A key advisory committee to the Food and Drug Administration voted unanimously on Thursday to recommend a booster shot of the Moderna coronavirus vaccine for many of the vaccine’s recipients, at least six months after a second dose.
The panel endorsed a half-dose as a third injection for people 65 and older as well as younger adults at high risk because of their medical conditions or jobs, the same groups of people who became eligible for a Pfizer-BioNTech booster last month. While regulators are not obligated to follow the panel’s recommendations, they typically do.
Although committee members decried the lack of more robust data justifying a booster shot, several emphasized that F.D.A. had already set a precedent by authorizing additional shots on an emergency basis for many recipients of the Pfizer-BioNTech vaccine.
“From a pragmatic point of view,” said Dr. Stanley Perlman of the University of Iowa, “because we’ve already approved it for Pfizer, I don’t see how we can possibly not approve it for Moderna.”
Although the vote was unanimous, a number of panel members expressed serious doubts on a follow-up question: whether to expand groups of people eligible for booster shots to include younger adults who are not at high risk because of their medical conditions, jobs or other factors. They cited limited data and concerns about the underlying rationale for including younger age groups.
Some expressed angst over trying to balance the demands of a public emergency with the lack of robust data that more protection was needed.
Another committee member, Dr. Patrick Moore, an expert at the University of Pittsburgh, said that he voted to recommend a booster shot of Moderna based upon a “gut feeling, rather than based on really, truly serious data.” He added that the data suggested that the evidence was “going in a direction” supportive of booster shots.
“I just worry that we haven’t clearly defined what the goal” is, said Dr. Paul Offit, an infectious disease expert with the Children’s Hospital of Philadelphia. He called a decline in neutralizing antibodies and an erosion of protection against mild or asymptomatic infection “inevitable,” adding “that is a high bar to which we hold no other vaccine.
“The F.D.A.’s highest-ranking vaccine regulator, Dr. Peter Marks, said the agency had “heard pretty loud and clearly that there was not a lot of appetite for moving down the age range very significantly, if at all.” He said that regulators would take that perspective into consideration.
The panel voted after hearing from Moderna officials, agency scientists and a top public health official from Israel, which began offering boosters to Pfizer recipients two and a half months ago.
Dr. Eric Rubin, an adjunct professor of immunology and infectious diseases at the Harvard T. H. Chan School of Public Health, questioned whether Moderna has enough data showing whether a booster shot will create adverse side effects.
Like Pfizer, “Moderna is presenting the results of a relatively small trial,” he said. But “Pfizer had all those real-world data from Israel” on its booster campaign, showing results from “millions of people who received the vaccine,” he said.
Johnson & Johnson has asked the Food and Drug Administration to issue emergency use authorization for a booster for recipients of their vaccines, and the panel will vote Friday on the company’s request. They will also hear then about the initial results of an ongoing federal study that found Johnson & Johnson recipients may benefit more from a booster of Moderna’s or Pfizer’s vaccine.
In making its case for a booster last month, Pfizer-BioNTech argued that its vaccine, while highly protective in the early months, lost some potency against severe Covid and hospitalization over time. About the same time, a study by the Centers for Disease Control and Prevention found the efficacy of the Pfizer-BioNTech vaccine against hospitalization fell from 91 percent to 77 percent after a four-month period following the second shot.
What to Know About Covid-19 Booster Shots
The F.D.A. authorized booster shots for a select group of people who received their second doses of the Pfizer-BioNTech vaccine at least six months ago. That group includes: Pfizer recipients who are 65 or older or who live in long-term care facilities; adults who are at high risk of severe Covid-19 because of an underlying medical condition; health care workers and others whose jobs put them at risk. People with weakened immune systems are eligible for a third dose of either Pfizer or Moderna four weeks after the second shot.
The C.D.C. has said the conditions that qualify a person for a booster shot include: hypertension and heart disease; diabetes or obesity; cancer or blood disorders; weakened immune system; chronic lung, kidney or liver disease; dementia and certain disabilities. Pregnant women and current and former smokers are also eligible.
The F.D.A. authorized boosters for workers whose jobs put them at high risk of exposure to potentially infectious people. The C.D.C. says that group includes: emergency medical workers; education workers; food and agriculture workers; manufacturing workers; corrections workers; U.S. Postal Service workers; public transit workers; grocery store workers.
It is not recommended. For now, Pfizer vaccine recipients are advised to get a Pfizer booster shot, and Moderna and Johnson & Johnson recipients should wait until booster doses from those manufacturers are approved.
Yes. The C.D.C. says the Covid vaccine may be administered without regard to the timing of other vaccines, and many pharmacy sites are allowing people to schedule a flu shot at the same time as a booster dose.
But Moderna’s potency against hospitalization has held up better over time than Pfizer’s, the study found.On Thursday, Moderna did not argue that its vaccine requires a booster to prevent severe disease or hospitalization. Instead, it concentrated its arguments on preventing infection and mild to moderate disease.
Moderna said the mean antibody level of participants in its study was 1.8 times higher after the booster than it was after the second shot, meeting the F.D.A.’s criteria. But tests showed the booster narrowly failed to meet another requirement. It raised neutralizing antibodies at least fourfold in 87.9 percent of people compared to after the second dose, while the agency required that level of boost for 88.4 percent of participants.
Given that Moderna’s vaccine appears to still strongly protect against severe disease, at least some committee members may balk at recommending a booster. “Maybe it won’t be a slam dunk,” said Dr. Peter J. Hotez, a vaccine expert at the Baylor College of Medicine, in an interview Wednesday. “Maybe we should wait a little bit longer on Moderna, let it drop off more first before we boost.”
One of the first presentations Thursday came from Israeli health officials, who said their booster campaign for Pfizer-BioNTech vaccine recipients significantly lowered rates of infection and severe disease.
The Biden administration has been closely watching Israel’s experience because the country has a nationalized health care system that allows it to closely track recipients.
In a brief presentation using data from a federal safety monitoring program, Dr. Hui-Lee Wong, an F.D.A. official, cited an elevated risk in men between ages 18 and 25 who were fully vaccinated with either Moderna’s or Pfizer’s vaccines of myocarditis or inflammation of the heart muscle, and pericarditis or inflammation of the lining around the heart.
Occurrences of those side effects increased after the second dose, she said. Preliminary reports of the side effects did not suggest one vaccine was riskier than the other, but Dr. Wong cautioned that a conclusion was uncertain because of the small number of cases.
The findings aligned with what federal regulators and scientists already know. The F.D.A. in June attached warnings describing the risk to the labels for both vaccines.