Europe Splits With U.K. on Covid Shot-Stretching Strategy

(Bloomberg) -- The European Union’s top medicines regulator said altering the way coronavirus vaccines are given to people in a bid to stretch supplies and slow the fast-spreading pathogen raises the risk of reducing effectiveness, in a split with its U.K. counterpart.

Vaccine developers haven’t provided sufficient evidence to justify cutting the number of doses each person receives, lengthening the time between shots or mixing vaccines from different manufacturers, the European Medicines Agency said Friday in an emailed response to questions.

The watchdog outlined its position after Britain moved forward with plans allowing for second doses of some vaccines to be administered as many as 12 weeks after the first, longer than the timing determined as optimal for the shot created by Pfizer Inc. and BioNTech SE. A new surge in infections has boosted calls worldwide to experiment with dosing regimens to get more people their first shots, and provide initial protection, quickly.

Brexit has allowed the U.K. to blaze its own regulatory path, and the move on vaccines emphasizes its new independence.

Under mounting pressure, Britain has set an ambitious target of immunizing about 15 million elderly and vulnerable people by the middle of next month amid heightening spread of a variant of the virus that’s believed to be more contagious than earlier versions. London Mayor Sadiq Khan on Friday declared a “major incident” in the U.K. capital, warning the state-run National Health Service is at risk of being overwhelmed.

Steps to change the way vaccines are administered have also raised concerns. After a key U.S. official proposed cutting dosage levels for Moderna Inc.’s shot as a way to immunize more people, the U.S. Food and Drug Administration earlier this week urged that vaccines be given according to their authorizations.

Biden Policy Outlined

However, the incoming Biden administration aims to stop holding back vaccine supply, a departure from the Operation Warp Speed program’s current policy that was set to ensure second doses would be available in a timely way. Biden “believes we must accelerate distribution of the vaccine while continuing to ensure the Americans who need it most get it as soon as possible,” said TJ Ducklo, a spokesman, in an emailed statement.

Without supporting data, changes in the administration of a vaccine from what is described in the approved product information might increase the chances people could lose protection, the European watchdog said. The agency said it would review any new evidence on dosing schedules available in the future and update guidelines accordingly.

“It is obvious that time matters,” Harald Enzmann, chairman of the EMA’s drug advisory panel, said in a briefing Friday. “What we can do is say we know it works in a specific time window, and this is our approval. Beyond that is a scientific judgment, and currently I’m not aware that we have sufficiently hard data that would give us a reason to put this into the marketing authorization.”

U.K. health authorities have said they would allow for a longer gap between the first and second doses to maximize the number of vulnerable people who will get some protection in the shortest possible time. That would have the greatest impact in curbing deaths and hospitalizations, while protecting an already strained health system, officials said.

Risks, Benefits Weighed

The benefits of spacing out shots would likely outweigh concerns about the consequences, according to the British Society for Immunology.

British officials have said the data show the first vaccines to be authorized provide considerable defense after a single dose, with the second shot important over the longer term. In clearing Moderna Inc.’s shot on Friday, however, the country’s drug regulator recommended a shorter dosing timeline, with two doses given four weeks apart.

U.S. regulators have said that the effectiveness seen in late-stage trials can only be safely attained if the Pfizer shot is received at an interval of 21 days, and the U.S. company has emphasized its vaccine should be delivered to individuals within that recommended three-week period.

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