- Pharmaceutical company AstraZeneca said a potential Covid-19 vaccine generated a 'robust' immune response against the SARS-CoV-2 virus in all participants, in a trial being led by Oxford University.

The trial involving 1,077 healthy adult participants confirmed a single dose of the vaccine resulted in a four-fold increase in antibodies to the virus's spike protein in 95% of participants one month after injection.

SARS-CoV-2 is the virus that causes the disease Covid-19.

T-cell response was induced in all participants, peaking by day 14, and maintained two months after injection.

Neutralising activity against SARS-CoV-2 was seen in 91% of participants one month after vaccination and in all of the 10 participants who received a second dose, one month apart.

The levels of neutralising antibodies seen in participants receiving either one or two doses were in a similar range to those seen in convalescent Covid-19 patients.

Oxford University chief investigator Andrew Pollard said the trial data showed the vaccine did not lead to any unexpected reactions and had a similar safety profile to previous vaccines of its type.

'The immune responses observed following vaccination are in line with what we expect will be associated with protection against the SARS-CoV-2 virus, although we must continue with our rigorous clinical trial programme to confirm this,' Pollard said.

'We saw the strongest immune response in participants who received two doses of the vaccine, indicating that this might be a good strategy for vaccination.'

AstraZeneca said late-stage trials were currently underway in the UK, Brazil and South Africa and due to start in the US.

Trials would determine how well the vaccine would protect from the Covid-19 disease and measure safety and immune responses in different age ranges and at various doses.

The company said that, so far, commitments to supply more than 2bn doses of the vaccine had been agreed with the UK, US, Europe's Inclusive Vaccines Alliance, the Coalition for Epidemic Preparedness, Gavi the Vaccine Alliance and Serum Institute of India.

AstraZeneca said news of the positive trial results were not expected to impact its financial guidance for 2020, as expenses to progress the vaccine were anticipated to be offset by funding by governments and international organisations.

At 2:58pm: [LON:AZN] Astrazeneca PLC share price was +129.5p at 9316.5p

Story provided by