This change shows that the FDA is trying to be more nimble in its efforts to keep up with a changing virus. The exact formulation has yet to be tested in humans, but studies show that vaccines tailored to earlier versions of omicrons modestly increase short-term immune responses in humans compared with more shots of the original vaccine. The agency will depend in part on that data when considering new vaccines.
On Thursday, the FDA advised companies to create a two-part vaccine for a fall booster campaign. Part of the vaccine will be the initial formulation, based on the version of the virus spreading globally in early 2020. The rest will be based on the BA.4 and BA.5 omicron subvariables that currently make up half of the strains. sequenced in the United States.
Chances are that BA.4 and BA.5 will be eclipsed by new variants in the fall, but it is hoped that a new dose of the drug will help extend immunity, as they are closer to where the virus is located today. now. A scientist from Pfizer showed data to FDA advisors on Tuesday that in mice, a vaccine based on those omicron versions appeared to induce a stronger immune response.
For a year and a half, a coronavirus vaccine based on the original version of the virus has provided strong protection, especially against severe illness. But immunity waned over time, and the virus proved cunning, spawning an ever-growing Greek alphabet of new variants that were more contagious and harder to slip by defenses. human immunity.
“As we move into the fall and winter, it is important that we have safe and effective vaccine boosters that can protect against circulating and emerging variants to prevent those the most serious consequences of covid-19,” FDA statement speak.
Experts were distressed that such a consequential decision had to be made based on very limited data. It is possible that the change could provide a detectable increase in protecting people against severe illness and possibly infection, but it is uncertain.
John Moore, professor of microbiology and immunology at Weill Cornell Medicine. “We don’t know and have no way of knowing really.”
The modified vaccine will be used as a booster dose. People who are still getting their first shot will continue to receive the original version of the vaccine.
People unvaccinated or unvaccinated An FDA official who asked not to be named said vaccination should not be given up in the hope of a new shot, especially given the high level of transmission. People are still likely to be eligible for a booster shot in the fall, and all vaccines are best at protecting against severe illness and hospitalization.
The federal government announced Thursday that it has agreed to purchase 105 million doses Pfizer’s Reboot Vaccine for $3.2 billion. At $30.50 a dose, that’s a premium over the initial contracts the government made for the original vaccine in 2020, when it was $19.50 per dose. dose.
Pfizer has said that its vaccine prices will likely increase after the pandemic, and this may not be the ceiling.
“We expect this to be just a second upside move between pandemic valuations and future trade valuations,” SVB Securities Research analysts wrote in an announcement analyst note.
Moderna President Stephen Hoge told the FDA advisory committee that his company will take until late October or early November to create a vaccine based on the BA.4 and BA.5 versions of omicron. It is unclear on Thursday what the company’s schedule will be to deliver the refurbished doses to the United States.