It is “very risky” to delay the second dose of Covid-19 vaccines because the efficacy data were based on a specific dosing schedule, a former FDA director told CNBC on Thursday.
His comments came after the UK decided to administer the second coronavirus vaccine 12 weeks after the first dose, in addition to those recommended by the vaccine manufacturers. It appears that Germany is considering a similar move, while Denmark has approved a six-week dose gap.
Vaccines approved for use in the UK require both doses.
The American pharmaceutical company Pfizer and the German biotechnology company BioNTech recommended that the second dose of vaccine be administered 21 days after the first. British-Swedish pharmaceutical company AstraZeneca said the vaccine he developed with Oxford requires two doses to be given one month apart. The United Kingdom initially said it would abide by that program.
It is a very risky business, because if it fails, you are in a worse state.
Norman Baylor
Former director of the FDA
Any decision to change dosing schedules should be based on data, said Norman Baylor, former director of the US Food and Drug Administration’s vaccine research and review office.
“It is very risky to try to expand [the gap between two doses] or give a single dose in the absence of data, “he told CNBC on Thursday for” Street Signs Asia. “
“I understand some of the reasoning for doing this, but again, it’s not really based on data,” said Baylor, who is also president and CEO of Biologics Consulting. “It’s a very risky business, because if it fails, you’re in a worse state.”
The UK’s controversial decision came as the country continues to struggle with a new, rapidly spreading coronavirus strain, although there is no evidence that it is more severe or deadly. About 62,322 cases were reported on Wednesday and more than 2.8 million people have tested positive for the virus so far, according to government data.
A nurse is preparing the Oxford-AstraZeneca vaccine at Pontcae Medical Practice on January 4, 2021 in Merthyr Tydfil, Wales.
Matthew Horwood | Getty Images News | Getty Images
Delaying the second dose of the vaccine means more people can get their first dose, but Baylor said it would be ideal to follow the dosing regimen in vaccine efficacy studies.
“If you don’t have the data, you risk it,” he said. “This is the key point, the risk you take.”