U.S. drug regulators on Wednesday said a second shot of Johnson & Johnson’s COVID-19 vaccine could bolster people’s protection against the disease, but that they did not have enough time to independently analyze the data the company submitted.
The primary series for the Moderna and Pfizer jabs, which each utilize messenger RNA technology, are two shots each. Johnson & Johnson (J&J) was trumpeted early this year for being a single-shot vaccine, but scientists with the company say waning effectiveness against infections means a booster is now needed.
“Based on recent data, administration of a booster dose resulted in increased protection against symptomatic COVID-19, increased strength, and breadth of immune responses against variants and increase [sic] protection against severe/critical COVID-19,” they added.
The main trial exploring the safety and efficacy of a booster involved 7,484 participants getting a second shot and 7,008 people who received two doses of placebo. The booster bolstered protection against both symptomatic COVID-19 and severe cases of the disease, the company said.
However, the scientists said they did not have enough time to independently review much of the data, outside statistics regarding immunogenicity in a tiny set of 17 participants who got a booster 6 months after the first shot.
Except for that data, datasets “were not submitted in sufficient time for FDA to conduct an independent review to verify the Sponsor’s analyses,” the FDA said.
“Although not independently confirmed by FDA from datasets, summaries of the data suggest there may be a benefit in a second dose administered approximately 2 months after the primary dose,” they said.
The FDA did not respond to a request for comment.
The expected benefit will depend on factors including the effectiveness of the initial J&J shot over time and against circulating variants and the risks of a second shot in certain groups, the document said.
The FDA’s vaccine advisory panel is set to meet on Thursday and Friday to weigh whether to recommend boosters for any Americans, several weeks after advising the agency to authorize boosters for everybody 65 and older and several other populations.
On Thursday, the panel will hear from Moderna and FDA scientists. The following day, J&J scientists will present, as will experts from the FDA.
Some scientists support boosters while others do not. Many say boosters should be reserved for groups like the immunocompromised who have seen a dip in protection against hospitalization and death.
Overall, data from various studies show the COVID-19 vaccines holding up well against severe disease.
Dr. David Boulware is a professor of medicine at the University of Minnesota’s Department of Medicine. He told The Epoch Times in an email that the immune response to the J&J booster “looks appropriate,” though he noted the small study only included 17 people.
“At 6 months after their initial vaccination, only 59 percent had a detectable antibody. 28 days after the booster, all had a detectable antibody, and the average increase was 4.5-fold increase. A 4-fold increase is considered a ‘good’ response,” he said. With J&J’s shot, “that is not automatically taken for granted, as the body could have antibodies against the vector itself, blocking any increase antibody response to coronavirus,” he added.
Boulware said the safety data appeared fine though series adverse events such as blood clotting are unlikely to be detected in small trials.
Also on Friday, the National Institutes of Health will present data from a study on mixing and matching boosters or using different vaccines for a booster than a person received for their initial regimen.
Only two severe adverse events were reported, according to the study, and they were allegedly unrelated to the vaccinations. The number of adverse events of any severity was between 12 and 16 percent, depending on the type of vaccine one received.
All groups saw a boost in protection but the best boosts were among those who got a Moderna vaccine and a Moderna booster, followed by those who received a Pfizer series before getting a Moderna booster and a Moderna series then a Pfizer booster.
Participants who initially received a J&J shot got a strong boost from a Pfizer or Moderna jab.
“These data suggest that boosting with the original mRNA-1273 vaccine could maintain continued protection against variants of concern and comports with previous reports,” researchers wrote.