A global sense of relief grew Wednesday as a second coronavirus vaccine appeared poised for approval just days after thousands of health-care workers received doses of the first one in an unprecedented mass inoculation campaign that has raised hopes for a return to normalcy.
The second vaccine, developed by the biotechnology company Moderna, was “highly effective” in a clinical trial and carried no serious safety concerns, according to a detailed review by the Food and Drug Administration published Tuesday.
The US agency is likely to authorize the two-shot regimen as soon as Friday, according to a person with knowledge of the situation who was not authorized to discuss the issue.
Such an approval would clear the way for the shipment of almost 6 million doses of the Moderna vaccine to the US in the first week — about double the amount of doses being sent out this week, Gen. Gustave Perna, who is overseeing the distribution effort, said Monday.
Those numbers represent a tiny fraction of the doses that will be required to end or even slow the pandemic in the United States.
Still, the rollout of the just-approved Pfizer-BioNTech vaccine Tuesday, and the glimmer of hope it offered at the end of a bleak year, sparked elation and tears of joy among health-care workers and ordinary people alike.
A video of staffers at Boston Medical Center jubilantly dancing on a sidewalk, shared on Twitter Monday evening by the hospital’s chief executive, circulated widely Tuesday.
In bittersweet briefings, governors hailed the arrival of vaccines in their states but warned that American life would not — could not — return to usual for many months to come.
The initially limited supplies of vaccine will not meet demand until well into 2021, and scientists do not yet know whether the Pfizer-BioNTech and Moderna vaccines, or others in development, prevent recipients from spreading the virus — or only from being sickened by it.
