Pfizer Seeks US Authorization of COVID-19 Boosters for Latest Omicron Variants

Pfizer Seeks US Authorization of COVID-19 Boosters for Latest Omicron Variants
A health care worker prepares a dose of Pfizer BioNTech COVID-19 vaccine in a file image. (Ezra Acayan/Getty Images)
Mimi Nguyen Ly

Pfizer and partner BioNTech announced they have submitted a request to the U.S. Food and Drug Administration (FDA) to authorize a COVID-19 vaccine booster that has been updated to target the newest Omicron subvariants.

The request comes after the FDA in June advised COVID-19 vaccine makers to amend their shots to target the two Omicron subvariants BA.4 and BA.5, which are better than ever at dodging immunity from earlier vaccination or infection.
“Data support request for Emergency Use Authorization of a 30-µg booster dose of an Omicron BA.4/BA.5-adapted bivalent COVID-19 vaccine for individuals 12 years of age and older,” the companies said in a release on Aug. 22.

The so-called bivalent vaccine that Pfizer-BioNTech is seeking authorization for contains the mRNA encoding the spike protein of the Omicron BA.4/BA.5 variant, along with the mRNA encoding the original spike protein of the original strain of SARS-CoV-2 that first emerged in Wuhan, China, in 2019.

The updated Omicron-targeted vaccine boosters could be offered to the public within weeks if the FDA quickly grants the emergency authorization. The FDA will be relying heavily on scientific testing of prior tweaks to the vaccine—rather than a large study of the newest boosters that could take months—to decide whether to issue the emergency use authorizations. The fast-track approach is similar to how annual changes to flu vaccines are handled.

The companies stated that their EUA application comes after the FDA issued a guidance telling them to include clinical data from the companies’ Omicron BA.1-adapted vaccine, as well as pre-clinical and manufacturing data from the latest Omicron BA.4/BA.5-adapted vaccine.

A mid-to-late study of a 30-µg booster dose of Pfizer-BioNTech’s Omicron BA.1-tailored vaccine showed “a favorable safety and tolerability profile” and showed that the shot elicited “a superior immune response” against the subvariant compared with Pfizer-BioNTech’s original vaccine, the companies previously announced.

Pre-clinical data showed that a dose of the updated vaccine “generated a strong neutralizing antibody response against Omicron BA.1, BA.2 and BA.4/BA.5 variants, as well as the original wild-type strain,” the companies said on Aug. 22.

Meanwhile, a clinical study investigating the safety, tolerability, and immunogenicity of the BA.4/BA.5 vaccine in people aged 12 years and older is expected to start this month, Pfizer-BioNTech stated.

Ready to Roll Out

Albert Bourla, the chairman and CEO of Pfizer, said in a statement that the company has rapidly scaled up production and is ready to immediately start distribution of the doses if it obtains regulatory clearance.
Pfizer-BioNTech has a $3.2 billion deal with the U.S. government for 105 million COVID-19 vaccine doses for a fall vaccination campaign, which covers those tailored for the new Omicron variants.
Moderna also has a deal with the U.S. government valued at up to $1.74 billion, for 66 million doses of its bivalent COVID-19 vaccine booster targeted for the new Omicron variants. Moderna is expected to file an application for emergency authorization soon.
Combined, the two agreements would make available about 171 million bivalent vaccine booster doses if they are authorized and recommended. Both Pfizer and Moderna agreements also include options for a total of 600 million doses, which comprise 300 from each company, but that can only be exercised if Congress clears additional funding.

The previously-authorized COVID-19 vaccines from the two companies have been linked with heart inflammation, including myocarditis and pericarditis, data from around the world have suggested.

Younger populations, especially young men, have been observed to experience these conditions at much higher than expected rates, data from the Centers for Disease Control and Prevention (CDC) previously suggested. A small number of deaths from heart inflammation after COVID-19 vaccine have been reported.

The primary regimens of the vaccines, which are two doses administrated several weeks apart, have been insufficient to protect against infection, and have shown waning efficacy in protecting against hospitalization amid newly emerging variants.

Dr. Rachel Presti of Washington University in St. Louis, a researcher with the Moderna trial, said of the boosters that it’s clear “none of these vaccines are going to completely prevent infection,” but also noted that previous studies of variant booster candidates suggest “you still get a broader immune response giving a variant booster than giving the same booster” again.

Dr. Ashish Jha, the White House Covid response coordinator, said last week that new COVID-19 vaccines would become available by early to mid September. He urged people to get both the updated booster shots as well as the flu shots in preparation for the coming fall and winter in hopes of preventing the need for hospitalization.
The Omicron variant BA.5 currently is responsible for nearly all COVID-19 infections in the United States and much of the world. It’s unclear whether it will pose a threat this coming winter. So far, new hospital admissions of patients with confirmed COVID-19 in the United States have been decreasing over the past month in all age groups, according to the latest data from the CDC as of Aug. 20.

“I think it’s going to be interesting to see what happens. How vigorously will the CDC recommend this bivalent vaccine if [hospitalization] rates continue to decline? How eager [will] people be to get yet another booster?” Dr. Cody Meissner, who advises the FDA on vaccines, said in an interview with The Epoch Times. “And there’s a little bit of vaccine fatigue in the United States, as you know, and so we'll have to wait and see how that plays out.”

It’s uncertain whether another variant will emerge to replace the latest BA.5 variant. Mutant strains of COVID-19 have emerged around late fall or early winter over the past two years, Meissner noted. “It’s really not possible to predict what this virus is going to do and I think it makes sense to be prepared with these boosters,” he said.

Zachary Stieber, Reuters, and The Associated Press contributed to this report.
Editor’s note: This article has been updated with more information.