Novavax says Covid-19 vaccine 89 per cent effective in UK trial; Johnson welcomes result

US biotech firm Novavax has said that its coronavirus vaccine was 89.3 per cent effective in preventing Covid-19 in a trial conducted in the UK, and was nearly as effective in protecting against the more highly contagious variant first discovered in the UK, according to a preliminary analysis.

A mid-stage trial of the vaccine in South Africa, where a troubling new variant of the virus is common, showed 60 per cent effectiveness among people who did not have HIV.

British prime minister Boris Johnson described the report as 'good news'

"Our medicines regulator will now assess the vaccine, which will be made in Teesside. If approved, we have 60m (million) doses on order," Johnson said on Twitter.

Novavax is already stockpiling vaccine at six operating manufacturing locations, and said it expects a total of eight plants in seven countries to produce at the rate of 2 billion doses per year, including from the Serum Institute of India.

The company on a conference call noted that this was interim data and executives said they expect it will be two to three months before they are ready to apply for authorisation with regulators.

The UK trial, which enrolled 15,000 people aged 18 to 84, is expected to be used to apply for use in Britain, the EU and other countries.

Approval of the Novavax vaccine would be most welcome in Europe as it struggles with meager vaccine supply after Pfizer/BioNTech and AstraZeneca Plc delivered fewer doses than hoped.

Executives on the call said the company was discussing with the US Food and Drug Administration whether the UK and South Africa data was enough to apply for US emergency use authorisation.

The UK study took place as the more highly transmissible UK variant was circulating. The preliminary analysis suggests the vaccine was 85.6 per cent effective against this mutation, the US company announced in its news release. It did not provide detailed data.

In the UK trial, the effectiveness of the vaccine was close to that of the two authorised vaccines from Pfizer Inc with BioNTech SE and Moderna Inc, whose two-dose regimens were both around 95 per cent effective at preventing Covid-19 in clinical trials.

Novavax said it started making new versions of its vaccine to protect against emerging virus variants in early January and expects to select ideal candidates for a booster in the coming days. The company said it plans to initiate clinical testing of these new vaccines in the second quarter of this year.

A 30,000-person trial in the US and Mexico that began in December also is underway. The company has received $1.6 billion from the US government in funding for the vaccine trial and for 100 million doses.

It also has received at least $388 million in backing from the Coalition for Epidemic Preparedness Innovation (CEPI), a Norway-based group backed by 14 governments, the Bill and Melinda Gates Foundation, and Britain’s Wellcome Trust.

Novavax’s is a more conventional protein-based vaccine, an approach similar to that used by Sanofi to make its Flublok seasonal flu vaccine. The Novavax vaccine works with the company's proprietary Matrix-M adjuvant used to boost its efficacy.