Covid vaccine: Single-dose Johnson & Johnson jab is 66% effective

Dr Claire Cole from Manchester University NHS Foundation Trust volunteered in the Janssen jab's Phase 3 trial

A new single-dose vaccine has shown to be 66% effective against Covid-19, and offered complete protection against hospitalisation and death in trials.

However, there are signs the jab, made by Belgian pharmaceutical firm Janssen, is less effective against the new variant spreading in South Africa.

The Johnson & Johnson-owned company is looking at whether two doses will give stronger or longer-lasting protection.

It aims to make one billion doses this year.

The UK has ordered 30 million doses, the US 100 million and Canada 38 million.

UK Health Secretary Matt Hancock said if the jab was approved by Britain's Medicines and Healthcare Products Regulatory Agency (MHRA) it could "significantly bolster" the country's vaccine programme.

Crucially, no one needed hospital treatment or died from coronavirus after the Janssen vaccine took effect in the international trial.

The news comes shortly after Novavax announced their jab was 89% effective overall in the UK and 60% in South Africa. Both new vaccines will need to be reviewed by regulators before they can be used.

Meanwhile, the EU's drugs regulator has approved the use of the AstraZeneca vaccine for people aged over 18.

It comes amid an ongoing dispute over whether AstraZeneca is breaking its vaccine delivery commitments to the bloc, which has seen the EU confirm that it will bring in export controls on Covid vaccines made in the bloc.

The EU has temporarily overridden a section of the Brexit deal in relation to Northern Ireland, over concerns the country could become a backdoor for vaccines from the EU to be sent into the wider UK.

Arlene Foster, DUP leader and Northern Ireland's first minister, called the move "an incredible act of hostility" by the EU.

It comes as the UK reported a further 29,079 new coronavirus cases on Friday, and 1,245 deaths within 28 days of a positive coronavirus test in the government's daily figures, bringing the total deaths by that measure to 104,371.

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Crucially, the Janssen trial looked at giving just one dose of the vaccine, which makes it significantly easier to roll out than those requiring two. It is also investigating whether giving two doses will give either stronger or longer-lasting protection.

The fact it works as a single dose and can be kept in a standard fridge, while others need super-cold storage, means the vaccine could have a significant role around the world.

"A one-shot vaccine is considered by the World Health Organization to be the best option in pandemic settings," said Dr Paul Stoffels, the chief scientific officer at Johnson & Johnson.

He added the vaccine could "potentially protect hundreds of millions of people from serious and fatal outcomes of Covid-19".

It is easy to become complacent after the astounding success of the first vaccines to go through trials.

But having another two effective vaccines is a cause for massive celebration.

It will take vast quantities of vaccine to immunise the world - remember this is a pandemic - and the more options we have available, the better.

However, there is also a warning sign in the new data from the Janssen and Novavax trials.

Both showed a dip in their overall effectiveness in South Africa, where a new and worrying variant has been spreading.

The results from South Africa were still good and clearly better than no vaccine at all.

But they do emphasise how coronavirus is a moving target and that we may need to change the vaccines we use in the future.

The Janssen vaccine uses a common cold virus that has been engineered to make it harmless.

It then safely carries part of the coronavirus's genetic code into the body. This is enough for the body to recognise the threat and then learn to fight coronavirus.

This trains the body's immune system to fight coronavirus when it encounters the virus for real.

This is similar to the approach used by the University of Oxford and AstraZeneca.

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Dr Mathai Mammen, from Janssen, said: "A single dose regimen with fast onset of protection and ease of delivery and storage provides a potential solution to reaching as many people as possible.

"The ability to avoid hospitalisations and deaths would change the game in combating the pandemic."

The results are based on nearly 44,000 people who took part in the trial and 468 cases of Covid-19.

However the vaccine was just 57% effective in the South African part of the trial, where a new version of the coronavirus is spreading, compared with 72% in the US.

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Prime Minister Boris Johnson said that the results from the early trials were "very encouraging", and if the vaccine was approved doses should be available later this year.

Mr Hancock said the Janssen announcement was "yet more good news".

"If this jab is approved this could significantly bolster our vaccination programme, especially as a single-dose vaccine," he said.

"Once the full data has been submitted [to the MHRA], they will consider the evidence to determine whether the vaccine meets robust standards of safety, effectiveness & quality."

In the UK, the latest estimate for the R rate from the government's scientific advisory group, Sage, is 0.7 to 1.1. It means that on average, every 10 people with the virus will infect between seven and 11 other people. Last week, the R rate was between 0.8 and 1.

The number of coronavirus cases in the UK remained virtually unchanged in the week to 23 January, according to Office for National Statistics (ONS) data. Its survey suggests the epidemic is levelling off or perhaps very slightly falling - but not at the rate hoped.

More than 7.8 million people in the UK have so far received a first dose of a coronavirus vaccine, according to the latest government figures.

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