A preliminary study investigating the safety and effectiveness of a vaccine against COVID-19 has found the vaccine to be “safe” and that it triggered a “significant” immune response in human volunteers.
The study, which was published in The Lancet on Monday (20 July), offers hope that the vaccine could pave the way for a treatment for COVID-19 and curb the spread of the virus.
The vaccine, called ‘ChAdOx1 nCoV-19’, has been created at unprecedented speed by the University of Oxford in partnership with British pharmaceutical giant AstraZeneca.
It has been developed using a genetically engineered virus that causes the common cold in chimpanzees.
Leading authorities around the world, including the United Nations, have repeatedly stressed that finding a vaccine is the only way for a return to normal life.
The study is the first randomised controlled human trial for evaluation of this kind of COVID-19 vaccine.
“Evidence from this phase 2 study indicates the candidate Ad5-vectored COVID-19 vaccine has a good safety profile, with only mild, transient adverse events related to vaccination and no serious adverse events,” the study reads.
Crucially, the study found that the vaccine provoked a T-cell response within 14 days of vaccination, and an antibody response within 28 days.
These preliminary results provide a strong basis for moving testing into phase 3 trials, where the vaccine will be tested on much larger populations of participants to assess its efficacy and safety.
In a statement, Professor Andrew Pollard, chief investigator of the Oxford vaccine trial, called this a “huge breakthrough,” although he cautioned that more work must be done to properly assess the vaccine.
“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 added.
‘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,” added 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”, he said.
‘Step in the right direction’
UK Prime Minister Boris Johnson took to twitter to welcome the news, saying “this is very positive news. A huge well done to our brilliant, world-leading scientists and researchers at @UniofOxford”.
He added that “there are no guarantees, we’re not there yet and further trials will be necessary – but this is an important step in the right direction.”
Despite still being in the early stages of testing, the BBC reports that the UK has already ordered 100 million doses of the vaccine.
In order to properly evaluate the efficacy of the vaccine, more than 10,000 people are now enrolled in the next stage of the trials, which will also be expanded to other countries, including the US, South Africa and Brazil.
Given that the initial volunteers have only been followed up for eight weeks so far after immunisation, questions remain as to how long the immune response lasts.
The vaccine must now also be tested in older adults, especially given that flu vaccinations are not as effective in older people, whose immune systems function less well than younger people’s.
[Edited by Benjamin Fox]