While it was so widely expected the announcement was merely a formality, just after 5pm on Friday the FDA Advisory Panel voted unanimously (22-0) to endorse the (one-shot, no mRNA) J&J vaccine, saying the benefits outweigh the risks, and recommended the agency grant emergency authorization, moving the nation’s third vaccine one step closer to getting into Americans’ arms.
The vaccine was 66% effective in protecting any cases of moderate to severe illness. It was 85% effective against severe cases of COVID-19 and completely prevented hospitalizations and death, four weeks after inoculation.
The FDA could now give the green light to the single-dose vaccine as early as Saturday, and it probably will.
Vaccinations will then begin as soon as a Centers for Disease Control and Prevention (CDC) panel recommends the vaccine and the CDC accepts that recommendation. The CDC panel is scheduled to meet Sunday.
“We are at the precipice of having another vaccine in our toolbox,” CDC Director Rochelle Walensky said Friday. “Having an additional safe and effective vaccine will help protect more people faster.”
The Johnson & Johnson (J&J) vaccine is different from the other two already on the market and could be a potential game changer. It is administered in a single dose, and does not need to be frozen when shipped and stored. It is also not based on the highly controversial mRNA technology used by Pfizer and Moderna. Unlike those two, the JNJ vaccine is what’s called a viral vector vaccine.
To create this vaccine, the Johnson & Johnson team took a harmless adenovirus – the viral vector – and replaced a small piece of its genetic instructions with coronavirus genes for the SARS-CoV-2 spike protein.
After this modified adenovirus is injected into someone’s arm, it enters the person’s cells. The cells then read the genetic instructions needed to make the spike protein and the vaccinated cells make and present the spike protein on their own surface. The person’s immune system then notices these foreign proteins and makes antibodies against them that will protect the person if they are ever exposed to SARS-CoV-2 in the future.
The adenovirus vector vaccine is safe because the adenovirus can’t replicate in human cells or cause disease, and the SARS-CoV-2 spike protein can’t cause COVID–19 without the rest of the coronavirus.
“We need vaccines that are effective and well-tolerated. And importantly, ones that are simple to deploy,” said Gregory Poland, director of the Mayo Clinic’s vaccine research group, who spoke to the panel as part of J&J’s presentation.
The endorsement from the FDA panel of experts comes as politically motivated federal officials are again scrambling to boost the panic meter by warning about the impact of recent highly contagious variants of the coronavirus, urging people not to grow complacent despite plunging cases and hospitalizations. The rise of variants makes vaccination more important than ever, CDC officials said.
CDC epidemiologist Adam MacNeil told the FDA panel said he expects the B.1.1.7 variant, first found in the United Kingdom, has likely spread throughout the entire U.S., and could become the dominant virus in mid-to-late March. However, inadequate genetic sequencing means we may never get the true picture. Furthermore, recent computer models have predicted that not even covid variants will prevent the US from basically being covid free by June.