WASHINGTON — Federal regulators on Tuesday authorized second booster shots of the Pfizer-BioNTech and Moderna coronavirus vaccines for anyone 50 and older, describing the move as an effort to boost waning immunity against serious illness just in case the virus will once again engulf the nation in the coming months.
The Food and Drug Administration said people in that age group could get the extra shot at least four months after their first booster. The agency also approved a second booster for people ages 12 and older with certain immune deficiencies.
The decision means tens of millions of Americans are now eligible for what would be their fourth chance. And while the public is tired of repeated doses, the move is most likely an interim one: Federal health officials say it’s entirely possible Americans of all ages will need another shot in the fall to prepare for a winter surge. The hope is that by then scientists will have reconfigured existing vaccines to work better and last longer against the variants that have emerged since November.
Federal health officials initially considered limiting second boosters to individuals at least 60 or 65 years old. But at a press conference, Dr. Peter Marks, who oversees the FDA’s vaccine division, said a lower age limit made more sense because so many Americans over 50 have chronic medical conditions that put them at risk.
While a single booster dose continues to protect most Americans from hospitalization and death from Covid-19, he said, those who are 50 or older and received their first booster more than four months ago should seriously consider taking another one. .
The Centers for Disease Control and Prevention were a little more cautious. In the fall, when the first round of boosters was approved, the agency cited a clear benefit of an additional injection.
By contrast, on Tuesday, the CDC updated its vaccine guidelines to note that second boosters are now allowed. dr. Rochelle P. Walensky, the agency’s director, said the option of a different dose was “particularly important for people over 65 and over 50 with underlying medical conditions that increase their risk of serious illness from Covid-19, as they reduce the risk of illness.” likely to benefit from receiving an additional booster dose at this point.” About a third of 50- to 65-year-olds have serious medical conditions, officials said.
The FDA made the decision with very limited data, mostly from Israel. Experts said there was quite robust data showing that there is a need for stronger protection now that variants have reduced the potency of the vaccines. There is significantly less data on whether a second booster will provide protection, and for how long. Regulators said another dose raised no new safety concerns.
The idea that just six months after federal regulators approve the first round of boosters, a new booster is already needed could increase public fatigue with Covid vaccines. The evidence now suggests that the government’s decision last fall to approve a first booster — the subject of much scientific debate at the time — saved lives over the winter. While the Omicron variant surged, those who received a boost were 21 times less likely to die from Covid and seven times less likely to be hospitalized than those who were not vaccinated, according to the CDC.
But right now, “each additional dose provides marginal value,” said Dr. Eric Rubin, an infectious disease expert at Harvard TH Chan School of Public Health. At an event hosted by Columbia University this week, Dr. Kate O’Brien, the director of the World Health Organization’s vaccine division, said: “We are in a relatively weak position on policy around exactly what the data is that makes compelling decisions about fourth doses.”
The strongest data to support a second booster came from a recently released Israeli study that has not yet been peer-reviewed. Over a 40-day period this year, the researchers studied Covid death rates among more than half a million adults ages 60 to 100 who had received at least one booster.
Of the 234,868 who had only one booster, 232 people died from Covid. Of the 328,597 people who received a second booster, 92 died from Covid. The death rate “was significantly lower among those who received an additional booster,” the researchers said.
Federal officials also studied statistical models that suggested that if the virus were to increase again in the late spring or summer, a second booster could save thousands of lives and prevent tens of thousands of hospitalizations.
The CDC expelled Johnson & Johnson recipients for special treatment. The agency has already recommended Moderna and Pfizer vaccines over Johnson & Johnson’s vaccines for safety reasons.
On Tuesday, it said adults who received a starting dose plus a booster of the Johnson & Johnson vaccine at least four months ago — a group that could include more than 1.4 million people — were eligible for a second booster containing one of the mRNA vaccines. The agency cited new data showing that Johnson & Johnson’s vaccine was less effective than the other two.
Both Pfizer and Moderna have argued for a second booster. Pfizer and BioNTech said data collected during the Omicron wave showed that the potency of their first booster diminishes within three to six months against both symptomatic infection and severe illness. Data from Israel suggests a second booster restores protection, but researchers haven’t followed the recipients of those boosters for long.
dr. Paul Burton, Moderna’s chief medical officer, told DailyExpertNews Monday that the virus’s mutations had weakened the vaccines’ shields. “The only way we can get to a period of stability and eventually an endemic disease is to keep people protected, keep their antibody levels up, and I’m afraid that means they need to be stimulated regularly,” he said.
Both Pfizer and Moderna have a clear financial incentive to promote more injections: They expect tens of billions of dollars in sales of Covid vaccines this year alone.
Neither the FDA nor the CDC convened an outside committee of experts to debate the new policy, sparking criticism. dr. Rubin, an FDA panelist, called that decision reasonable but said it was critical for the agency to make public all the data it relied on for others to investigate. The agency’s decision paper is expected to be posted online shortly.
Like other experts, Dr. Rubin that what is really needed now is a vaccine that works better than the existing ones against the new variants. Many studies are now underway to find it, but the first results are not expected until later this spring.
“It’s not really clear yet what the optimal booster should be,” said Dr. Marks.
The FDA panel will meet on April 6 to discuss what the country’s booster strategy should be. Federal health officials have suggested injections may be needed in the fall, much like the flu. “At some point,” said Dr. Marks, “we will have to realize that this is a virus that will be with us and that we have to learn to deal with it regularly.”
Another major decision looms, possibly next month, when the FDA can decide whether to approve a vaccine for the nation’s youngest children — the only group still ineligible for shots. Moderna plans to submit data in the coming weeks from what it has described as a successful clinical trial of a two-dose regimen for children under 6. Pfizer and BioNTech have said they expect results from their three-dose regimen next month. dose trial for children under 5 years of age. †
dr. Marks said Tuesday that the FDA would seek input from its advisory committee before making decisions about admissions for the youngest children.
For many of the roughly 3 percent of Americans with immune deficiencies, Tuesday’s decision authorizes what would essentially be a fifth dose. Those 12 and older can get Pfizer’s shot, while those adults can choose between Pfizer’s and Moderna’s.
How much public demand there is for another booster is unclear. With the pandemic in lull, the nation’s enthusiasm for gunfire has waned. The number of new reported infections has fallen since the third week of January, when the Omicron wave peaked.
According to CDC estimates on Tuesday, an even more contagious subvariant of Omicron, known as BA.2, is now dominant among new US cases. The subvariant has led to a wave of new cases in Europe. But some experts think the United States is bearing the brunt of its impact, in part because the Omicron variant has infected so many Americans.
Cheryl Shell, a 71-year-old retiree in the southern Michigan town of Spring Arbor, said she couldn’t wait to find out. She got her first booster in November, she said, and she’s eager to get a second one because she’s worried about dwindling potency. “I have to go for every protection I can get,” she said.
Kate Bedingfield, the White House communications director, said the new authorization is “a good thing and it’s a straightforward thing.” She said the government had sufficient supply to offer second boosters to those who are now eligible.
But she reiterated a point the White House has made repeatedly in recent weeks: If booster shots are recommended for the general population, she said, Congress will have to provide more money to pay for them.
Noah Weiland and Adeel Hassan reporting contributed.