Novavax vaccine protects against coronavirus in variant hot spots but proved less effective against strain in South Africa

A coronavirus vaccine made by Maryland biotech company Novavax proved effective at stopping symptomatic infections in global hot spots where concerning variants are dominant, the company announced Thursday. But warning signs lurked amid those findings: The protective effect of the vaccine was substantially muted in South Africa, where a worrisome virus variant is in wide circulation.

The data, presented by a company news release, is ominous news for other vaccine developers. They have been scrambling to determine whether current vaccines would remain effective against the variant found in South Africa and are designing new versions in case the virus can break through the protection provided by the shot. The data is the first, highly anticipated evidence of how well a vaccine performs against variants that have drawn global concern.