Question to the Department of Health and Social Care:
To ask the Secretary of State for Health and Social Care, what (a) trials and (b) tests were conducted to ensure the (i) safety and (ii) efficiency of mixing and matching covid-19 vaccines and boosters from different manufacturers; and when those trials and tests were conducted.
The Government-funded, world-first studies on the safety and efficacy of interchanging different COVID-19 vaccines include the Com-COV1, Com-COV2 and Com-COV3 studies led by the University of Oxford, and the COV-Boost study led by University Hospital Southampton NHS Foundation Trust. Com-COV1 was launched in February 2021 and completed in June 2022. Com-COV2 was launched in April 2021 and is still ongoing. Com-COV3 was launched in January 2022 and is still ongoing. COV-Boost was launched in May 2021 and completed in April 2023. More information on these studies is available at the following links:
https://comcovstudy.web.ox.ac.uk/about-com-cov1
https://comcovstudy.web.ox.ac.uk/about-com-cov2
https://comcovstudy.web.ox.ac.uk/about-com-cov3
https://covboost.web.ox.ac.uk/about
All these studies have found interchanging vaccines to be safe and, in some cases, more likely to produce a stronger immune response. These findings have helped to inform the United Kingdom’s COVID-19 vaccination programme as well as vaccine policy around the world. Preliminary data from these studies was shared with the Joint Committee on Vaccination and Immunisation, Vaccine Taskforce and the Department as it became available.