October 13 (News) – Food and Drug Administration scientists said Wednesday that studies suggest a booster for the Johnson & Johnson COVID-19 vaccine might provide better protection for recipients, but ultimately concluded that they are not sure when this additional vaccination should be given.
The scientists outlined their assessment of the vaccine in a 54-page document due to be presented Thursday and Friday at a meeting of the FDA’s Advisory Committee on Vaccines and Related Biological Products.
The committee will consider a motion from Johnson & Johnson to approve a booster for its single-use vaccine to extend immunity to COVID-19.
“Although the FDA has not independently confirmed any data sets, summaries of the data suggest that a second dose given approximately 2 months after the first dose may have benefit,” they wrote.
Scientists found that Johnson & Johnson subsidiary Janssen, who makes the vaccine, asked for approval for a booster six months after the initial vaccination, but also said one could be given as early as two months after vaccination.
Johnson & Johnson presented evidence to the FDA that its single dose offers less protection against the virus.
In their Wednesday document, FDA experts said the data presented made it difficult to say with certainty how effective a booster would be after six months, given that Johnson & Johnson only examined a small number of people during that period.
They also said the data doesn’t provide much information on how effective the vaccine is against the more contagious Delta variant.
“Finally, the small number of accumulated cases that have been confirmed to be caused by the Delta variant precludes any conclusion as to efficacy against that variant,” they wrote.
“[It’s not known] if there is an increased risk of these or other side effects after a booster dose. … These risks and the associated uncertainties must be taken into account when weighing up the risks and benefits. ”
In addition, the scientists said that while Johnson & Johnson’s single-dose vaccine “still offers protection from severe COVID-19 disease and death,” it is still less effective than the Moderna and Pfizer vaccines.
The scientists find that the Johnson & Johnson vaccine offers between 72% and 81% effectiveness against COVID-19 hospital stays.
On Wednesday, the agency’s scientists asked if a booster dose was needed for those who received Moderna’s vaccine. They said the two-shot regimen appears to offer adequate immunity to the virus.