LONDON (Reuters) – A group of British doctors wrote to the British medical director to tell him to reduce the interval between doses of the Pfizer and BioNTech vaccines to six weeks, up to 12 weeks.
Britain is prioritizing the administration of the first doses of the COVID-19 vaccine, allowing up to 12 weeks before a second dose, to give the maximum number of people some initial protection.
But Pfizer and BioNTech warned that they have no evidence that the vaccine would continue to be protective if the second dose was given more than 21 days after the first.
The British Medical Association (BMA) said in an emailed statement on Saturday that it wrote to England’s Medical Director (CMO), Chris Whitty.
BMA said it supports the administration of a second dose up to 42 days after the first dose, but that a longer interval is not in accordance with the guidelines of the World Health Organization.
Therefore, he urged the CMO to “urgently review the UK’s current position of second doses after 12 weeks”.
“The UK’s strategy is increasingly isolated from many other countries,” said the BMA.
“BMA members are also concerned that, given the unpredictability of supplies, there may be no guarantee that second doses of the Pfizer vaccine will be available in 12 weeks.”
Whitty said at a news conference on Friday that the longest interval between doses was a “public health decision” aimed at vaccinating many more people and based on the belief that the vast majority of protection comes from the first injection.
Britain is using two vaccines, one from Pfizer and the other from AstraZeneca.
AstraZeneca supported the gap between its jabs, saying that the data showed that an 8-12 week interval was an “ideal point” for effectiveness.
The Department of Health and Social Welfare said in an e-mailed statement that its priority was to protect as many people as possible as quickly as possible.
“The decision … to change the dosage intervals for the vaccine followed a complete review of the data and was in line with the recommendations of the four UK medical directors,” said a DHSC spokesman.
About 5.38 million people received the first dose of the vaccine in the UK, government data showed.
(Reporting by Sarah Young; Editing by Jason Neely)