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Volunteers needed for fourth dose COVID-19 vaccine booster comparison study


Public Health Wales is seeking volunteers to take part in a study looking at the use of COVID-19 vaccine that targets the Omicron variant when given as a fourth dose.  

This study, held at Wrexham Maelor Hospital, is being run by Betsi Cadwaladr University Health Board, on behalf of Public Health Wales NHS as the site, and is sponsored by University Hospital Southampton NHS Foundation Trust. 

You may be eligible to take part in the study if you: 

  • Are aged 30 years old or above 

  • Received Pfizer or Moderna as your third dose booster at least 3 months (84 days) ago 

  • Have not tested positive for COVID-19 on a PCR, lateral flow, or saliva test 

The study team will provide reimbursement up to £225 for your time, inconvenience and travel (depending on the total number of visits you attend). 

Dr Orod Osanlou, Principal Investigator for Public Health Wales and the COV-Boost study at Betsi Cadwaladr University Health Board, said: “We are very happy to be running this sub-study in Wrexham that will be giving people a fourth dose of COVID-19 vaccine which specifically targets the Omicron variant. The Omicron variant is currently the most common variant of the virus which causes COVID-19 in the UK, and is more capable of evading the immune response generated by current vaccines than previous variants. This study will help us to find out the side effect profile and immune response with this specific Omicron variant vaccine." 

Participants are required to attend a screening and vaccination visit, followed by four subsequent visits for blood tests. Participants will also be asked to keep an eDiary of any symptoms following vaccination. The total study participation time is up to 8 months. 

If you are interested in finding out more, please visit the study website where you can also complete the pre-screening questionnaire to see if you will be eligible. 

This call for volunteers follows an earlier call for 18-30 year olds to take part in a trial examining lower dose booster vaccinations, which is still seeking participants