The Food and Drug Administration on Thursday said it had advised COVID-19 vaccine companies to produce an updated vaccine for this fall, an aim to give people broader and stronger immunity in an upcoming booster campaign ahead of the winter.
It’s the latest step in the FDA’s strategy to better keep up with the virus, moving quicker to address variants and working to make booster doses more effective.
The announcement comes after the FDA's advisers met earlier this week to discuss the various options for updated vaccine designs. In keeping with the advisers’ recommendations, the FDA selected a vaccine that will include two strains of COVID, the original Wuhan strain and the most recent omicron sub variants, BA.4 and BA.5, which is currently making up the majority of cases.
“The COVID-19 vaccines that the FDA has approved and authorized for emergency use have made a tremendous difference to public health and have saved countless lives in the U.S. and globally,” said Dr. Peter Marks, the FDA’s vaccine chief, in a statement Thursday.
But the virus has “evolved significantly,” Marks said, making it necessary to better match the vaccines to the variants.
“As we move into the fall and winter, it is critical that we have safe and effective vaccine boosters that can provide protection against circulating and emerging variants to prevent the most severe consequences of COVID-19,” Marks said.
The hope is that updating the vaccines to more closely match the current variants will give people stronger protection for a longer period of time, and that including multiple strains of virus in the vaccine could give broader protection against new variants that are likely to arise in the future.
Still, the next few months will carry a lot of uncertainty, as manufacturers race to produce hundreds of millions of doses and the virus likely continues to mutate.
As the chair of the FDA’s advisory committee noted on Tuesday, planning vaccines ahead of time to try to protect against unknown COVID-19 variants is “unchartered territory.”
“Unfortunately -- looking in the past doesn't help us a great deal to look in the future for this virus, which has baffled a lot of us and made predictions almost irrelevant,” said Arnold Monto, the committee chair.
But experts are hopeful that updating the vaccines to bring them closer to the latest variants will still be beneficial, even if it won’t be a perfect match by fall.
MORE: Health officials plan for updated vaccines with an eye on COVID’s unpredictabilityThe government has already purchased $3.2 billion worth of vaccines from Pfizer, which amounts to 105 million doses. The order includes doses for adults, adolescents and children.
The contract came with an option to order an additional 195 million doses, bringing the total to 300 million, which would nearly cover the U.S. population.
But for now, the White House has run into funding troubles.
After months of Congressional gridlock over a request for $22.5 billion for COVID preparedness, the White House pulled $10 billion from other COVID efforts, including testing, to buy $5 billion worth of vaccines and another $5 billion of therapeutics.
MORE: Government nearly exhausts monoclonal COVID treatment funding with new purchaseThe government is likely to also contract with Moderna, which could increase the available doses, but in the meantime the White House has so far only secured enough doses to boost the country’s most vulnerable people, White House COVID coordinator Ashish Jha said Wednesday.
There are around 118 million Americans over the age of 50, 55 million of whom are 65 and older — the highest risk group for the virus. The Pfizer order alone could cover this group, if manufacturing all goes to plan.
But there are over 258 million Americans over the age of 18, and the White House said its committed to securing doses for everyone “who may benefit.”
“As we warned Congress months ago, our fall vaccine order will not be sufficient to make a vaccination available to every adult who may benefit from these new booster shots and comes with trade-offs,” Jha said, calling on Congress to act.
“We lack funding to purchase enough vaccines to cover all Americans who may want this protection.”
Of course, it remains to be seen how many Americans that will be. Only 105 million Americans have gotten their first booster dose, about half of the people who got their initial series, which could be a sign that demand for boosters will continue to be low this fall.
Both Pfizer and Moderna plan to have doses available by October and November.
Before that happens, the companies will submit their data on these vaccines to the FDA, which will issue an authorization if it finds them to be safe and effective.
The FDA has not asked the companies to alter their designs for primary doses — the initial two shots for mRNA vaccines — calling this year a “transitional period” and saying that the primary series still gives good protection against hospitalization.
ABC News' Arielle Mitropoulos contributed to this report.