AstraZeneca and the University of Oxford recently resumed their vaccine trials after the death of a volunteer was confirmed to occur after taking part in the meningitis control group and did not receive a dosage of the vaccine candidate. The company has recently shared that AZD1222/ChAdOx1 nCoV-19 vaccine shows similar immunogenicity responses in both young and old adults.
CEO Pascal Soriot ensures that their trials are continuously evaluated by independent regulators to protect the volunteers and for the vaccine candidate to be thoroughly assessed for safety measures before public use.
An AstraZeneca spokesperson said that reactogenicity was lower in older adults, who are in the high-risk group of infection, and typically experience severe coronavirus symptoms. Thus far, the trials have resulted in evidence of the vaccine's safety and immunogenicity.
Antibody and T-Cell Production
Their July study published in The Lancet from the first two phases of clinical trials has shown that older people had a positive immune response to the vaccine. Results showed that AZD1222 triggers antibodies and T-cells in the immune system.
The safety of over 1,000 volunteers was assessed for about a month after vaccination. Some reactions to the initial trials included pain, muscle ache, headache, and fatigue, which were treated with prophylactic paracetamol. There were no serious adverse events during the first two phases of clinical trials.
The vaccine candidate is expected to be one of the first to receive regulatory approval despite the temporary pause in trials. Experts anticipate that the Pfizer and BioNTech vaccine candidates will also receive regulatory approval soon.
A new study with updates results of the current clinical trials is soon to be published as well. UK Health Secretary Matt Hancock said that he expects the vaccine to be available by early next year. Although he did not rule out the possibility of the vaccine being available before 2021, it "is not [his] central expectation." What's important is that the clinical trials are progressing well, he said.
The published study said that the vaccine could protect for at least 56 days. Soriot said that protection could last for up to a year.
Professor Jonathan Ball from the University of Nottingham said that data showing how good immunity is generated among volunteers over the age of 55 is a promising sign. He is still anticipating results if the vaccine candidate can protect against severe cases of coronavirus.
Read Also: Should Wearing Face Masks be Mandated in the United States?
Trials Still On Hold in the U.S.
In the meantime, trials in the United States are still on hold but have resumed in the UK, Brazil, South Africa, and India. American participants are still waiting for trials to continue so that they can receive their second dose or the booster shot.
Participants were supposed to receive a second dose after 28 days if trials were not paused. Kathryn Edwards from the Vanderbilt Vaccine Research Program assured participants not to worry about waiting for a second dose since "spacing vaccines out with longer intervals between them is usually not associated with a decline in the immune response."
Read Also: Astrazeneca's COVID-19 Vaccine Trials to Continue Even After a Volunteer Dies
Check out more news and information on Vaccines on Science Times.
