Oxford trial to test the effectiveness of mixing vaccines for individuals

Oxford University, with the support and bankrolling of the government's vaccine task force, is looking for volunteers for a pioneering trial to establish the effectiveness of giving individuals different vaccines for their first and second doses. 

Hugely Important Trial

The proposed study has been described as "hugely important" by ministers and will recruit 820 people over the age of 50 who have not got their jabs yet. These people are to receive the first dose of either the Oxford/AstraZeneca vaccine or the Pfizer/BioNTech vaccine. At a second appointment within 12 weeks, some of these people will receive an alternative vaccine while others will get the same jab once more.

The procedure is intended to reveal whether mixing vaccines offers better, same, or reduced protection when compared to sticking to the same vaccine. 

According to the scientists monitoring the study, the information garnered would be beneficial to the UK and the whole world in general, especially considering the patchy nature of the supply of vaccines. They are also looking at the possibility of boosting protection against the more infectious COVID-19 variants by giving people two different vaccines in a row. 

Enhanced Immune Response

Matthew Snape, an associate professor in pediatrics and vaccinology at the University of Oxford, who is also the chief investigator in the trial said: "If we do show that these vaccines can be used interchangeably in the same schedule, this will greatly increase the flexibility of vaccine delivery and could provide clues as to how to increase the breadth of protection against new virus strains".

The deputy chief medical officer for England and the senior responsible officer for the study, Prof Jonathan Van-Tam, also said: "Given the inevitable challenges of immunizing large numbers of the population against Covid-19 and potential global supply constraints, there are definite advantages to having data that could support a more flexible immunization program, if needed and if approved by the medicines' regulator".