Novavax announced Thursday that its COVID-19 vaccine had proved effective, especially at preventing serious illness or death, in late-stage trials in Britain and South Africa, home to two of the more contagious variants spreading around the world.
The Maryland biotech firm said that its final analysis of its British trial found the vaccine 96 percent effective against the original strain and 86 percent effective against the B.1.1.7 variant, for an overall protection rate of 90 percent. In the smaller South African trial, the vaccine was 55 percent effective at preventing COVID-19 cases among people without HIV, and 49 percent effective when the HIV-positive subset was included. There were zero cases of severe illness in either country among trial participants who got the vaccine, Novavax said, versus 10 severe cases in people given placebos.
"A trend we're seeing, even with these variants, is that these vaccines are retaining high efficacy against severe disease," Kathleen Neuzil, director of the Center for Vaccine Development and Global Health at the University of Maryland School of Medicine, tells The Washington Post. "I really loved seeing the 100 percent efficacy against severe disease."
The results, mostly in line with a preliminary analysis from January, have not yet been peer-reviewed or published. But Novavax says it will submit them to regulatory agencies around the world, including in Britain and the U.S. The company expects its 30,000-person trial in the U.S. and Mexico to wrap up by early April. If the Food and Drug Administration accepts the data from the U.K. study, Novavax says, its vaccine could get U.S. approval as soon as May. Otherwise, it could be several months before the U.S. gives it the green light.