A coronavirus vaccine developed in the UK can prevent up to 90% of people from getting Covid-19, according to new data.
AstraZeneca and Oxford University announced that their jab is effective in preventing many people getting ill and has been shown to work in different age groups, including the elderly.
One of the dosing patterns used by the scientists suggested 90% effectiveness if one half dose is given followed by a further full dose.
Another dosing pattern showed 62% efficacy when one full dose is given followed by another full dose.
The combined analysis from both dosing regimes resulted in an average efficacy of 70.4%.
Professor Andrew Pollard, chief investigator of the Oxford Vaccine Trial, said: “These findings show that we have an effective vaccine that will save many lives.
“Excitingly, we’ve found that one of our dosing regimens may be around 90% effective and, if this dosing regime is used, more people could be vaccinated with planned vaccine supply.”
Sarah Gilbert, professor of vaccinology at the University of Oxford, added: “The announcement today takes us another step closer to the time when we can use vaccines to bring an end to the devastation caused by [Covid-19].
“We will continue to work to provide the detailed information to regulators. It has been a privilege to be part of this multi-national effort which will reap benefits for the whole world.”
The UK has placed orders for 100 million doses of the Oxford vaccine – enough to vaccinate most of the population – with rollout expected in the coming weeks if the jab is approved.
It also has orders for 40 million doses of a jab from Pfizer and BioNTech, which has been shown to be 95% effective.
Another jab from Moderna is 95% effective, according to trial data.
AstraZeneca chief executive Pascal Soriot said: “Today marks an important milestone in our fight against the pandemic.
“This vaccine’s efficacy and safety confirm that it will be highly effective against Covid-19 and will have an immediate impact on this public health emergency.
“Furthermore, the vaccine’s simple supply chain and our no-profit pledge and commitment to broad, equitable and timely access means it will be affordable and globally available, supplying hundreds of millions of doses on approval.”
Business secretary Alok Sharma said the results were “very promising”.
He tweeted: “Very promising data from the Oxford/AstraZeneca Phase III clinical trials.
“We are on the cusp of a huge scientific breakthrough that could protect millions of lives. The UK has secured early access to 100 million doses of their vaccine – on top of 255 million doses from other developers.”
Health secretary Matt Hancock called the data “really encouraging news”, but stressed that vaccines need to be approved by the Medicines and Healthcare products Regulatory Agency (MHRA).