Maryland-based biotech company Novavax reported Thursday that its experimental Covid-19 vaccine is more than 96 percent effective in preventing mild and serious illnesses.
The results come from the company’s Phase 3 clinical trial, which was continued in the UK Novavax’s trials in the US and South Africa, and the company cannot apply for permission for emergency use in the US before the US trials have not been completed.
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“We are very encouraged by the data,” said Stanley Erck, Novavax’s president and CEO, in a statement.
The British trial included more than 15,000 adults. More than a quarter were 65 or older, an age group generally considered to be at higher risk for Covid-19 complications.
The dual-dose vaccine has been found to be more than 96 per cent effective against the earlier virus strains spreading in the UK, and it is on the same level as vaccines already used by Moderna and Pfizer-BioNTech.
The effectiveness was slightly lower – about 86 per cent – compared to the more contagious B.1.1.7 variant, which was first identified in the UK. The variant has already been detected in almost half of the US states, and the Centers for Disease Control & Prevention has predicted that it will be the predominant variant by the end of the month.
The Novavax vaccine was also 100 percent effective against the most severe forms of Covid-19, regardless of the variant – just like the other vaccines used in the US.
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By the end of May, the Biden administration had promised enough vaccine to all Americans. The target is expected to be achieved with already available vaccines, from Moderna, Pfizer-BioNTech and Johnson & Johnson.
Other vaccines that ultimately prove to be successful are critical to the health and safety of Americans in a post-Covid-19 environment in which viruses can travel from country to country as fast as airplanes.
“The United States is not safe until the vast majority of the rest of the world is vaccinated,” said John Grabenstein, a former executive director of medical matters for vaccines at Merck and a former defense immunologist.
Novavax also analyzed data from its Phase 2b clinical trial in South Africa, where another SARS-CoV-2 variant did the rounds. The variant, called B.1.351, refers to scientists because it seems to lower the effectiveness of the vaccine. According to Novavax, the vaccine is about 50 percent effective against the variant.
The Novavax vaccine differs slightly from the other vaccines used. The Pfizer, Moderna and Johnson & Johnson vaccines contain instructions for the body to build the coronavirus’ vein protein, which the immune system learns to recognize and fight. The Novavax shot skips the instructions and delivers the vein protein directly to the body.
If it is eventually approved for use, the Novavax shot could serve as another shield we can use to protect against a nasty virus, ‘Grabenstein said.
According to the CDC, more than 98 million doses of vaccine have been administered, and nearly 34 million people have been completely vaccinated.
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