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By Reuters 
10h ago
By Julie Steenhuysen
Chicago – Data from clinical trials on two Covid-19 vaccines show that a variant of the coronavirus first identified in South Africa is declining its ability to protect against the disease, underscoring the need to vaccinate large numbers of people as closely as possible. as quickly as possible, the scientists said.
The vaccines from Novavax Inc and Johnson & Johnson were welcomed as important future weapons to curb deaths and hospitalizations in a pandemic that has infected more than 101 million people and claimed more than 2 million lives worldwide.
But they were significantly less effective in preventing Covid-19 in trial participants in South Africa, where the powerful new variant is widespread, compared to countries where this mutation is still rare, according to preliminary data released by the Business.
“Clearly, mutants have a diminishing effect on the efficacy of vaccines,” Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said in a briefing. “We can see that we will be challenged.”
Novavax on Thursday reported results from the mid-stage trial that showed its vaccine was 50% effective overall in preventing Covid-19 among people in South Africa.
That compared to late-stage results from the UK, in which the vaccine was up to 89.3% effective in preventing Covid-19.
On Friday, J&J said a single injection of its coronavirus vaccine was 66% effective overall in a massive trial across three continents.
But there were big differences by region. In the United States, where the South African variant was first reported this week, efficacy reached 72%, compared to just 57% in South Africa, where the new variant, known as B 1,351, accounted for 95% of the Covid-19 cases. reported at trial.
Another highly communicable variant first discovered in the UK and now in more than half of the US states, it has been less able to evade the efficacy of the vaccine than its South African counterpart.
However, the new findings raise questions about how highly effective vaccines from Pfizer Inc with its partner BioNTech and Moderna Inc will cope with the new variants. The two vaccines showed an efficacy of around 95% in trials conducted primarily in the United States before new versions of the virus were identified in other countries.
“It’s a different pandemic now,” said Dr. Dan Barouch, a researcher at the Beth Israel Deaconess Medical Center at Harvard University School of Medicine in Boston, who helped develop the J&J vaccine.
Barouch said there are now a wide variety of new variants circulating, including in Brazil, South Africa and even the United States, that are substantially resistant to vaccine-induced antibodies.
Pfizer chief executive Albert Bourla said there was “a high possibility” that emerging variants could eventually render the company’s vaccine ineffective.
“This is not the case yet … but I think it is very likely that one day that will happen,” Bourla told the World Economic Forum. The drugmaker is considering whether to modify its vaccine to defend against the South African variant.
‘PREVENT HOSPITALS FROM ENTERING CRISIS’
Experts said all four vaccines still have great value in their ability to reduce severe Covid-19.
“The end game is to stop death, keep hospitals from going into crisis, and all these vaccines, even against the South African variant, seem to do it substantially,” said Dr. Amesh Adalja, an infectious disease expert at the Johns Hopkins Center for the health security
For example, the J&J vaccine was 89% effective in preventing serious disease in South Africa.
J&J Chief Scientist Dr. Paul Stoffels said he suspects that a type of immune system reaction called the T-cell response plays a protective role and may help prevent serious disease.
“We knew to some extent, but it’s also better and very confirming that we can see that now in the clinic,” Stoffels said in an interview.
However, Fauci said the decreased efficacy rates underscore the need to closely monitor variants and accelerate vaccination efforts before new and even more dangerous mutations emerge.
“The best way to prevent further evolution of a virus is to prevent it from replicating,” Fauci said, “and that is achieved by vaccinating people as quickly as possible.”
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