A coronavirus vaccine created by the University of Oxford appears safe and induces a strong immune response within the body, scientists announced on Monday after the first phase of human trials.
Doses of the vaccine were given to 1,077 healthy adults aged between 18 and 55 in five United Kingdom hospitals in April and May as part of the phase one clinical trial and results, published in the Lancet medical journal.
The results show they induced strong antibody and T-cell immune responses for up to 56 days after they were given.
T-cells are crucial for maintaining protection against the virus for years.
The findings are seen as promising, but experts feel it is too soon to know if this is enough to offer protection as larger trials get underway.
"There is still much work to be done before we can confirm if our vaccine will help manage the COVID-19 pandemic, but these early results hold promise," said Professor Sarah Gilbert, co-author of the study.
"As well as continuing to test our vaccine in phase 3 trials, we need to learn more about the virus -- for example, we still do not know how strong an immune response we need to provoke to effectively protect against SARS-CoV-2 infection.
"If our vaccine is effective, it is a promising option as these types of vaccine can be manufactured at large scale," she said.
Scientists behind the trials found the response could be even greater after a second dose.
"The Phase I/II data for our coronavirus vaccine shows that the vaccine did not lead to any unexpected reactions and had a similar safety profile to previous vaccines of this type.
"The immune responses observed following vaccination are in line with what previous animal studies have shown are associated with protection against the SARS-CoV-2 virus, although we must continue with our rigorous clinical trial programme to confirm this in humans," said Professor Andrew Pollard, Chief investigator of the Oxford Vaccine Trial at Oxford University and co-author of the study.
"We saw the strongest immune response in the 10 participants who received two doses of the vaccine, indicating that this might be a good strategy for vaccination," he said.
The project has been bolstered by 84 million pounds of government funding to help accelerate the vaccine's development.
UK Business Secretary Alok Sharma said: "Today's results are extremely encouraging, taking us one step closer to finding a successful vaccine to protect millions in the UK and across the world.
"Backed by 84 million pounds government investment for the vaccine's development and manufacture, the agility and speed with which the University of Oxford have been working is outstanding. I am very proud of what they have achieved so far."
The University of Oxford is working with the UK-based global biopharmaceutical company AstraZeneca for the further development, large-scale manufacture and potential distribution of the COVID-19 vaccine, with plans for clinical development and production of the Oxford vaccine progressing globally.
"We are encouraged by the Phase I/II interim data showing AZD1222 was capable of generating a rapid antibody and T-cell response against SARS-CoV-2," said Mene Pangalos, Executive Vice President of BioPharmaceuticals Research and Development at AstraZeneca.
"While there is more work to be done, today's data increases our confidence that the vaccine will work and allows us to continue our plans to manufacture the vaccine at scale for broad and equitable access around the world," Pangalos said.
Kate Bingham, Chair of the UK's Vaccine Taskforce added: "The UK is fortunate to have such outstanding academic innovators working alongside the highly experienced global team at AstraZeneca.
"This partnership is working at exceptional speed to demonstrate the safety and clinical effectiveness of the chadox vaccine in protecting people against Covid-19 infection."
While the results declared on Monday are from phase one of the trials, phase two testing is already underway in the UK and phase three testing on volunteers in Brazil is also taking place.
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