An experimental coronavirus vaccine with more than $1 billion in U.S. government funding is safe and creates a strong immune response, according to a study published in a major medical journal Monday.
The vaccine developed by the University of Oxford and AstraZeneca produced a promising immune response that lasted for nearly two months in an early trial involving more than one thousand healthy adults, researchers reported in The Lancet.
The response was even stronger in 10 participants who received a second dose, the scientists said.
AstraZeneca in May struck a $1.2 billion deal to provide the U.S. with 300 million initial doses of the shot this fall. The company also promised the U.K. 100 million initial doses.
Background: British researchers began the first human trials of the vaccine in April.
The Oxford study combines the initial Phase I safety trials with Phase II trials that examine both safety and the strength of any immune response. The results show that the vaccine induced not only a strong antibody response but also the production of immune cells called T cells. Scientists say both can be vital to a durable vaccine.
“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 Sarah Gilbert, one of Oxford’s lead researchers on the study, in a statement. “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.”
The Oxford and AstraZeneca vaccine is based on a weakened version of the common cold that contains genetic components of the coronavirus.
What’s next: Researchers have already moved into combined Phase II and III trials in several countries. Phase III trials are normally the final step to determine if a vaccine is effective.
Oxford researchers have also said they are open to intentionally infecting people with the virus in future trials to see if the vaccine definitely works, an approach known as human challenge studies.
“If our vaccine is effective, it is a promising option as these types of vaccine can be manufactured at large scale,” Gilbert said.