Novavax surges 12% as its COVID-19 vaccine is found to be 96% effective in preventing the original virus strain

• Novavax shares rose 12% in regular trading Friday after the company announced its vaccine efficacy.
• The company's vaccine, NVX-CoV2373, was found to be 96.4% effective against the original strain of COVID-19.
• It is 86.3% effective against the more contagious virus strain found in the UK.

Shares in Novavax rose as much as 20% in pre-market trading Friday after the company announced its coronavirus vaccine candidate is 96.4% effective against the original strain of the COVID-19 virus in a third-stage trial conducted in the UK.

The announcement brings the US-based company closer to getting its vaccine, NVX-CoV2373, approved for use by regulators.

Novavax said its vaccine is 86.3% effective against the more contagious virus variant found in the UK. The study enrolled more than 15,000 participants aged between 18 and 84.

In a smaller trial conducted in South Africa, the company said its vaccine was 55% effective against another contagious variant in volunteers without HIV, but still prevented severe illness. The shot's effectiveness fell to around 49% when the analysis included data on participants who were HIV-positive, according to Reuters.

"Across both trials, NVX-CoV2373 demonstrated 100% protection against severe disease, including all hospitalization and death," Novavax said in a statement.

The company's shares rose 22% in pre-market trading to $235.71 per share. They were trading below $10 in January 2020 when it announced it was developing a vaccine.

Novavax is planning to file for vaccine authorization from UK regulators early in the second quarter of 2021, the company's chief medical officer Filip Dubovsky told Reuters. It plans to produce its two-shot vaccine in eight locations, including at the Serum Institute of India in Pune.