Following the news that interim results from the ongoing Phase I/II COV001 trial, led by Oxford University, showed AZD1222 was tolerated and generated robust immune responses against the SARS-CoV-2 virus in all evaluated participants;

Johanna Swanson, Product Manager at GlobalData, a leading data and analytics company, offers her view:

“The results of the AZD1222 vaccine are promising for showing immune response, however, more data will needed to demonstrate that the vaccine provides protection from COVID-19, along with the duration of the immunity. The vaccine could reduce disease manifestation but not reduce spread as individuals could still be contagious, for example.

“Dependent on several unknown factors, including how fast the virus mutates, the biology of the immune response, to what degree the detectable antibodies actually provide resistance to the disease, how it affects different age groups and the degree of accuracy of the antibody tests, vaccine duration could be a big hurdle. If it only lasts for a year, then it will likely require re-administration as a booster, which could affect its usefulness. Repeated administration can cause the generation of neutralizing antibodies to attack the adenovirus vector present in the vaccine and reduce the effectiveness of the vaccine, or any vaccine based on a similar vector.

“However, it is encouraging that the ten individuals that received a second dose of showed 100% neutralizing activity against SARS-CoV-2 one month after vaccination.”

“Even if AZD1222 only reduces the severity of the illness, adenovirus-vectored vaccines traditionally provide strong immune responses, which should allow them to compete with mRNA, DNA and protein subunit vaccines such as Moderna’s mRNA-1276 vaccine and Inovio’s INO-4800 DNA vaccine.”