Half doses of vaccine?

The U.S. coronavirus vaccine team is in discussions with Moderna and the FDA about whether to allow people to receive two doses of that vaccine at half the strength, Moncef Slaoui, the chief science adviser for Operation Warp Speed, said on CBS News’ Face the Nation on Sunday. This could allow more people to receive the vaccine. In a clinical trial, participants aged 18 to 55 who received two 50-µg doses had a similar immune response as those who received two 100-µg doses. Two doses of the 100-µg mRNA-1273 vaccine had 94% efficacy against COVID-19, according to results of the phase 3 trial recently published in the New England Journal of Medicine.

CBS News’ Face the Nation interview with Moncef Slaoui 

FDA briefing document on Moderna’s mRNA-1273 vaccine 

NEJM article on mRNA-1273 vaccine