Researchers at Oxford University have released promising test results for a COVID-19 vaccine, which uses a novel technology based on a cold virus found in chimps, and said the drug could be in use by the end of the year.
A team at Oxford’s Jenner Institute has been working on the vaccine since January and the group has already signed a deal with pharmaceutical giant AstraZeneca PLC to make two billion doses within 12 months. On Monday, the scientists released results from the first phase of tests involving 1,077 volunteers in Britain.
“The early stage trial finds that the vaccine is safe, causes few side effects, and induces strong immune responses,” said a report on the findings published in The Lancet medical journal.
The results showed that the vaccine stimulated two key parts of the body’s immune system – antibodies and T-cells. Antibodies try to neutralize viruses when they first enter the body while T-cells destroy any cells that have already been infected by the virus. An ideal vaccine needs to activate both in order to provide long-lasting immunity.
“We’re encouraged by what we’re seeing and these are at the high end of what our expectations might have been say six months ago,” said Adrian Hill, the director of the institute. “It’s possible there will be a vaccine being used by the end of the year.”
He added that the vaccine is undergoing further tests on more than 40,000 people in Britain, the U.S., South Africa and Brazil. Results from those tests are expected this fall and if successful, the vaccine could be approved for limited use by December.
Many other scientists welcomed the Oxford results but also cautioned against overoptimism. “Developing new vaccines is a highly complicated process and success is by no means assured,” said Doug Brown, chief executive of the British Society for Immunology.
“Although the results of this trial are an important step forward, they are not the end of the story,” he said. “The researchers still have many more stages to go through before we can confirm that this vaccine is safe and effective for widespread use against [COVID-19].”
British Prime Minister Boris Johnson also applauded the Oxford group on Monday and struck a note of warning. “It may be that the vaccine is going to come riding over the hill like the cavalry. But we just can’t count on it right now,” he said.
There are more than 100 vaccine projects around the world and some in China and the U.S. have also shown early promise. Several countries have begun to hedge their bets and place orders with more than one vaccine developer.
On Monday, the British government said it had ordered 90 million doses of potential vaccines from companies in Germany and France. That was in addition to the 100 million doses of the Oxford drug Britain plans to buy from AstraZeneca. The U.S. government has secured orders for millions doses of the Oxford drug as well as one being developed by Boston-based Moderna Inc., while Canada is spending $192-million on producing a Canadian-made vaccine.
In the Oxford vaccine effort, a cold virus found in chimpanzees is genetically altered to make it harmless to humans and then engineered to produce the same spike-like proteins that the COVID-19 virus uses to infect humans.
Once injected as a vaccine, it primes the body’s immune system to recognize and attack COVID-19. The central mechanism – known as ChAdOx – has already served as a platform for vaccines for Ebola and other coronavirus diseases such as Middle East respiratory syndrome.
While the early testing has gone well, there remain plenty of unanswered questions. The researchers have yet to see how the vaccine works on older adults and it’s not clear whether one or two doses will be needed. The early testing also found no adverse side effects, according to The Lancet, but many volunteers reported some fatigue and headaches, which were managed with paracetamol.
“There’s still a long way to go,” said Sarah Gilbert, one of the Oxford researchers. “The difficulty that we have and that all vaccine developers have in trying to make a vaccine against this particular virus is that we don’t know how strong that immune response needs to be.
“So we can’t say just by looking at the immune responses whether this is going to protect people or not. The only way we are going to find out is by doing the large phase trial and waiting for people to be infected as part of that trial before we know if the vaccine can work.”
Dr. Hill said the world will need more than one vaccine and he called on researchers to work together. “We would really like to see different vaccines being tested in the same lab by the same people, so the world has a really direct comparison of the performance of different vaccines,” he said. “We do want the best vaccine.”
AstraZeneca has promised to make the Oxford vaccine available at cost during the pandemic and it has been working with manufacturers in several countries.
Monday’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,” said Mene Pangalos, AstraZeneca’s head of biopharmaceuticals research and development.
The company’s shareholders have already reaped some benefits from the vaccine program; AstraZeneca’s share price has soared 46 per cent this year on the London Stock Exchange.
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