UCLH has begun a study to see if people receiving their booster Covid-19 vaccination can be given a lower dose of vaccine.
The COV-Boost ‘Fractional Dosing’ study, led by University Hospital Southampton NHS Foundation Trust, will see if lower doses give as good an immune response in young adults as existing doses.
Using lower doses could allow existing stocks of vaccines to be given to more people, which is important while the need for vaccines is greater than the number of doses available globally. Lower doses may also be linked with fewer side effects or lower rates of already rare adverse events.
Participants will be randomly selected to receive one of the following doses:
- A single dose of Pfizer (currently used in the UK booster programme)
- One third of a single Pfizer dose (currently recommended for 5-11 years old in the UK)
- A half Moderna dose (the dosage used by the NHS as a 3rd dose booster)
- One quarter of a single Moderna dose
The NIHR-supported study is looking for volunteers who:
- are between 18 to 30 years old
- have had two doses of the Pfizer or Moderna Covid-19 vaccines, with at least 3 months (84 days) since their second dose
- have not received a booster
People who have tested positive for Covid-19 in the past, and have had their second vaccine, can also take part in the study.
Anyone interested in finding out more or taking part in the study can visit the COV-Boost website, where they can complete the study questionnaire to see if they are eligible. Participants will be reimbursed up to £225 for their time, inconvenience and travel.
The study will take place at 15 hospitals across England, Wales and Scotland, and will include a total of over 900 participants. All participants will be monitored throughout the study for any potential side effects and will have bloods taken to measure their immune responses on the day of their first visit and then two weeks, one month, three months and eight months following vaccination.
All the trial sites are working on ways of including people in research from a wide variety of backgrounds.
At UCLH the study will be led by Professor Vincenzo Libri, Director of the NIHR UCLH Clinical Research Facility (CRF). The study will be conducted at the UCLH Vaccine Research Centre, part of the NIHR UCLH CRF, and it is supported by the NIHR UCLH Biomedical Research Centre.
Professor Libri said: "This study represents an important step towards a better understanding of the optimal dosing of Covid-19 vaccines, both in terms of safety and efficacy. At UCLH we would like to thank all volunteers and research staff for their invaluable support to the trial."
The COV-Boost study published its full initial results in the Lancet in December 2021, which found several Covid-19 vaccines were safe and boosted immunity and its early findings in September 2021 informed the UK’s booster programme. Visit the COV-Boost website to take part in this study.
