TRIGGERS IMMUNE RESPONSE

Oxford vaccine effective in people above 70 years

It is also being tested in Kilifi to see if it prevents people from getting Covid-19

In Summary

•The results come from two trial sites in the UK where the participants were enrolled between May 30 and August 8, 2020.

•According to Kemri-Wellcome Trust, Phase III trial is partly being conducted in Kenya because a vaccine which works in one population does not necessarily work in all populations.

A medic holds a bottle labelled Vaccine Covid-19.
VACCINE TRIALS: A medic holds a bottle labelled Vaccine Covid-19.
Image: REUTERS

The latest trial results from the University of Oxford Covid-19 vaccine suggest that it produces a strong immune response in older people.

The results published in Lancet journal from the Phase II trial carried out in the UK, indicate that the vaccine triggers a robust immune response in healthy adults aged 56-69 and over 70 years.

Researchers said they had already demonstrated the vaccine triggers immune response in young people.

This is the first time they are demonstrating that the vaccine is equally effective in older people, who usually have poor response due to the natural degeneration of the immune system.

The finding is important because older adults aged above 70 years are at increased risk of severe disease and death if they develop Covid-19.

“They are therefore a priority for immunisation should an efficacious vaccine be developed,” the researchers said.

“ChAdOx1 nCoV-19 appears to be better tolerated in older adults than in younger adults and has similar immunogenicity across all age groups after a boost dose,” they added.

The results come from two trial sites in the UK where the participants were enrolled between May 30 and August 8, 2020.

None of the participants included in the report had any suspected unexpected serious adverse reactions.

Maheshi Ramasamy, a consultant and co-lead investigator at the Oxford Vaccine Group, said in a statement the results were encouraging.

“We hope that this means our vaccine will help to protect some of the most vulnerable people in society, but further research will be needed before we can be sure.”

The next step in the Phase III trial taking part in Kenya, UK, South Africa, Brazil and USA is to test if the vaccine actually prevents people getting Covid-19.

According to Kemri-Wellcome Trust, Phase III trial is partly being conducted in Kenya because a vaccine which works in one population does not necessarily work in all populations.

“Therefore it’s important to find out whether the trial vaccine works among Kenyan populations to ensure that Kenyans can benefit from the vaccine if it proves to be successful,” Kemri said.

Early results of Phase III trials should definitely be known by Christmas, the Oxford Vaccine Group’s director, Andrew Pollard, said, separately.

He said it is too early to know whether and how well the vaccine works in preventing Covid-19 disease.

Three vaccines by other manufacturers - Pfizer-BioNTech, Sputnik and Moderna - have already reported robust positive data from phase three trials, with Moderna suggesting 95 per cent effectiveness.