This week American vaccination developer Novavax published the positive results from its UK phase 3 Covid-19 vaccine study. The vaccine has been trialled across five countries and has involved 37,000 participants, but its success across the now diverse variants in these populations has been mixed.

Of the 15,000 UK participants aged 18-84, the results showed that the vaccine is 95.6% effective against the non-variant strain of Covid-19 but goes down to 89.3% against the now predominate and more contagious UK variant.

On the other hand, more concerningly, results from the phase 2 clinical trial in South Africa showed that against the now dominant South African variant the vaccine’s protection plummets to 60.1%, and 49.4% for those whose immune response has been compromised by HIV. As well as the results contained suggestive evidence that a previous infection by the non-variant does not protect against the more recent mutation.

Consequentially, Novavax is developing a new targeted vaccine for the South African variant, to begin clinical trials early this year. Although, the decline in the effectiveness of this vaccine might cause some concerns as to any already approved vaccine’s efficacy against constantly developing new mutations, and in particular to any further spread of the South African strain.

How does this vaccine differ from the previous candidates?

This vaccine differs from many previous candidates, such as the Pfizer or Moderna jabs, which work by injecting the genetic code for the Covid-19 spike protein. Or the Oxford/AstraZeneca vaccine that works by injecting a harmless Chimpanzee common virus containing genetic instructions for the Covid-19 spike protein that causes an immune response once in the body.

However, this vaccine uses nanoparticle technology to encode an engineered protein with the genetic sequence of Covid-19, and it is combined with Novavax’s patented plant-based agent that promotes a more robust immune response in the injection site. But similarly, to the Modern and Oxford vaccines, the Novavax jab is stable at normal refrigeration temperatures and is therefore primed for widespread distribution and is comparatively average in price range at £23.32 for the full treatment.

How has the UK Government responded to the results?

On the announcement of the successful UK phase 3 study, the Government welcomed the results, primarily as the trial was conducted during the spread of the new more virulent UK mutation, and has shown relatively high efficacy against that strain.

While the vaccine is yet to be approved by the Medicine and Healthcare products Regulatory Agency, the Government has already secured 60 million doses enough to immunise 30 million people, due to be delivered in the second half of this year.

Additionally, Novavax last August announced that they would be manufacturing the bulk of this vaccine in the UK; therefore, the Government said that this would ensure that, once available, a supply for the British public will be secure.

Vaccines Minister Nadhim Zahawi said: “Having taken part in Novavax’s vaccine trial myself, I am particularly thrilled to see such positive results. I want to thank the thousands of trial volunteers, without whom these results would not have been possible.”

“It will now be for the regulator to do its crucial work in assessing the efficacy and safety of this vaccine, but if approved, it will be a further boost to our vaccination programme.”