The Novavax vaccine could be “desirable” for future booster campaigns, experts have said.
New clinical trial results showed the jab was 100% effective against preventing moderate or severe disease.
Britain has ordered 60 million doses of the vaccine.
The firm said that it will be filing for regulatory approval by medicines regulators in the third quarter of the year.
It started a rolling review process with the UK regulator, the Medicines and Healthcare products Regulatory Agency (MHRA), in January.
It comes as the firm produced positive results from its clinical trial in the US and Mexico.
Almost 30,000 were enrolled in the Prevent-19 trial, which concluded that the vaccine is 90.4% effective overall and 100% effective against preventing moderate or severe disease.
Officials said that the findings also “reaffirm the ability of the vaccine to prevent Covid-19 amid ongoing genetic evolution of the virus” amid growing concern about new variants.
The vaccine was also reported to be “well tolerated” with some participants reporting injection site pain and tenderness, and fatigue, headache and muscle pain.
The two-dose vaccine works in a different way to the jabs currently being used in the UK. It combines an engineered protein from the virus that causes Covid-19 with a plant-based ingredient to help generate an immune response.
Dr Gregory Glenn, president of research and development at Novavax, told a briefing for journalists that the company was having “very active, constructive” discussions with the MHRA.
On the mix and match studies in the UK – which are testing out a combination of different vaccines – he said: “They are looking at the safety and immunogenicity and I think (the researchers) are going to submit a letter to The Lancet on the safety so look for that this week.
“Overall our safety profile is very desirable for boosting.”
He added: “We’re aware of this timing need for boosting in the UK and we certainly have that in our sights and if at all possible that we can be involved in that we would like to be.
“What I can say as a vaccinologist and immunologist is that we are going to see immunity wane and you’re going to need a boost. I think the UK is rightly, from a public health standpoint, presuming that you’re going to need to boost people.
“Our vaccine is a recombinant vaccine, those are licenced, there is a tonne of experience with that from a safety standpoint as a platform.
“As people go out and start to contemplate the next step a lot of them will pay attention to the safety profile and I think our vaccine gives them a desirable option.”
He added that clinical trials had provided “incredible confirmation” that the vaccine was working well.
“I think that’s going to be important information for those conducting boosting campaigns as well as for people who are selecting what they want to have done with their arm,” he said.
Asked about new variants, he added: “We’re trying to be ready – our technology allows us to make different vaccines.
“I do think this is encouraging, it looks like high-quality antibodies cover a lot of variation.”
Paul Heath, professor of paediatric infectious diseases and director of the Vaccine Institute at St George’s, University of London and St George’s Hospital, London, and chief investigator of the Novavax UK trial, said: “These preliminary results from the large US/Mexico Prevent-19 trial confirm the high efficacy and safety of the Novavax Covid-19 vaccine shown earlier in the year in the UK Novavax Vaccine Trial (an overall efficacy of 89%).
“The results are very reassuring and importantly show that this vaccine appears to be safe and effective in populations from a range of communities and demographic groups, and those with a range of underlying comorbidities, now (across both trials) with a total number of participants of more than 45,000.
“Both the UK and US/Mexico trials used the same case definitions, and these consistent results therefore provide much confidence in the use of this vaccine for the global population.
“We now await the peer-reviewed publication. We also look forward to the results of the trial’s adolescent arm – 12 to 17 years of age – which recently completed enrolment.”
Two sites have been enlisted to the production process in the UK for part of the manufacturing process for the jab – FUJIFILM Diosynth Biotechnologies’s facilities in Billingham, Stockton-on-Tees and the GSK site at Barnard Castle.