Moderna’s chief executive on Wednesday discussed the biotech’s progress in developing a booster shot against COVID-19 variants, saying the company hopes to have authorization from the Food and Drug Administration on one of three booster strategies by the end of the summer or early fall.
Speaking from the company’s Norwood facility during a press briefing with Governor Charlie Baker, Stéphane Bancel said Moderna is working on three different options for a single-dose booster shot against variants of concern: the current vaccine, a new variant-specific vaccine, and a 50/50 mix of the two.
Moderna last week shared early study results that showed its first two options — the current vaccine at half the dosage and a shot of its reworked vaccine — both appeared to raise antibody levels against variants that first emerged in South Africa and Brazil. Bancel said the company is expecting to receive data on the third booster strategy in the coming weeks.
“And then we’ll work with the FDA to get the safe and effective variant-specific booster to the American people as fast as we can,” he added.
The data showed that Moderna’s current vaccine “looks good” in protecting against variants, Bancel said, but the reworked vaccine tailored to fight off newer strains of the virus “looks stronger” against the B.1.351 variant first identified in South Africa.
Bancel said it’s “not impossible” that a booster could be ready for the fall for people who were vaccinated against COVID-19 in December 2020 or early January, especially for high-risk groups.
“When we have that data [on the third booster strategy] in the clinic, we will pick which one we’ll take for authorization,” Bancel said. “We’re hoping that toward the end of the summer or early fall, we should be able, if the data is good, to have authorization for a boost to be used in the fall to protect all of us so that we can have a good fall and a next good winter.”
Bancel also said the company is working with federal officials to test “the mixing of vaccines,” ensuring that regardless of which vaccine a person initially received, it will be safe for them to get Moderna’s booster shot.
Bancel also provided an update on the emergency authorization of Moderna’s vaccine in adolescents, noting that last week the company shared initial data on its COVID-19 vaccine trial in children 12 to 17 years old.
“We shared last Wednesday news that the Moderna vaccine in the 12 to 17 years of age has 96 percent efficacy,” Bancel said. “The safety profile is like what we saw for the adults, and we’re working with the FDA to get the vaccine authorized as soon as we can.”
On Monday, the FDA cleared Pfizer’s vaccine for adolescents 12 to 15 years old, and advisers to the Centers for Disease Control and Prevention met Wednesday to issue recommendations on how to vaccinate those in that age group.
Baker said Wednesday that the state has been making plans to vaccinate 12- to 15-year-olds, a group he estimates to number around 400,000.
Moderna is continuing to study its vaccine for children 6 months to 11 years old, Bancel said, and that data is expected to take a few more months.
“We have to go very slow down in age to ensure the safety of the children,” Bancel said. “And we’re also starting at the lower dose, because given their lower weight, we might need to lower the dose for children. But for the teens, it will be the exact same dose, which will help the distribution of a vaccine.”
Jonathan Saltzman and Martin Finucane of the Globe staff contributed to this report.