The U.S. drug regulator on Friday granted an emergency use authorization for Moderna Inc.'s coronavirus vaccine, setting the stage for the rollout of the second vaccine to fight the pandemic in the United States.

The vaccine, which requires two doses administered one month apart, will be distributed for use in individuals 18 years of age or older. It was confirmed through a clinical trial to be 94.1 percent effective in preventing COVID-19, the illness caused by the virus, according to the Food and Drug Administration.

A scientist works in the lab at Moderna in Cambridge, MA on Feb. 28, 2020. (The Boston Globe/Getty/Kyodo)

The U.S. biotechnology company filed its application with the FDA on Nov. 30, 10 days after the one filed by U.S. pharmaceutical giant Pfizer Inc. and its German partner BioNTech SE for their vaccine.

The United States started offering shots of the Pfizer vaccine on Monday and inoculation using the Moderna vaccine is reportedly to start in the coming days.

Common side effects of both vaccines include pain at the injection site, tiredness, headaches and muscle pain.

But concerns linger over the safety of COVID-19 vaccines, which have been developed in a remarkably short period of time -- less than one year.

Like the Pfizer vaccine, U.S. regulators said the Moderna vaccine should not be given to individuals with a known history of severe allergic reaction to any component of the vaccine "out of caution."

In an effort to pitch vaccine safety, U.S. Vice President Mike Pence and others publicly received a shot of the Pfizer vaccine earlier Friday. President-elect Joe Biden is also expected to be vaccinated in public next week, according to U.S. media.

The United States, which has a population of some 330 million, is expected to have enough doses to vaccinate 20 million people by the end of the year, according to the government.

In the United States, more than 17.4 million people have been infected and 313,000 have died in the pandemic, with both figures higher than for any other country in the world, according to a Johns Hopkins University tally.

Japan, meanwhile, has an agreement with Pfizer to receive a supply of 120 million vaccine doses, enough for 60 million people, or roughly half its population, in the first half of next year.

The country also has an agreement with Moderna for enough vaccine doses to cover 25 million people.


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