A single-shot coronavirus vaccine from pharmaceutical giant Johnson & Johnson has been approved for use in the UK, with the first delivers expected later this year.
Britain has ordered 20 million doses of the Janssen vaccine, which health officials previously said could be used for hard-to-reach groups of people.
The Janssen jab has been shown to be 67 per cent effective overall at preventing moderate to severe Covid-19. with studies suggesting the vaccine also offers complete protection from admission to hospital and death.
The UK's Medicines and Healthcare products Regulatory Agency (MHRA) approved the safety of the jab, giving Britain four vaccines that have been approved for use under the biggest vaccination programme in UK history.
The others are vaccines developed by Pfizer-BioNTech, Oxford-AstraZeneca and Moderna.
Prime Minister Boris Johnson tweeted: “This is very welcome news and another boost to our hugely successful vaccination programme.
“As we encourage everyone to get their jabs, the single-dose Janssen vaccine will play an important role in helping us protect people from the virus. When you get the call, get the jab.”
Health Secretary Matt Hancock said: “This is a further boost to the UK’s hugely successful vaccination programme, which has already saved over 13,000 lives, and means that we now have four safe and effective vaccines approved to help protect people from this awful virus.
“As Janssen is a single-dose vaccine, it will play an important role in the months to come as we redouble our efforts to encourage everyone to get their jabs and potentially begin a booster programme later this year.”
Vaccines Minister Nadhim Zahawi added: “The Janssen vaccine will be another weapon in our arsenal to beat this pandemic.
“We are doing everything we can to vaccinate all adults as quickly as possible and I encourage everybody to come forward for a jab as soon as they are eligible.”
The Government said the vaccination programme "continues at pace" and remains "on track" to offer a jab to all adults by the end of July.
Professor Jonathan Van-Tam, has previously said could be used for hard-to-reach groups of people, where recalling them for a second jab is not always successful.
The independent Commission on Human Medicines (CHM) reviewed and endorsed the MHRA’s decision.
The MHRA is thought to have held back from early approval of Janssen vaccine after concerns were raised in the US about a link to extremely rare blood clots.
The clots are similar to those seen in a very small proportion of people having the Oxford/AstraZeneca jab.
In April, the European Medicines Agency said a warning about unusual blood clots with low blood platelet count should be added to the product information for the vaccine.
This followed eight cases of blood clots in more than seven million people vaccinated in the US.
Johnson & Johnson has said the vaccine works across multiple variants of coronavirus.
In a clinical trial involving 43,783 people, published earlier this year, the level of protection against moderate to severe Covid-19 infection was found to be 72 per cent in the United States arm of the trial.
It was 66 per cent in the Latin American arm of the trial, and 57 per cent in the South African arm, where a mutant variant of the virus has been dominating.
The overall efficacy from these trials combined was 67 per cent.
The vaccine was also found to be 85 per cent effective in preventing severe disease or hospitalisation, the UK Government said.
It can be stored at fridge temperatures, between 2C and 8C, "making it ideal for distribution to care homes and other locations across the UK", the Government said.
How does the Johnson & Johnson vaccine work?
The Johnson & Johnson (J&J) vaccine is the fourth coronavirus jab approved for use in the UK.
But how does it work, and what does it do?
What kind of vaccine is it?
Developed by Johnson & Johnson’s pharmaceutical arm, Janssen, the jab is an adenovirus vaccine.
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.
How does it work?
Like the Oxford/AstraZeneca jab, the J&J vaccine uses viral vector technology where a modified version of a different virus is used to deliver instructions to the body’s cells to trigger the immune system to begin producing antibodies.
How many doses has the UK ordered?
The UK has ordered 20 million doses of the single-dose jab.
The Vaccine Taskforce originally secured 30 million doses, based on the predicted clinical need at the time.
But given the scale and pace of the vaccine rollout in the UK the government has decided to amend its original order.
The first deliveries are expected to arrive in the country from later this year now the jab has been authorised by the Medicines and Healthcare products Regulatory Agency (MHRA).
But were there not concerns about the vaccine being linked to blood clots?
The European Medicines Agency (EMA) said there is a “possible link” between Johnson & Johnson’s Covid-19 vaccine and very rare blood clots.
But it concluded that the overall benefits of the vaccine “outweigh the risks of side effects”.
J&J previously confirmed it would delay rollout of its single-dose vaccine across Europe after the US paused its administration to investigate reports of potentially dangerous blood clots.
The Joint Committee on Vaccination and Immunisation (JCVI) will submit updated advice for the Janssen vaccine before doses become available.
What other vaccines does the UK have?
So far the Moderna, Pfizer/BioNTech and Oxford/AstraZeneca vaccines are being administered in the UK.
The approval of the J&J vaccine comes as it is thought that the most vulnerable groups of people, including the elderly, will be offered a booster jab before next winter.
Dr June Raine, chief executive of the Medicines and Healthcare products Regulatory Agency (MHRA), said of the approval of the Janssen vaccine: “This is encouraging news for the public and the healthcare sector.
“We now have four safe and effective vaccines approved to help protect us from Covid-19.
“Our work does not end here. We are continually monitoring all Covid-19 vaccines in use once they have been approved to ensure that the benefits in protecting people against the disease continue to outweigh any risks.
“The safety of the public will always come first – you can be absolutely sure of our commitment to this.”
