Oxford to run trial alternating Covid-19 vaccines

LONDON — Oxford University announced on Thursday it will launch a medical trial alternating doses of COVID-19 vaccines created by different manufacturers, the first study of its kind.

The trial will show whether different Covid doses — those created by the Astrazeneca and Pfizer/BioNTech pharmaceutical companies — can be used interchangeably to allow greater flexibility in pressured vaccine delivery schedules.

The British government's Deputy Chief Medical Officer, Jonathan Van-Tam, said the trial would offer "greater insight" into the use of vaccines against Covid.

"Given the inevitable challenges of immunising 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 immunisation programme," Van-Tam said.

"It is also even possible that by combining vaccines, the immune response could be enhanced giving even higher antibody levels that last longer," he added.

The 13-month study will compare different combinations of prime and booster doses of the Astrazeneca and Pfizer vaccines at intervals of four and 12 weeks.

Britain, the first western nation to launch its vaccination programme, has bucked the international trend by administering vaccines at an interval of 12 weeks in a bid to give a first dose of the vaccine to more individuals.

Professor Matthew Snape from Oxford University called the study "extremely exciting", adding that it would provide "information vital to the roll out of vaccines in the UK and globally". 

If the study shows positive results, Britain's independent medicines regulator would formally assess the safety and efficacy of any new vaccination regimen before it is rolled out to patients. 

Disagreements between the UK and the European Union over vaccine supplies have boiled over in recent weeks with Brussels moving to restrict vaccine exports to Northern Ireland on Thursday before the plans were abandoned in a swift U-turn.

In the following days, EU member states and the European Commission have continued to criticise the English-Swedish drugs manufacturer AstraZeneca over slow vaccine delivery and the efficacy of the jab has also been called into question. 

On Wednesday, the British government seized on a separate study that said the AstraZeneca vaccine — which was developed in partnership with Oxford University — significantly reduces virus transmission and is highly protective after a single dose.

AstraZeneca and Oxford University said on Wednesday vaccines against new developing coronavirus variants should be ready by October.