Novavax Inc. said on Thursday that its COVID-19 vaccine appears 89% effective based on the first findings of a British study and that it also appears to work – albeit not so well – against new mutant versions of the virus circulating in that country and in South Africa .
The announcement comes amid concerns over whether a variety of vaccines being launched around the world will be strong enough to protect against worrying new variants – and how the world desperately needs new types of injections to increase scarce supplies.
The study of 15,000 people in Britain is still ongoing. But a provisional analysis found that 62 participants so far have been diagnosed with COVID-19 – only six of them in the group that received the vaccine and the rest who received false injections.
The infections occurred at a time when Britain was experiencing a jump in COVID-19 caused by a more contagious variant. A preliminary analysis found that more than half of the study participants who were infected had the mutated version. The numbers are very small, but Novavax said they suggest the vaccine is almost 96% effective against the older coronavirus and almost 86% effective against the new variant. The results are based on cases that occurred at least one week after the second dose.
“Both figures are dramatic demonstrations of our vaccine’s ability to develop a very potent immune response,” said Novavax CEO Stanley Erck in a liaison with investors late on Thursday.
Scientists are even more concerned about a variant first discovered in South Africa that carries different mutations. The results of a smaller Novavax study in that country suggest that the vaccine works, but not as well as against the British variant.
The South African study included some volunteers with HIV. Among HIV negative volunteers, the vaccine appears 60% effective. Including volunteers with HIV, overall protection was 49%, the company said. While genetic testing is still ongoing, so far about 90% of the COVID-19 diseases found in the South African study appear due to the new mutant.
“These are good results. There are reasons to be optimistic ”about the 60% effectiveness, said Glenda Gray, head of the South African Medical Research Council. Even against the new variant, which now causes more than 90% of new cases in that country,“ we are still seeing the effectiveness of the vaccine, ”she said.
More worrying is what the study showed on an entirely different issue – the chances of people getting COVID-19 a second time, said South African study leader Shabir Madhi of the University of Witwatersrand in Johannesburg. The tests suggested that almost a third of the study participants had already been infected, but the rates of new infections in the placebo group were similar.
“The previous infection with early variants of the virus in South Africa does not protect” against infection with the new one, he said. “There doesn’t seem to be any derivative protection.”
Novavax said it needs some additional data before it can get British authorization to use the vaccine sometime in the next month or so. A larger study in the US and Mexico involved just over half of the 30,000 volunteers needed. Novavax said it is not clear whether the Food and Drug Administration will need data from this study as well, before deciding whether to allow use in the United States.
In the meantime, it is beginning to develop a version of the vaccine that could more specifically target the mutations found in South Africa, should health authorities eventually decide that an updated dosage is needed.
COVID-19 vaccines train the body to recognize the new coronavirus, especially the spike protein that surrounds it. But the Novavax candidate is made differently from the first shots used. Called a recombinant protein vaccine, the Maryland company uses genetic engineering to grow harmless copies of the peak coronavirus protein in insect cells. Scientists extract and purify the protein and then mix it with a chemical that boosts the immune system.
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AP medical writer Marilynn Marchione contributed.
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