New data show that the virus variant in South Africa has an effect on the vaccine

CHICAGO (Reuters) – Clinical trials of two COVID-19 vaccines show that a variant of coronavirus first identified in South Africa is reducing their ability to protect against the disease, stressing the need to vaccinate as many people as possible. said the scientists.

Vaccines from Novavax Inc. and Johnson & Johnson have been hailed as important future weapons in fighting deaths and hospitalizations in a pandemic that has infected more than 101 million people and killed more than 2 million people worldwide.

But they were significantly less effective in preventing COVID-19 in study participants in South Africa, where the new strong variant is widespread, compared to countries where this mutation is still rare, according to preliminary data published by companies.

“Clearly, mutants have a diminishing effect on vaccine efficacy,” 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 reported the results of its mid-stage study on Thursday, which showed that its vaccine was 50% overall effective in preventing COVID-19 among people in South Africa.

This is compared to the results of the late stage in the United Kingdom, where the vaccine was up to 89.3% effective in preventing COVID-19.

On Friday, J&J said a single stroke of its coronavirus vaccine was 66% effective overall in a massive study on three continents.

But there were big differences depending on the region. In the United States, where the South African variant was first reported this week, the effectiveness reached 72%, compared to only 57% in South Africa, where the new variant, known as B 1,351, accounted for 95%. of the COVID-19 cases reported in the trial.

Another highly transmissible variant first discovered in the UK and now in more than half of the US states has been less able to evade the vaccine’s effectiveness than its South African counterpart.

The new findings, however, raise questions about how highly effective vaccines from Pfizer Inc. with partner BioNTech and Moderna Inc. will relate to the new variants. The two vaccines showed approximately 95% efficacy in studies conducted mainly 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 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 CEO Albert Bourla said there was a “high possibility” that the emerging options would eventually make the company’s vaccine ineffective.

“It’s not the case yet … but I think it’s very likely that one day it will happen,” Bourla told the World Economic Forum. The manufacturer of the medicine is considering whether the vaccine should be modified to protect against the South African variant.

“STOP HOSPITALS FROM ENTERING THE CRISIS”

Experts said all four vaccines are still of great value in their ability to reduce COVID-19 severely.

“The ultimate game is to stop death, to stop hospitals from going into crisis – and all these vaccines, even against the South African variant, seem to do this substantially,” said Dr. Amesh Adalja, an expert in infectious diseases at the Johns Hopkins Center for Health Security

For example, the J&J vaccine has been 89% effective in preventing severe disease in South Africa.

J&J Scientific Director Dr. Paul Stoffels said he suspects that a type of immune system reaction called a T-cell response plays a protective role and may help prevent severe disease.

“I knew that to some extent, but it’s also better and very confirmatory that we can see that now in the clinic,” Stoffels said in an interview.

However, Fauci said the low efficacy rates underscore the need to closely monitor variations and accelerate vaccination efforts before new and even more dangerous mutations occur.

“The best way to prevent the further evolution of a virus is to prevent its reproduction,” Fauci said, “and do this by vaccinating people as soon as possible.”