Novavax's COVID-19 shot effective against UK strain

Novavax’s COVID-19 vaccine could be added to the UK’s growing arsenal of shots against the disease after it showed 89.3% efficacy in a late-stage trial.

The shot is the first to show efficacy against the new variant found in the UK which accounted for around half of cases in the phase 3 study.

Efficacy against the original COVID-19 strain was calculated at around 95.6%, falling to to around 85.6% against the UK variant strain, based on a post-hoc analysis.

But its efficacy was 60% when tested against the variant found in South Africa in a separate phase 2b trial.

The UK government has 60 million doses of the vaccine on order if approved by regulators and much of the shot will be manufactured at Novavax’s UK factory in Billingham, Stockton-on-Tees.

Based on a copy of the spike protein seen on the surface of the coronavirus, the Novavax vaccine is easier to handle than mRNA shots from Pfizer/BioNTech and Moderna.

The Novavax shot is stable at refrigerator temperatures and does not need to be stored in ultra-cool refrigerators needed to keep mRNA vaccines stable.

Novavax said that the MHRA began a rolling review of the vaccine in mid-January, adding that it will share further trial results and data as soon as they become available.

The UK regulator has been fast with its reviews and was the first in the world to approve rival vaccines from Pfizer/BioNTech and AstraZeneca.

The US biotech said that its vaccine met its primary endpoint in a phase 3 clinical trial with an efficacy of 89.3%, on a par with vaccines from Pfizer/BioNTech and Moderna that have shown up to 95% efficacy in phase 3 trials.

Novavax’s figures are also better than the figures of around 70% seen with the AZ/Oxford University vaccine, although this could be improved by changing the formulation.

The UK phase 3 study assessed efficacy during a period with high transmission and with a new UK variant strain of the virus emerging and circulating widely.

The study enrolled more than 15,000 participants between 18-84 years of age, including 27% over the age of 65.

The first interim analysis is based on 62 cases, of which 56 cases of COVID-19 were observed in the placebo group versus 6 cases observed in the NVX-CoV2373 group, resulting in a point estimate of vaccine efficacy of 89.3%.

The interim analysis included a preliminary review of the safety database, which showed that severe, serious, and medically attended adverse events occurred at low levels and were balanced between vaccine and placebo groups.

The phase 2b study in South Africa involved 4,400 patients and began in August 2020, with COVID-19 cases counted from September through mid-January. Nearly 93% of cases were attributed to the triple mutant variant that emerged in the country.

Health Secretary Matt Hancock said the vaccine would be a “significant boost” to the UK’s vaccination programme.

He added: “The NHS stands ready to roll this vaccine out as quickly as possible to those most at risk if it is authorised."