How do the Novavax and Johnson & Johnson vaccines compare?

The two jabs are not as efficacious as their rivals but widen the pool of doses that will be available to the world

Two more vaccines have been shown to be effective in providing protection against Covid-19 - the latest breakthrough against a disease that has now infected more than 100 million people globally.

The vaccines manufactured by Johnson & Johnson and Novavax are not as efficacious as their rivals but widen the pool of doses that will be available to the world.

So, how do they compare?

Type

Novavax: Protein adjuvant (two doses)

This technology is tried and tested for generating effective vaccines. Modern flu vaccines, HPV vaccines, and HepB vaccines all use a similar approach.

It’s a protein subunit vaccine, which means that it contains a lab-made version of the Sars-CoV-2 spike protein. This spike protein alone can’t make anyone sick.

But to make sure that the body still generates the protective antibodies against it, Novavax has inserted an ingredient called an adjuvant, which also works to enhance the response of the immune system.

This component has been shown to create a stronger and longer lasting immunity against infections than the vaccine alone. It can also reduce the amount of vaccine protein required per dose, which allows more to be produced.

Johnson & Johnson: Adenovirus (one dose)

These are based on weakened versions of adenoviruses, which are a group of viruses that typically infect membranes of the eyes, respiratory tract, urinary tract, intestines and nervous system, and include the common cold.

The adenovirus vector is genetically engineered to carry DNA from Sars-CoV-2 into the human body, which then codes for the spike protein. The immune system spots this and springs into action to produce the necessary protective response.

The Oxford vaccine makes use of the same technology.

Efficacy

Novavax

Data shows the new Novavax vaccine is 89 per cent effective at preventing Covid-19 in a clinical trial run in the UK, which involved more than 15,000 people aged between 18-84, of which 27 per cent were older than 65.

More than 50 per cent of cases related to the UK strain of the virus first identified in Kent, with the vaccine offering 86 per cent protection against this strain.

Against the original strain that has circulated since the start of the pandemic, the vaccine was 96 per cent effective.

In a separate South African arm of the trial, where most cases of Covid-19 were the worrying South African strain, the jab was 60 per cent effective in people without HIV.

Johnson & Johnson

The single-shot vaccine, which has been developed by Johnson & Johnson's pharmaceutical arm Janssen, is 66 per cent effective overall at preventing moderate to severe Covid-19 28 days after vaccination.

The firm said the jab was 85 per cent effective in preventing severe disease "and demonstrated complete protection against Covid-19-related hospitalisation and death as of day 28".

Johnson & Johnson conducted trials in multiple countries as part of its large-scale study – all of which showed some discrepancies in results. While the jab’s efficacy rate stood at 57 per cent in South Africa, where a new variant of coronavirus is rampant, it was slightly higher in Latin America, at 62 per cent, and higher still in the US, at 72 per cent.

Storage and transportation

Novavax

Doses can be kept at fridge temperatures. It’s expected to last at least six months in these conditions, although work on this is ongoing.

It can also be made using existing bioreactor equipment already widely available to manufacturing plants.

Distribution is expected to be worldwide once approved.

Johnson & Johnson

The vaccine does not require ultra-cold temperatures for transportation and storage. Instead it can be kept at 2-8C for up to three months.

It is also cheap, costing about £7 a dose, offering hope to poorer nations currently struggling to obtain vaccines.

Distribution is expected to be worldwide once approved.

Supplies

Novavax

Britain has secured 60 million doses of the Novavax jab - to be produced on Teesside - with the hope that the Medicines and Healthcare products Regulatory Agency (MHRA) could approve it within weeks.

The firm intends to produce 1bn to 2bn doses throughout 2021, and will be manufactured in the US, Czech Republic, Spain, Sweden, Denmark and South Korea.

Johnson & Johnson

The UK has pre-ordered 30 million doses of the vaccine, with the option of 22 million more. Deliveries are expected in the second half of this year if the jab is approved.

A total of one billion doses are expected to be manufactured globally throughout 2021.