“We’re getting both sides of the immune system stimulated and that is fairly unusual for vaccines,” Adrian Hill, director of the Jenner Institute at Oxford University, told NBC News.The T cell response was noted within 14 days of receiving the vaccine. This immune response was detected for at least 56 days after getting the shot, though it’s unclear how long it will last.Fatigue and headache were the most common side effects reported by the 1,077 study participants, all adults.Asked whether a finished vaccine was likely in the next year, Hill said the research was still targeting 2020.”A vaccine later this year is not impossible, a lot of things would have to go right for that to happen and to be deployed in 2020, but we’re still targeting that.”The clinical trial did not establish whether the vaccine protects against coronavirus infection. That will be determined in the phase 3 trials, which are currently taking place in Brazil, South Africa and the United Kingdom. Trials will also be started in other parts of the world, including the United States.The vaccine is made from a weakened form of a common cold virus, called an adenovirus, that’s been genetically tweaked so that it can’t grow in humans. It’s also been modified to carry instructions to make the coronavirus’s notorious spike protein, the basic idea being that if the vaccine can instruct human cells to make this protein, the human system can learn to recognize it and better protect against infection.

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Early research found that the experimental vaccine induced antibody production in six rhesus macaques. These monkeys are considered to be good proxies for how drugs could work in people because they share a majority of their genes with humans. When the researchers exposed the vaccinated animals to the coronavirus, they did not develop pneumonia or other lung problems.

Dozens of teams across the world are working on potential coronavirus vaccines.

Moderna, a Cambridge, Massachusetts-based biotech company, published its phase 1 trial results of its vaccine last week, and announced plans to begin its final phase of human testing at the end of July. In the phase 1 trial, researchers reported that all 45 volunteers developed antibodies key to fighting the coronavirus.

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