The news: US company Novavax has today announced that its covid-19 vaccine was found to be 89% effective in final-stage clinical trials in the UK. It discovered the vaccine protects people with the UK covid-19 variant, known as B.1.1.7, but is less effective against the variant sequenced in South Africa, known as B.1.351.
The details: The Phase 3 trials enrolled more than 15,000 people aged between 18 and 84. The Novavax vaccine, which requires two doses, was 86% effective against the UK variant, but in the South African wing of the trial, where most people had the South African covid-19 variant, the vaccine was just 50% effective (similar to the level of protection conferred by most flu vaccines.) The UK has bought 60 million doses of the vaccine which will be produced locally. Novavax is a small US company that received $1.6 billion from the US government as part of “Operation Warp Speed.”
The (concerning) bigger picture: Novavax is not the only vaccine maker to discover its covid-19 shot is less effective against the South African variant. Moderna and Pfizer recently reported that their vaccines don’t work as well against this variant either, although manufacturers are confident that they would be able to quickly produce updated versions to combat the changing virus. The US reported its first known cases of the South African variant yesterday in two people in South Carolina. Those people had not had contact with one another, which suggests B.1.351 may already be spreading throughout the community in parts of the US.
Still waiting: Another vaccine trial should soon give us more data on whether vaccines can tackle the South African variant. Johnson and Johnson conducted a large trial for its single-shot vaccine that recruited thousands of South Africans between September and December, just as the dangerous variant spread widely. Scientists will want to see if the shot is less effective in South Africa than it has been in the US, where part of the trial occurred. That trial data is due to be released any day now.