Early results from tests for a coronavirus vaccine being developed by the University of Oxford, in collaboration with AstraZeneca Plc, show it produces a robust immune response in elderly people, the group at highest risk, the Financial Times reported on Monday.

It has been discovered that the vaccine triggers protective antibodies and T-cells in older age groups, the newspaper said on.ft.com/3kxKyJI, citing two people familiar with the finding, encouraging researchers as they seek evidence that it will spare those in later life from serious illness or death from the virus

The findings echo data released in July which showed the vaccine generated “robust immune responses” in a group of healthy adults aged between 18 and 55, the newspaper reported, citing people aware of the results from so-called immunogenicity blood tests.

But the FT cautioned that positive immunogenicity tests do not guarantee that the vaccine will ultimately prove safe and effective in older people.

AstraZeneca, which is developing the vaccine with Oxford University researchers, is seen as a frontrunner in the race to produce a vaccine to protect against Covid-19.

Details of the finding are expected to be published shortly in a clinical journal, the FT said, without naming a journal.

Oxford and AstraZeneca did not immediately respond to Reuters’ request for comments.

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