The coronavirus vaccine made by Johnson & Johnson is far less effective against delta and lambda variants than the original virus, according to a new study Posted online on Tuesday.
The findings provide evidence that 13 million people vaccinated with J.&J. The authors said the vaccine may require receiving a second dose — ideally one of the mRNA vaccines made by Pfizer-BioNtech or Moderna.
But the findings line up with those of smaller studies published by Johnson & Johnson earlier this month suggesting that a single dose of the vaccine is effective against the variant even eight months after vaccination.
The new study has not yet been reviewed or published in any scientific journal, and relies on laboratory experiments. But this is in line with observations that a single dose of the AstraZeneca vaccine – which has a similar architecture to J&J. Vaccines — Shows only about 33 percent efficacy Against symptomatic disease caused by delta type.
“The message we wanted to give was not that people should not get J&K vaccine, but we hope that in future, it will be promoted Either that or another dose of J.&J. Or boost 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 are what they expected, as all vaccines work better when given in two doses. “I have always thought, and often said, that the J.&J. vaccine is a two-dose vaccine,” said John Moore, a virologist at Weill Cornell Medicine in New York.
Dr. Moore pointed to several studies: monkeys and people what is shown more efficacy With two doses of J.&J. vaccine, as compared to a single dose. He said the new study was particularly credible because it was published by a team that had no affiliation with any vaccine manufacturer.
But the data from the new study “do not talk about the full nature of immune protection,” said Jammu and Kashmir spokesperson Seema Kumar. Company-sponsored studies indicate that the vaccine “produces strong, consistent activity against the rapidly spreading delta variant,” she said.
The delta variant is by far the most contagious version of the coronavirus. It is responsible for 83 percent of infections in the United States, said director of the Centers for Disease Control and Prevention, Dr. Rochelle Valensky said in a Senate hearing on Tuesday.
This may also be primarily to blame for the recent increase in infections: although they are still lower than last winter, cases are rising in all 50 states, and hospitalizations are increasing in nearly all of them. In the two weeks ending Tuesday, the country reported an average of 268 deaths per day.
Delta may cause more successful infection than earlier forms of the virus, but more than 99 percent of hospitalizations and deaths are occurring in unvaccinated people. Vaccination rates in the country have stalled, with only less than 60 percent of adults fully protected from the virus.
Several studies have suggested that mRNA vaccines made by Pfizer-BioNtech and Moderna will maintain their efficacy against coronaviruses, including all variants identified so far. For example, a recent study showed that vaccines trigger a persistent immune response in the body that can protect against the coronavirus for years.
July 20, 2021 at 4:10 pm ET
But the evidence on J.&J. The vaccine has been limited, as it was rolled out later than mRNA vaccines. Most studies of the effectiveness of coronavirus vaccines were conducted in medical centers and hospitals that relied on samples from staff members who received mRNA vaccines.
J&J. The vaccine has also been linked to reports of blood clots and a rare neurological syndrome, as well as contamination problems at a manufacturing plant in Baltimore.
small studies published by researchers affiliated with J&J. suggested 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 eight months.
A virologist at Beth Israel Deaconess Medical Center in Boston, Dr. Dan Barouch said that Dr. Landau’s team probably would have seen a similar increase in the vaccine’s potency if they had looked at the data over time. Data on J.&J. The vaccine strengths against the delta variant on Day 29 are not much different from those reported in their own study, Dr. Barouch said.
“Fundamentally I don’t see any difference,” he said. “The question is of kinetics, not just magnitude, because immune responses are not stable over time.” He said the new study also did not consider other components of immune defense.
Dr. Landau and his colleagues looked at blood samples taken from 17 people who had been immunized with two doses of an mRNA vaccine and 10 people with a single dose of J.&J. Vaccination.
J&J. The vaccine started with a lower efficacy than mRNA vaccines and showed a major drop in efficacy against delta and lambda variants. “The lower baseline means that what is left of Delta is too weak to counteract,” Dr Moore said. “It’s a big concern.”
Very few vaccines are given as a single dose, because a second dose is needed to increase antibody levels, said Akiko Iwasaki, an immunologist at Yale University. People who were vaccinated with J.&J. Vaccines “rely on that primary response to maintain high levels of antibodies, which is difficult, especially against variants,” she said.
Boosting immunity with a second dose should raise antibody levels high enough to counteract the variant, he said.
Turning to mRNA vaccine for a second shot instead of another J.&J. The shot may be better: Several studies have shown that combining a dose of the AstraZeneca vaccine with a dose of Pfizer-BioEntech or moderna TK kick up immune response More effective than two doses of AstraZeneca.
The Food and Drug Administration has said that “Americans who have been fully vaccinated do not need a booster shot at this time,” and the agency is unlikely to change its recommendations based on laboratory studies. But should the new data prompt the FDA to reconsider its recommendations, Dr. Landau said: “I hope they read our paper and think about it.”