Coronavirus: AstraZeneca Oxford vaccine candidate shows promise in trials

February 3, 2021
Keith A. Reynolds

The AstraZeneca Oxford University COVID-19 coronavirus vaccine candidate is showing promise in the U.K.

According to a news release, the candidate showed 76 percent efficacy from 22 to 90 days after receiving a single dose. Efficacy rises with the inclusion of a second dose raises the efficacy to 82.4 percent with a three-month interval.

The candidate also showed a 67 percent reduction in spread of the disease, the release says.

“These new data provide an important verification of the interim data that was used by more than 25 regulators including the MHRA and EMA to grant the vaccine emergency use authorization,” Andrew Pollard, Chief Investigator of the Oxford Vaccine Trial, and co-author of the study says in the release. “‘It also supports the policy recommendation made by the Joint Committee on Vaccination and Immunisation (JCVI) for a 12-week prime-boost interval, as they look for the optimal approach to roll out, and reassures us that people are protected from 22 days after a single dose of the vaccine.”

The study suggests that the dosing interval has the greatest impact on efficacy and not the dosing level, the release says.

The researchers say in the release that that they hope to report data on the new variants of the COVID-19 coronavirus which have emerged in the U.K. and South Africa. They are confident their findings will be similar to that reported by other vaccine manufacturers.

Previously, vaccine candidates from Johnson & Johnson and Novavax have shown to be effective not only against the COVID-19 coronavirus, but also variants of the disease first observed in the U.K and South Africa.

The single-dose Johnson & Johnson candidate was shown to be 66 percent effective overall in preventing moderate to severe. COVID-19 after 28 days with the onset of protection observed as early as 14 days after vaccination. As part of the multinational Phase 3 ENSEMBLE study, the candidate showed the level of protection was 72 percent in the U.S., 66 percent in Latin America, and 57 percent in South Africa.

The Novavax candidate showed 89.3 percent efficacy in a Phase 3 clinical trial in the U.K. with more than 50 percent of study cases showing the U.K variant, and 60 percent efficacy in a Phase 2b clinical trial in South Africa. More than 90 percent of the cases in this test were the South African variant