A Dose of J.&J. Study Suggests Vaccine Is Ineffective Against Delta

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The coronavirus vaccine made by Johnson & Johnson is much less effective against Delta and Lambda variants than the original virus. new work It was posted online on Tuesday.

The findings show that 13 million people were supported by J.&J. The authors said the vaccine may need to receive a second dose – ideally one of the mRNA vaccines made by Pfizer-BioNTech or Moderna.

But the results contradict those from the following. smaller studies A single dose of the vaccine, released earlier this month by Johnson & Johnson effective against variant even eight months after vaccination.

The new study has not yet undergone peer-reviewed or published in a scientific journal and was based on laboratory experiments. However, it is consistent with observations that a single dose of the AstraZeneca vaccine, which has a J.&J-like architecture, was obtained. vaccine – only shows about 33 percent effectiveness Against symptomatic disease caused by the delta variant.

“The message we wanted to convey was not that people shouldn’t buy J.&J. vaccine, but we hope it will be supplemented with vaccine in the future. or another dose of J.&J. or a support with Pfizer or Moderna,” said Nathaniel Landau, a virologist at NYU’s Grossman School of Medicine, who led the study.

Other experts said the results were as they expected because all vaccines work better when given in two doses. “I’ve always thought and often said, J.&J. The vaccine is a two-dose vaccine, said John Moore, a virologist at Weill Cornell Medicine in New York.

Dr. Moore noted several studies: monkeys and people those who have shown more events two doses of J.&J. vaccine compared to a dose. He said the new study is particularly credible because it was published by a team with no affiliation with any of the vaccine manufacturers.

But J.&J spokesperson Seema Kumar said the data from the new study “doesn’t speak to the exact nature of immune protection.” Research sponsored by the company noted that the vaccine “constitutes strong, persistent activity against the rapidly spreading Delta variant.”

The delta variant is the most contagious version of the coronavirus ever. Director of the Centers for Disease Control and Prevention, Dr. Rochelle Walensky said at a Senate session on Tuesday that it accounts for 83 percent of infections in the United States.

The variant is also essentially a last rise In infections: Although still lower than last winter, cases are increasing in all 50 states and hospitalizations are increasing in nearly all. In the two weeks ending Tuesday, the country averaged 268 deaths per day.

Delta can cause more breakthrough infections than previous forms of the virus, but more than 99 percent of hospitalizations and deaths occur among unvaccinated people. Immunization rates in the country have stalled, and just under 60 percent of adults are fully protected against the virus.

Several studies have suggested that mRNA vaccines made by Pfizer-BioNTech and Moderna will continue to be effective against coronavirus, including all variants identified so far. A recent study, for example, showed that vaccines trigger a persistent immune reaction in the body. protect from corona virus for years.

But J.&J. The vaccine was restricted because it was introduced later than mRNA vaccines. Most studies of the efficacy of coronavirus vaccines have been done in medical centers and hospitals based on samples from staff who received mRNA vaccines.

J. & J. the vaccine has been blood clot reports and one rare neurological syndromeas well as problems with infection At a manufacturing facility in Baltimore.

Small studies published It was suggested by researchers affiliated with J. & J. that the vaccine was only slightly less effective against the Delta variant than the original virus, and that the antibodies induced by the vaccine increased in strength over the course of eight months.

A virologist at Beth Israel Deaconess Medical Center in Boston, Dr. Dan Barouch, Dr. He said Landau’s team would likely have seen a similar increase in the potency of the vaccine if they had looked at the data over time. J. & J. Dr. Barouch said the potency of the vaccine against the Delta variant at Day 29 was not much different from what was reported in his own study.

“I basically don’t see any incompatibility,” he said. “The question is about kinetics, not just magnitude, because immune responses are not static over time.” The new study also didn’t take into account other components of immune defense, he added.

Landau and colleagues looked at blood samples from 17 people vaccinated with two doses of mRNA vaccine and 10 people with one dose of J.&J. Vaccine.

J. & J. The vaccine started with a lower efficacy than the mRNA vaccines and showed a greater decrease in efficacy against Delta and Lambda variants. Dr. “The lower baseline means the rest is too weak to counter Delta,” Moore said. “This is a major concern.”

Akiko Iwasaki, an immunologist at Yale University, noted that very few vaccines are given as a single dose because the second dose is needed to raise antibody levels. People vaccinated with J.&J. The vaccine “relies on this primary response to maintain high levels of antibodies that are particularly difficult against variants,” he said.

He said boosting immunity with a second dose should raise antibody levels enough to counter the variants.

Another J.&J for the second shot. could be better: A few studies suggest that one dose of AstraZeneca vaccine is one dose of Pfizer-BioNTech or modern vaccines stands up immune response more effective than two doses of AstraZeneca.

“Fully vaccinated Americans don’t need a booster vaccine at this time,” the Food and Drug Administration said, and it’s unlikely that the agency will change its recommendations based on laboratory studies. But he said the new data should prompt the FDA to reconsider its recommendations. “I hope they read our article and think about it,” Landau said.

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