NEW YORK, July 8 (Reuters) – Pfizer Inc (PFE.N) is considering asking U.S. regulators to allow a booster dose of its COVID-19 vaccine within the next month, the manufacturer’s lead scientist said Thursday on Thursday. drugs, based on evidence of an increased risk of re-infection six months after inoculation and spread of the highly contagious Delta variant.
The US Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC), however, said in a joint statement that Americans who have been fully vaccinated do not need a COVID-19 booster. for the time being.
Some scientists have also questioned the need for booster doses.
Pfizer Scientific Director Mikael Dolsten said the recently reported drop in vaccine effectiveness in Israel was mainly due to infections in people who had been vaccinated in January or February. The country’s health ministry said the vaccine’s effectiveness in preventing infections and symptomatic illnesses fell to 64% in June.
âThe Pfizer vaccine is very active against the Delta variant,â Dolsten said in an interview. But after six months, he said, “there is probably a risk of re-infection because the antibodies, as expected, go down.”
Pfizer did not release the full Israeli data set on Thursday, but said it would be soon.
“It’s a small set of data, but I think the trend is right: in six months, given that Delta is the most contagious variant we’ve seen, it can cause mild infections and illnesses,” he said. Dolsten said.
The FDA and CDC, in their joint statement, said, âWe are ready to receive booster doses if and when science shows they are needed. “
Pfizer’s own data in the United States showed an erosion of the vaccine’s effectiveness in the mid-1980s after six months, Dolsten said, against the variants circulating there in the spring.
He pointed out that data from Israel and Britain suggests that even with decreasing antibody levels, the vaccine remains around 95% effective against serious illness.
The vaccine, developed with German partner BioNTech SE, showed 95% effectiveness in preventing symptomatic COVID-19 in a clinical trial conducted by the companies last year.
Dolsten said early data from the company’s own studies shows that a third booster dose generates antibody levels five to ten times higher than after the second dose, suggesting that a third dose will offer promising protection. .
He said several countries in Europe and elsewhere have already approached Pfizer to discuss booster doses, and some may start giving them before a possible US authorization.
Dolsten said he thinks booster shots are especially important in the older age groups.
Dr Eric Topol, professor of molecular medicine and director of the Scripps Research Translational Institute in La Jolla, Calif., Said basing the decision on decreased antibody protection ignores the role of other important parts of the immune response, including memory B cells, which can make antibodies on demand when challenged by the virus.
âYou need better studies to be able to say that. It’s not just about neutralizing antibodies,â Topol said.
Pfizer has previously said people would likely need a booster dose, although some scientists have questioned when or if boosters would be needed.
Pfizer plans to launch a placebo-controlled booster efficacy trial with 10,000 participants in the near future. The study will run throughout the fall, Dolsten said, which means it won’t be complete until the company files with the Food and Drug Administration.
Dr William Schaffner, a vaccine expert at Vanderbilt University Medical Center, said that even if Pfizer was successful in getting its recall cleared by the FDA, it would only be the first step. The recall should still be reviewed and recommended by CDC advisers.
“It is by no means automatic,” he said. Schaffner has realistically stated that most of the public health bandwidth in the United States is still aimed at encouraging Americans to get their first and second doses of the vaccine.
Because boosters would lead to growing demand for vaccines when much of the world is still unvaccinated, Dolsten said Pfizer is looking for ways to increase production.
It is already targeting the production of 3 billion doses this year and 4 billion doses next year. Dolsten declined to give an exact prediction of how many extra doses the company might add, but said, “We can increase billion after billion in 22.”
Dolsten also said that Pfizer and BioNTech are designing a new version of the vaccine targeting the Delta variant, but said the companies don’t believe the current version will need to be replaced in order to combat the variant.
Pfizer expects the COVID-19 vaccine to be a major contributor to revenue for years to come and forecasts $ 26 billion in sales from the vaccine in 2021. Global spending on COVID-19 vaccines and recalls could total $ 157 billion through 2025, according to data from US health care company IQVIA Holdings.
Reporting by Michael Erman; Additional reporting by Julie Steenhuysen in Chicago and Kanishka Singh in Bengaluru; Editing by Dan Grebler and Leslie Adler
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