New York, 3 January 2022 (dpa/MIA) - The US Food and Drug Administration (FDA) has expanded its emergency use authorization of a booster dose of the Pfizer/BioNTech Covid-19 vaccine to include young people from the age of 12 and up. The booster dose is the same dosage strength (30-microgram) as the dose approved in the primary series, the companies said in a statement. The FDA previously authorized a booster dose of the Pfizer/BioNTech Covid-19 vaccine for emergency use after completion of a primary series in individuals 16 years of age and older. The vaccine is also authorized for eligible individuals 18 and older who have completed primary vaccination with a different authorized Covid-19 vaccine. In addition, the FDA has amended the existing emergency use authorization to reduce the time for administration of a booster dose from at least six months to at least five months following completion of the primary series for individuals 12 years of age and older. The FDA has expanded the current Emergency Use Authorization to include administration of a third primary series dose at least 28 days following the second dose for individuals 5 through 11 years of age who have who have been determined to have certain kinds of immunocompromise. A third primary dose of the Pfizer/BioNTech vaccine was previously authorized for administration to individuals at least 12 years of age who have been determined to have certain kinds of immunocompromise. Pfizer and BioNTech said that they fulfilled their goal to deliver 1 billion doses of their Covid-19 vaccine to low- and middle-income countries in 2021.