An influential advisory committee to the Food and Drug Administration on Friday firmly opposed a plan to give boosters of Pfizer and BioNTech’s Covid-19 vaccine to the general public, saying it needed more data.
However, the panel could still clear the shots for older populations. After their first vote, the scientists continued to discuss the need for a third dose of the vaccines for older populations and left open the possibility of further votes.
The non-binding decision by the FDA’s Advisory Committee on Vaccines and Related Biological Products comes after the Biden government announced that it would offer booster injections to the public as early as next week pending approval from US health regulators. Although the agency has not always followed the advice of its committee, it often does. A final FDA decision could be made in a matter of hours. The Centers for Disease Control and Prevention has scheduled a two-day meeting next week to discuss plans to distribute the third syringes in the United States
The committee’s vote was expected to be controversial as some scientists, including two senior FDA officials who were involved in Friday’s meeting, said they weren’t entirely convinced that any American who did the Pfizer vaccine now needed additional doses.
In a paper released a few days prior to the advisory committee meeting, a leading group of scientists said the available data showed that vaccine protection against serious illnesses persists even as efficacy against mild illness wears off over time. The authors, including two senior FDA officials and several World Health Organization scientists, argued in the medical journal The Lancet on Monday that widespread use of booster syringes to the general public is currently inappropriate.
Outlining plans last month to start distributing boosters as early as next week, administrative officials cited three CDC studies showing that vaccine protection against Covid had waned over several months. Senior health officials said at the time they feared protection from serious illness, hospitalizations and deaths could “wear off” in the coming months, especially for those at higher risk or vaccinated during the earlier stages of vaccination.
Before the vote, some committee members said they were concerned that there was not enough data to make a recommendation, while others argued that the third vaccination should be limited to specific groups such as serious illness. Some members raised concerns about the risk of myocarditis in younger people and said more research was needed.
Dr. Hayley Gans, a voting member, said she was “concerned” that the FDA asked the committee to review the entirety of the evidence presented Friday because some data, including on safety, were still inadequate.
Another member, Dr. Paul Offit said he would support boosters for people over 60 but struggled to support a third vaccination for younger groups due to a higher risk of myocarditis.
Ahead of Friday’s vote, the committee listened to several presentations on data supporting the widespread use of booster vaccinations, including by health officials in Israel, where officials in front of many other countries began vaccinating the country’s population and giving their citizens third vaccinations to offer at the end of July.
Phil Krause, an FDA vaccine regulator and co-author of The Lancet, criticized the results presented Friday, saying that much of the data had not been federally vetted or peer-reviewed. He said the models used are complex and scientists need to make sure they are “getting the right results”.
“That’s part of the difficulty of looking at this type of data without a way for the FDA to review it,” he said.
In documents released by the FDA on Wednesday, Pfizer said an observational study in Israel showed that a third dose of the Covid vaccine restored infection protection to 95% six months after a second vaccination. The data was collected from July 1 to August 30, when the rapidly expanding delta variant emerged across the country.
In a presentation on Friday, Dr. Sharon Elroy-Price of the Israeli Ministry of Health said that if officials there had not started distributing boosters in late July, the country would likely have exceeded its hospital capacity. Health officials began to see a trend that people in their 40s and 50s who were fully vaccinated became seriously ill with Covid.
“We didn’t want to wait to see these results and we knew we had to vaccinate a larger section of the population to get the numbers down quickly,” she told the committee. Israeli health officials expected an average of 2,000 serious cases by the end of August, she said. “We have been able to dampen this effect and our severe cases are around 700 or less and have remained stable even though we still have days with 10,000 confirmed cases.”
She also said the booster was well tolerated by many people, citing data showing that out of approximately 2.9 million people who received the additional doses, there was only one case of myocarditis, a rare inflammation of the heart that occurred with mRNA vaccines.
Pfizer’s booster side effects are also similar to those seen after receiving the second dose of vaccine, said Dr. Joohee Lee, an official with the FDA’s Vaccine Research and Verification Bureau, during the meeting.
Of the 289 booster recipients, ages 18 to 55 years old, observed in Pfizer’s Phase 3 study, 63.8% developed fatigue, 48.4% headache, and 39.1% muscle pain. The FDA examined side effects in 2,682 recipients of Pfizer’s second dose of Covid aged 16 to 55 years and reported fatigue in 61.5% of patients, headache in 54%, and muscle pain in 39.3%. One adverse event – swelling of the lymph nodes – occurred in 5.2% of booster recipients, but only 0.4% of those who received their first two doses.
“The majority were mild to moderate and they subsided,” Lee said of the lymphadenopathy cases. “Though one is reported to be underway right now.”
This is a developing story. Please check again for updates.