Novavax vaccine 96% effective against original virus in UK trial

LONDON • Novavax's Covid-19 vaccine was 96 per cent effective in preventing cases caused by the original version of the coronavirus in a late-stage trial conducted in Britain, the company said on Thursday, moving it a step closer to regulatory approval.

There were no cases of severe illness or deaths among those who received the two-shot vaccine, a sign that the shot could stop the worst effects of the new virus variants.

The vaccine was 86 per cent effective in protecting against the more contagious variant prevalent in Britain, for a combined 90 per cent effectiveness rate overall based on data from infections of both versions of the coronavirus.

In a smaller trial in South Africa - where volunteers were primarily exposed to another more contagious variant widely circulating there - the Novavax shot was 55 per cent effective, based on people without HIV, but still fully prevented severe illness.

Novavax chief medical officer Filip Dubovsky said the performance in South Africa suggests there may still be a case for using it in areas where the South African variant is dominant.

Novavax is also developing new formulations of its vaccine to protect against emerging variants.

The company plans to use its latest data to submit for regulatory authorisation in various countries. It expects more data from a 30,000-person trial in the United States and Mexico by early next month. It is not clear if US regulators will require it to complete the ongoing US trial before granting approval for use.

The vaccine could be cleared for use in the US as soon as May if US regulators decide the British data is enough to make a decision.

The British trial, which enrolled more than 15,000 people aged 18 to 84, assessed efficacy of the vaccine during a period with high transmission of the British virus variant now circulating widely.

The shot's effectiveness in the South Africa trial declined to around 49 per cent when the analysis included data from HIV-positive participants.

Novavax's production plants should all be fully functional by next month, executives have said. The firm plans to produce its vaccine at eight manufacturing locations, including the Serum Institute of India.

REUTERS