A Covid-19 vaccine candidate developed by the University of Oxford and licensed to AstraZeneca has advanced into a Phase III clinical trial in the US.

The trial is designed to evaluate the safety, efficacy and immunogenicity of the AZD1222 vaccine to prevent Covid-19 in up to 30,000 adults aged 18 years and above.

Led by AstraZeneca, the study is funded by the US’ Biomedical Advanced Development Authority (BARDA) and the National Institute of Allergy and Infectious Diseases (NIAID).

The COVID-19 Prevention Network (CoVPN), support by NIAID, will be part of the trial.

AstraZeneca BioPharmaceuticals R&D executive vice-president Mene Pangalos said: “We are pleased that AZD1222 demonstrated safety and immunogenicity across all adult age groups and are proud to be collaborating with BARDA and NIAID to accelerate the development of this vaccine.

“Should clinical trials demonstrate the vaccine protects against Covid-19 disease and is approved for use, we will work hard to make it globally available in a fair and equitable manner as rapidly as possible.”

The US trial will involve healthy participants from different racial, ethnic and geographic groups, as well as those with stable underlying medical conditions, including HIV, who are at increased risk of Covid-19 infection.

Based on estimated transmission rates of the virus, sites outside the US are included, with centres in Peru and Chile set to begin enrolment soon.

Participants will be given two doses of AZD1222 or a saline control four weeks apart. Twice as many subjects will receive the vaccine candidate compared to saline control.

The study will analyse efficacy and safety in all participants, while local and systemic reactions and immune responses will be evaluated in 3,000 subjects.

Late-stage trials of the vaccine candidate are ongoing in the UK, Brazil and South Africa, with studies planned to launch in Japan and Russia. These trials, along with the US Phase III trial, will recruit up to 50,000 participants worldwide.

Results from the late-stage studies are expected to be available later this year.

Last month, AstraZeneca started dosing participants in a Phase I trial of monoclonal antibody (mAb) combination therapeutic AZD7442 to prevent and treat Covid-19.