Trials suggest Oxford Covid-19 vaccine works in all ages

Oxford University's Covid-19 experimental vaccines produced an immune response in both older and young adults, raising hopes of a path out of the gloom and economic destruction wrought by the novel coronavirus.

British drugmaker AstraZeneca, which is helping to manufacture the vaccine, on Monday said that vaccine also triggers lower adverse responses among elderly people, reports the Guardian.

A vaccine that works is seen as a game-changer in the battle against coronavirus, which has killed more than 1.15 million people, shuttered swathes of the global economy and turned normal life upside down for billions of people.

"It is encouraging to see immunogenicity responses were similar between older and younger adults and that reactogenicity was lower in older adults, where the Covid-19 disease severity is higher," an AstraZeneca spokesman said.

"The results further build the body of evidence for the safety and immunogenicity of AZD1222," the spokesman said, referring to the technical name of the vaccine.

AstraZeneca did not provide detail of the data behind the statement or say when it would publish eagerly awaited late-stage phase 3 trial data, which would show whether the vaccine works well enough in large-scale trials for it to be approved.

The vaccine is expected to be one of the first from big pharma to secure regulatory approval, along with one from Pfizer and BioNTech.

The news that older people get an immune response from the vaccine is positive because the immune system weakens with age and older people are those most at risk of dying from the virus.

If it works, a vaccine would allow the world to return to some measure of normality after the pandemic.

British Health Secretary Matt Hancock said a vaccine was not yet ready but he was preparing logistics for a possible rollout, mostly in the first half of 2021.

Asked if some people could receive a vaccine this year, he told the BBC: "I don't rule that out but that is not my central expectation."

Work began on the Oxford vaccine in January. Called AZD1222 or ChAdOx1 nCoV-19, the viral-vector vaccine is made from a weakened version of a common cold virus that causes infections in chimpanzees.

Immunogenicity blood tests carried out on a subset of older participants echo data released in July that showed the vaccine generated "robust immune responses" in a group of healthy adults aged between 18 and 55, the Financial Times reported earlier.

"We need to see the data before concluding that the responses were 'similar'," said Stephen Evans, a professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine.

He said that reactogenecity – the common side-effects of vaccines such as soreness and redness of the arm – was "often, but not always" associated with a vaccine's immunogenicity.

"Studies carried out in the first stage of development of a vaccine will result in choosing a dose that does not cause too much reactogenicity," he said.

AstraZeneca has signed several supply and manufacturing deals with companies and governments around the world as it gets closer to reporting early results of the late-stage clinical trial.

It resumed the US trial of the experimental vaccine after approval by US regulators, the company said on Friday.

Staff at a London hospital trust have been told to be ready to receive the first batches of the Oxford-AstraZeneca vaccine, the Sun reported on Monday.