Novavax’s Covid-19 vaccine was 90 per cent effective in its late stage trial in the US and Mexico and proved it can tackle the virus variants of concern, opening the way for the approval of another shot to control the pandemic.

The Maryland-based company — which after 33 years, has not yet had a product approved — said its vaccine offered 100 per cent protection against moderate and severe Covid-19. All cases of Covid-19 in the vaccinated group were mild. 

The two-dose vaccine showed 93 per cent efficacy against the variants of concern and the emerging variants of interest, which represented the vast majority of cases. It was 91 per cent effective for people in high risk groups, such as the over-65s and those suffering from underlying conditions.