A DORSET-run, UK-wide trial found six Covid-19 vaccines could be safely as a booster and would boost immunity for those who have had two doses of AstraZeneca or Pfizer.

The Cov-Boost trial, which recruited volunteers at the Dorset Research Hub based at University Hospitals Dorset, was key to shaping the UK booster programme and gave vital evidence for global vaccination efforts.

The study, led by University Hospital Southampton, has had its latest results published in The Lancet.

Cov-Boost looked at the safety, immune responses and side-effects of seven vaccines when used as a third, booster jab. Almost 150 volunteers joined the study across Dorset.

The seven vaccines trialled were: Oxford-AstraZeneca, Pfizer-BioNTech, Moderna, Novavax, Valneva, Janssen and CureVac.

Of these, only AstraZeneca, Pfizer-BioNTech, Janssen and Moderna are currently licensed for use in the UK.

All seven were found to be safe to use as a third dose, however all but Valneva were found to be safe after two doses of AstraZeneca or Pfizer.

Professor Saul Faust, trial lead and director of the NIHR Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, said: “Our side effect data shows all seven vaccines are safe to use as a third dose, with acceptable levels of ‘reactogenicity’ – inflammatory side effects like injection site pain, muscle soreness, fatigue.

“All seven boosted levels of spike protein antibodies significantly after two doses of AstraZeneca. However only six also did so after two doses of Pfizer-BioNTech (AstraZeneca, Pfizer-BioNTech, Moderna, Novavax, Janssen and CureVac). There were also large variations in response with different boosters.

“It’s really encouraging that a wide range of vaccines, using different technologies, show benefits as a booster dose to either of these vaccines. That gives confidence and flexibility in developing booster programmes here and globally, with other factors like supply chain and logistics also in play.”

Dr Patrick Moore, a Dorset GP and local investigator for the study, said: “I would like to thank our trial participants who continue to generously give their time to support this important research. Their contributions have significantly informed the UK booster programme.

“I am proud that the Dorset Research Hub at University Hospitals Dorset continues to play such an important role in the fight against Covid-19.

“I hope the results of this trial, particularly the safety data, helps to reassure those who are now being called for their booster vaccination.”