A coronavirus vaccine developed by the University of Oxford has triggered an immune response among hundreds of healthy volunteers during early-stage clinical trials and appears to be safe, according to reports.

The AZD1222 vaccine — which is being developed by AstraZeneca and scientists at the UK university – also did not cause any serious side effects, according to trial results published in The Lancet medical journal, Reuters reported.

The experimental vaccine elicited antibody and T-cell immune responses, according to the results, which showed that people who received two doses exhibited the strongest response.

“We are seeing good immune response in almost everybody,” said Dr. Adrian Hill, director of the Jenner Institute at Oxford. “What this vaccine does particularly well is trigger both arms of the immune system.”

Hill said that neutralizing antibodies — molecules that are key to blocking infection — are produced and that the vaccine also causes a reaction in the body’s T-cells, which help to fight off the virus.

The experimental vaccine caused minor side effects like fever, chills and muscle pain more often than in people who got a control meningitis vaccine.

Several countries including the US, UK, France, Germany, Italy and the Netherlands have all signed deals to receive hundreds of millions of doses of the vaccine, which has not yet been licensed.

The first deliveries are scheduled for the fall.

“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,” vaccine developer Sarah Gilbert said, according to Reuters.

“We still do not know how strong an immune response we need to provoke to effectively protect against SARS-CoV-2 infection,” she said, adding that researchers needed to learn more about the deadly bug and continue late- stage trials, which have already begun.

The researchers first began testing the vaccine in April in about 1,000 people, half of whom got the experimental shot to see what kind of immune response it generated.

They said they found that their experimental vaccine produced a dual immune response in people aged 18 to 55 that lasted at least two months after they were immunized.

Hill said that larger trials evaluating the vaccine’s effectiveness, involving about 10,000 people in the UK as well as subjects in South Africa and Brazil are still underway.

Another big trial is scheduled to start soon in the US, where about 30,000 people will be enrolled.

Hill estimated that the experts might have sufficient data by the end of the year to decide if the vaccine should be adopted for mass vaccination programs.

“There’s increasing evidence that having a T-cell response as well as antibodies could be very important in controlling COVID-19,” he said, adding that the trial tested two doses administered about four weeks apart.

The experimental vaccine uses a harmless chimpanzee cold virus, engineered so it can’t spread, to carry the coronavirus’ spike protein into the body, which should prompt an immune system response.

Oxford partnered with the drugmaker AstraZeneca, which has already committed to making 2 billion doses, Hill said.

“Even 2 billion doses may not be enough,” he said, stressing the importance of having multiple shots to combat COVID-19.

“There was a hope that if we had a vaccine quickly enough, we could put out the pandemic,” Hill said, noting the continuing surge of infections across the world. “I think it’s going to be very difficult to control this pandemic without a vaccine.”

Meanwhile, Chinese researchers also published a study on their experimental CanSino Biologics’ vaccine in the Lancet on Monday, using a similar technique as the Oxford scientists.

They reported that in their study of about 500 people, an immune response was detected in those who were immunized – but they noted that because the subjects weren’t exposed to the virus afterward, it wasn’t possible to tell if they were protected from the illness.

The Chinese vaccine is made with a human cold virus, and the study showed that people whose bodies recognized it didn’t get as much of the presumed COVID-19 benefit.

Nevertheless, Beijing already gave special approval for the military to use CanSino’s vaccine while it explores final-stage studies.

Naor Bar-Zeev and William Moss of the Johns Hopkins Bloomberg School of Public Health called both the Oxford and Chinese results “encouraging” but said in an editorial that further judgment should wait until the vaccine is tested on much bigger populations.

They also called for any effective vaccine to be distributed equitably around the world.

“Global planning is underway, but should be underpinned and informed by specific local realities,” they wrote. “Only this way can these very encouraging first early-phase randomized trial results yield the global remedy for which we all yearn.”

Last week, an initial safety trial by US biotech firm Moderna of a potential vaccine produced neutralizing antibodies in everyone who was tested.

With Post wires