A COVID-19 vaccine being developed by AstraZeneca and Oxford University is showing promise after it produced not only an immune response in volunteers but also created “killer T-cells” to combat the virus.
The data from the study on more than 1,000 people aged 18 to 55 was published in the medical journal the Lancet Monday.
The vaccine showed significant promise on both attacking the virus and producing a response from the body that would keep the novel coronavirus from gaining a foothold.
“The immune system has two ways of finding and attacking pathogens – antibody and T cell responses,” Oxford Professor Andrew Pollard said in a release.
“This vaccine is intended to induce both, so it can attack the virus when it’s circulating in the body, as well as attacking infected cells. We hope this means the immune system will remember the virus so that our vaccine will protect people for an extended period.”
T cells are a type of white blood cell that attacks cells infected with viruses.
The study showed participants who received the vaccine had produced detectable neutralizing antibodies. Scientists believe that those antibodies are an important factor for protection against the novel coronavirus.
According to Oxford researchers, 100% of participants show neutralizing antibody activity against the coronavirus in blood tests.
Oxford researchers developed the drug using adenovirus, a genetically engineered virus, to make the vaccine. The drug carries a gene for one of the proteins in SARS-CoV-2. The vaccine inserts the protein into a recipient’s cells where the cell makes that protein. In turn, the body recognizes the protein as a foreign substance and launches an attack to kill the virus.
According to the results reported in the Lancet, the vaccine “provoked a T cell response within 14 days of vaccination (white blood cells that can attack cells infected with the SARS-CoV-2 virus), and an antibody response within 28 days (antibodies are able to neutralize the virus so that it cannot infect cells when initially contracted).”
The neutralizing activity against the COVID-19 virus also seemed to last for a period of time. Ninety-one percent of participants registered the neutralizing response one month after vaccination, and 100% of participants registered the response after receiving a second dose.
The information reported Monday were results from phase 1 and 2 trials conducted in the United Kingdom.
The vaccine did cause side effects in around 60% of the participants, the article said. The side effects were deemed mild or moderate and included fever, headaches, muscle aches and injection site reactions. The side effects resolved themselves in all cases by the end of the studies, the authors said.
The vaccine, called AZD1222, is one of 23 COVID-19 vaccines in clinical trials, according to the World Health Organization.
Representatives from AstraZeneca said last month the company is working to manufacture and distribute 2 billion doses of the vaccine by the end of the year if the vaccine is ready and approved.
The news from Oxford comes a week after the biotech firm Moderna released promising data on its potential coronavirus vaccine.
Cox Media Group
