, August 2020.