A healthcare worker administers the Novavax COVID-19 vaccine in the arm of a trial volunteer in Soweto, South Africa.
JOAO SILVA /The New York Times/ Redux
By Meredith Wadman, Jon Cohen
ScienceCOVID-19’s reporting is supported by the Pulitzer Center and the Heising-Simons Foundation.
The small biotechnology firm Novavax, once considered a dark horse in the COVID-19 vaccination battle, announced today that its candidate is delivering high efficiency – 89.3% – in a nuclear test in the UK where ‘ a new, highly transmissible variant of the pandemic coronavirus. responsible for more than half of the cases in people in the trial.
“These are spectacular results,” said Clive Dix, chairwoman of the UK Vaccine Taskforce, on the results of the trial, in which more than 15,000 people were enrolled. “This is an incredible achievement that will ensure that we can protect individuals in the UK and the rest of the world from this virus.”
Related
Interim results of a Novavax trial conducted separately in South Africa, in which another, worrying variant of SARS-CoV-2 makes the most infections, were disillusioning. Among 4160 participants who did not live with HIV, the effectiveness was 60.1%. This dropped to 49.4% when another 240 HIV-infected participants were included.
The South African coronavirus variant, called B.1.351 (and sometimes also called 501Y.V2), has three mutations in an important region of the virus’ vein protein. Recent test tube studies have suggested that these mutations may allow the stress to escape the antibodies caused by vaccines. But today’s results are the first evidence of people showing that this is so.
‘Now we know it there is a degree of loss of vaccine efficacy, up to about the level of 50% -60%, ‘says immunologist John Moore of Weill Cornell Medical College. “But it is NOT zero. And a year ago we would have decided with an effective vaccine of 50% -60%. ‘
Yet the South African trial has global implications. ‘The South African variant is a problem, and reducing its worldwide distribution is a priority, ”says Moore. “The more frequently it enters the U.S., the greater it is that it will expand.” As it were, the South African variant is being identified in the United States for the first time today. It has been found in two people in South Carolina with no travel history, suggesting it is already spreading in the community.
The Novavax vaccine uses a clearer technology than other COVID-19 vaccines already approved. It uses insect cells to cut out head lengths of the peak protein studying on the surface of SARS-COV-2 and enables it to invade the host cells. It is the first protein-based COVID-19 vaccine to report the results of a major clinical trial. Like the COVID-19 vaccines approved so far, it requires two doses. Another company, Janssen, is expected to announce the results tomorrow for a single dose of COVID-19 vaccine.
Overall, vaccine experts praised the results of both Novavax trials. Novavax has achieved a remarkable achievement. We need as many successful vaccines as possible, ”says Luciana Borio, a vaccination expert who is vice president of In-Q-Tel, a technology investment firm that invests in biosafety and other national security technologies.
Andrew Ward, a structural biologist at Scripps Research, who co-authored the foundation describing the structure of the Novavax vaccine, noted that compared to some other vaccines, ‘the cold chain requirements are much less stringent’ for this vaccine. , which should only be cooled to 2. to 8 degrees Celsius. “This is also good news for global vaccine efforts, especially in the third world and remote environment.”
Novavax has this month filed an application for approval by the vaccine regulator, called NVX-CoV2373, in the United Kingdom. It is said that it, including production at the Serum Institute of India, could make 2 billion doses of vaccine this year. The US approval will depend on the outcome of a recent 30,000-person trial in the US and Mexico. The trial attracted more than 16,000 participants in the first 30 days.
Although efficacy in South Africa was significantly lower than the 95% seen with mRNA vaccines from Moderna and Pfizer / BioNTech, South African scientists found good news, as the Novavax vaccine still has some efficacy against the variant het. ‘Although there is definitely an impact [on how much protection it confers], it may not be as bad as we all thought, ”says Lynn Morris, who heads the National Institute of Communicable Diseases in South Africa.
For the interim analysis of the South African trial, in which 44 infections were recorded from last September to mid-January, 15 infections occurred among vaccinated participants and 29 infections among placebo recipients. Of the successive viruses, 25 of 27 or 92.6% showed infection with the new B.1.351 variant.
Novavax says work is underway to develop a divalent vaccine that will attack the South African variant and others. Shabir Madhi, dean of the medical school at the University of the Witwatersrand and the chief investigator of the trial in South Africa, told reporters today that the work will possibly come to fruition within a few months.
South Africa has had an explosion of affairs since November. The new data suggest that this may be due in part to people who had COVID-19 recovered earlier in the pandemic and then became infected with the new variant again. This suggests that the variant may put an end to natural immunity, just as it did to some extent around the Novavax vaccine.
In the placebo group of the study, 30% were infected with SARS-CoV-2 before the study; the participants had the same COVID-19 rate during the trial as those who had never been infected before. Madhi calls these numbers ‘really worrying’.
“We would expect a large percentage of the population to develop immunity at first exposure,” he told reporters. ‘Unfortunately, infections with the earlier variants of the virus in South Africa do not protect against COVID-19 disease. Whether it has some value in terms of protection against serious diseases or deaths remains unknown. ”
The British and South African studies were not large enough to determine the impact of the vaccine on serious diseases. But to date, all COVID-19 vaccination trials – whether they had 50% or 95% against a mild illness – had at least 95% against serious illnesses.
Larger studies on the Novavax vaccine, such as one currently underway in the United States, could reveal its impact on serious diseases, Madhi said. “Based on experience with our respiratory vaccines, these vaccines usually work better against serious diseases.”
Until now, South Africa has not used any COVID-19 vaccine. Yesterday, the country granted emergency use for a COVID-19 vaccine made by AstraZeneca-Oxford. He plans to receive his first 1.5 million doses on Monday to vaccinate health workers.
Glenda Gray, the President and CEO of the South African Medical Research Council, warns that the impact of B.1.135 on the Novavax vaccine could be a harbinger of other vaccines. “As the new variants begin to circulate, we can see declining vaccine efficiencies in other vaccines currently being rolled out worldwide,” she says.
Madhi says: ‘SARS-CoV-2 taught us … to be humble and never to guess [the abilities of] the virus. “