U.S. Plans COVID-19 Booster Shots at Six Months Instead of Eight

Stephanie Armour and Jared S. Hopkins of The Wall Street Journal wrote:

Federal regulators are likely to approve a third Covid-19 shot for vaccinated adults starting at least six months after the second dose rather than the eight-month gap they previously announced, a person familiar with the plans said, as the Biden administration steps up preparations for delivering boosters to the public.

Data from vaccine manufacturers and other countries under review by the Food and Drug Administration is based on boosters being given at six months, the person said. The person said approval for boosters for all three Covid-19 shots being administered in the U.S.—those manufactured by Pfizer Inc. and partner BioNTech SE, Moderna Inc. and Johnson & Johnson—is expected in mid-September.

The Biden administration and companies have said that there should be enough supply for boosters. The U.S. has purchased a combined 1 billion doses from Pfizer and Moderna.

A White House spokesman declined to comment. An FDA spokeswoman declined to comment on interactions with vaccine manufacturers.

Pfizer and BioNTech said Wednesday that they had asked U.S. health regulators to authorize boosters of their Covid-19 vaccine and submitted additional data showing a third dose improves protection against the virus. The FDA granted full approval to the vaccine on Monday. Biden administration officials have said they hope full approval will encourage more people to get vaccinated, pushing up inoculation rates that recently climbed past 60% of the eligible U.S. population.

Pfizer said it couldn’t comment on potential regulatory decisions. Moderna said Wednesday that it had completed filing for full approval of its vaccine, which uses similar mRNA technology as the Pfizer-BioNTech shot. Full approval of Moderna’s vaccine is expected in about three months, the person familiar with the matter said. Johnson & Johnson has said it plans to file for approval later this year.

Federal officials last week recommended that adults who received a two-dose regimen of mRNA vaccines such as Pfizer’s begin receiving booster shots in September. Officials said at the time that the shots would be administered about eight months after the second dose for people ages 18 and older. Boosters will be administered at the 80,000 pharmacies and other vaccination sites operating across the U.S.

The effort hinges on FDA clearance of the additional shots, and a recommendation by a vaccine advisory committee of outside experts to the Centers for Disease Control and Prevention. The CDC sets recommendations on who gets priority for the vaccines and when.

Health authorities already have authorized booster shots for people 12 years old and above whose immune systems are compromised. People 65 and older and individuals in chronic-care facilities are expected to get boosters first, along with health workers and anyone else who was vaccinated earliest, according to federal health officials.

Some public-health experts have said boosters aren’t necessary based on data that shows ongoing protection against hospitalizations and death from the initial round of shots. Vin Gupta, health adviser to the Biden administration’s postelection transition team, said he believes boosters should be reserved for people with compromised immune systems, older people and people with comorbidities such as diabetes. “I don’t think there’s any compelling data for boosters for everyone at eight months,” Dr. Gupta said.

Leana Wen, health policy professor at George Washington University, said approving boosters starting at six months after a previous dose makes sense based on available data on waning immunity. “That doesn’t mean every patient needs to get a booster at six months,” she said.

Studies indicate the Pfizer-BioNTech vaccine is still highly effective in people six months after their second dose. Yet there is some evidence its efficacy might diminish over longer periods and the shot isn’t as effective against the contagious Delta variant, prompting research into adding a third dose.

Pfizer and BioNTech said Wednesday that the third dose generated a stronger immune system against the original Covid-19 strain compared with the original two-dose course.

The submission includes data from a late-stage trial of 306 subjects between 18 and 55 years who received a third dose between 4.8 and eight months after completing the two-dose course of vaccination, Pfizer said. Neutralizing antibodies—which play a key role in the immune system—were more than three times as much when measured one month after the third dose, compared with one month after the second dose.

The administration of a third dose also appeared safe in the trial, the companies said.

The companies didn’t say whether the data included how well a booster shot worked against the contagious Delta variant. However, the companies earlier this month had submitted to regulators separate results from a small, early-stage study showing a third dose of their vaccine generated higher levels of neutralizing antibodies against the original virus and against the Beta and Delta variants than the standard two-dose regimen.

Other vaccine makers also are studying whether booster doses could help maintain protection against the virus. On Wednesday, Johnson & Johnson said that a second dose of its vaccine was found in a study to generate a strong immune response, justifying a booster shot.