Moderna on Tuesday said it submitted a request for the Food and Drug Administration (FDA) to authorize an updated version of its COVID-19 vaccine targeting the latest omicron subvariants.
The application comes ahead of a fall booster shot campaign. Assuming the FDA signs off, the company said its shots will be ready to ship in September.
The application, per instructions previously given by the FDA, is for a “bivalent” vaccine that targets the BA.4 and BA.5 subvariants of omicron currently circulating, as well as the original form of the virus.
The purpose of a “bivalent” shot is to take the protection offered by the initial vaccine and then add to it by including the BA.4 and BA.5 spike protein.
Moderna’s vaccine is intended for adults aged 18 and older. Pfizer’s vaccine will be for adults and adolescents aged 12 and older.
Pfizer submitted its request for FDA authorization on Monday.
The Biden administration has procured 175 million doses of bivalent COVID-19 vaccine for distribution and administration from both Pfizer and Moderna, enough booster doses to ensure a “robust and complete national vaccination campaign through the fall and early winter,” according to the Centers for Disease Control and Prevention’s (CDC) fall vaccine planning guide.
“There will be a sufficient but finite supply of bivalent COVID-19 vaccines, which should be directed to providers with expected demand among eligible patients,” the CDC said.
According to the administration, at least one bivalent vaccine for children ages 11 years and younger may be authorized “within a short time” following the authorization of a bivalent vaccine for people ages 12 and older.
The CDC said it anticipates the bivalent vaccines will only be authorized as a single dose in people who have completed a primary vaccination series. It won’t matter how many prior booster doses a person received, so long as they’ve had their initial series.
Like Pfizer, Moderna said it does not have clinical trial data for the vaccine. Instead, the request is based on data from a booster targeting an earlier version of omicron, as well as preclinical data from mice.
Human clinical trials are currently underway, so the results won’t be available for the FDA to consider as it makes a decision.
“We have worked closely with the FDA to ensure that Americans will have access to Moderna’s updated, bivalent booster, which, if authorized, may offer higher, broader, and more durable protection against COVID-19 compared to the currently authorized booster,” Moderna CEO Stéphane Bancel said in a statement.
It remains unclear how many people will get the new boosters, despite the potential for a surge of COVID-19 over the fall and winter, given that uptake for the first booster shot has been lagging.
The BA.4 and BA.5 subvariants account for the majority of new infections in the U.S., according to the CDC.
It’s possible those variants will be eclipsed in the fall by an even more immune-resistant strain, but the hope is that even if the vaccines target old variants they will provide broad protection against anything new.