The coronavirus vaccine developed by Moderna triggers an immune response that protected in laboratory tests against two variants of the virus first detected in Britain and South Africa, the company said Monday.
The finding was largely encouraging but contained a clear warning sign: Even though the vaccine generated disease-fighting antibodies that worked against the South African variant, that efficacy was diminished. Moderna said there was a reduction in response, prompting the company to design a new potential vaccine that could be added to the current two-dose regimen.
As a precaution, Moderna announced that it will begin two new studies. The company will test adding a third shot of its current vaccine to boost its two-dose regimen. The biotechnology company also plans early human tests of the all-new vaccine specific to the South African variant, using it as a booster to prime the immune system to the new strain.
The Biden administration announced Wednesday that it would distribute more than 25 million masks to over 1,300...
