Video report by Tim Scott.
It is hoped the Oxford/AstraZeneca variant vaccine will protect against new strains, as well as ''boosting'' the immune systems of those eligible to have it.
The study is being delivered by Manchester University Foundation Trust's Research and Innovation Vaccine Team, with around 2,800 volunteers taking part from Greater Manchester and Cheshire.
The trust is one of 14 sites across the country to be delivering the Oxford/AstraZeneca vaccine booster study.
It is being administered as a single-dose booster to participants who are already fully vaccinated with two doses of an approved coronavirus vaccine. This booster dose must be at least three months after their last injection.
The study is also recruiting people who have never received a COVID-19 vaccine and these participants will receive two doses of the trial variant vaccine.
Professor Andrew Ustianowski is the Principal Investigator for the study at MFT.
Professor Ustianowski said: "Throughout the pandemic the UK has demonstrated its expertise in clinical vaccine research, consistently supported by the fantastic efforts of our study participants in Greater Manchester and across the country.
"The latest booster study from Oxford/AstraZeneca is just one of the latest, world-leading steps in our battle to tackle the virus and one of the variants of concern.
"We are calling on the general public once again to work alongside researchers to help recruit to this study and help gather the data we need on the new vaccine. We are extremely grateful to Sarah and all study participants."
The study is recruiting participants until August, with initial data from the trial expected later this year.
Anyone in Greater Manchester aged 18 and over and interested in taking part in research into coronavirus, or studies for various other health conditions, can register their interest by signing up to the local NHS initiative Research for the Future.
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