Novavax says its Covid-19 vaccine is 90% effective, but far less so against one variant
A Covid-19 vaccine from Novavax proved nearly 90% effective in preliminary results from a key clinical trial in the United Kingdom, the company said, but appeared far less effective against a new variant of the coronavirus that accounted for most of the cases in South Africa.
In its 15,000-volunteer U.K trial, Novavax said, the vaccine prevented nine in 10 cases, including against a new strain of the virus that is circulating there. But in a separate 4,400-volunteer study in South Africa, the vaccine proved only 49% effective. In the 94% of the study population that did not have HIV, the efficacy was 60%.
