The UK drugmaker also said that adverse reactions were lower among the elderly, Britain's Financial Times newspaper reported The vaccine triggers protective antibodies on T cells in older age groups.

T cell immunity is thought to be essential to protection against infection from the virus and could provide longer term immunity than antibodies.

Blood tests carried out on a set of older participants reflected data released in July which showed the vaccine did generate quote robust immune responses in healthy adults aged 18 to 55.

AstraZeneca said that it was encouraging to see the immune responses were similar between both older and younger adults.

They also claimed the results further built the body of evidence for the safety and effectiveness of their drug.

AstraZeneca has worked with University of Oxford researchers this year on a vaccine, and it's seen as a global front runner in the race to produce one.

British Health Secretary Matt Hancock said a vaccine was not yet ready, but he was preparing logistics for a possible rollout.

He added he expected this to happen in the first half of 2021.

Astra Zeneca shares rose around nor 20210.8% in early trade Monday, defying a down day for broader markets.