NEW YORK: Pfizer Inc recently said that a booster dose of its two-shot COVID-19 vaccine spurs a more than threefold increase in antibodies against the coronavirus, as the company seeks U.S. regulatory approval for a third injection.
The drugmaker and its German partner BioNTech SE aim to complete the submission to use booster shots in people aged 16 and over by the end of this week.
The U.S. government has said it was gearing up to roll out the third shot of vaccines from both Pfizer and Moderna Inc from mid-September to Americans who had their initial course more than eight months ago if the U.S. Food and Drug Administration (FDA) and the U.S. Centers for Disease Control and Prevention (CDC) decide that boosters are needed.
The Wall Street Journal reported that that eight-month gap is likely to be narrowed to six months.
Pfizer said 306 people given a third dose of its vaccine after their second shot between five and eight months showed levels of neutralizing antibodies that were 3.3 times the levels seen after their second shot.
The study, details of which have not yet been published, also found that side effects of a third shot were similar to second-dose reactions, including mild to moderate fatigue and headache, the company said.
U.S. President Joe Biden has said, "It's the best way to protect ourselves from new variants that may arise."
However, Tedros Adhanom Ghebreyesus, Director-General, World Health Organization (WHO), said that the data on the benefits and safety of a COVID-19 vaccine booster shot is inconclusive.
The health agency called for a delay in rolling out booster shots and a goal of higher vaccination rates in countries where many had not received a first or second shot.
Earlier, U.S. regulators granted full approval to Pfizer's two-dose vaccine, which has been available up until now under emergency use authorization.
The approval spurred some local governments, such as New York City and the state of New Jersey, the U.S. military and some companies, to mandate vaccines.
A third dose of the Pfizer-BioNTech vaccine is not currently authorized for broad use in the United States.
However, under the amended emergency use authorization, a third dose was administered to individuals at least 12 years of age who were immunocompromised.
Pfizer and BioNTech said they intend to file the data with the European Medicines Agency and other regulatory authorities worldwide in the coming weeks.
(Reporting by Mrinalika Roy and Manas Mishra in Bengaluru; Deena Beasley in Los Angeles; Editing by Arun Koyyur, Mark Porter and Jonathan Oatis)
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