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FRIDAY, March 12, 2021 (HealthDay News) -- A COVID-19 vaccine developed by Novavax was 96 percent effective against the original strain of the coronavirus in preventing mild, moderate, and severe cases of illness and was 100 percent effective against severe disease caused by new, more contagious variants, two new clinical trials show.
However, its effectiveness against mild and moderate illness fell to 86 percent against the B.1.1.7 variant first detected in the United Kingdom and to 55 percent against the B.1.351 variant that has become dominant in South Africa, The Washington Post reported.
The new findings, which have not been peer-reviewed or published yet, support an interim analysis released in January.
"A trend we're seeing, even with these variants, is that these vaccines are retaining high efficacy against severe disease," said Kathleen Neuzil, M.D., director of the Center for Vaccine Development and Global Health at the University of Maryland School of Medicine in Baltimore. "I really loved seeing the 100 percent efficacy against severe disease."
The company said it will present the data to regulatory agencies worldwide, including the U.S. Food and Drug Administration. A large, 30,000-person trial is ongoing in the United States and Mexico.