Pfizer Supports Two-Dose Covid Vaccine Schedule After UK Passage

A pharmacist administers a dose of the Pfizer-BioNTech Covid-19 vaccine to a resident of a nursing home in the borough of the Bronx in New York City on December 21.

Photographer: Eric Lee / Bloomberg

Pfizer Inc. has said the second dose of its Covid-19 vaccine should be given to individuals within the recommended 21-day timeframe, questioning a UK decision to space out the dosing schedule.

The UK’s decision not to restrict its vaccine supply aims to quickly reach as many high-risk people as possible. As part of the government plan, the second doses could be given up to 12 weeks later, longer than the three-week timeframe determined to be optimal by Pfizer’s cutting-edge studies and the four weeks suggested for the vaccine developed by Moderna Inc.

People should get vaccinated according to the recommended schedule, Pfizer said Thursday, warning that “there is no data to show that protection after the first dose is maintained after 21 days.

Information about the effectiveness of a single dose has been misinterpreted, said Peter Marks, director of the U.S. Food and Drug Administration office that oversees vaccines. Relying on one shot, he said, “is worrying.”

“If people don’t really know how protective a vaccine is,” Marks said in an email, “there’s a risk of harm because they can assume they’re fully protected when they don’t. are not and change their behavior to take unnecessary risks. “

Comments from brands come as The British Medical Association said on Thursday that the UK’s decision will force doctors to postpone the appointments of tens of thousands of elderly and vulnerable patients to receive their second dose of the vaccine. The group called the movement “Frankly unfair.”

Anthony Fauci, America’s foremost infectious disease expert, also weighed in on the UK’s decision in an interview on NBC’s Today Show Thursday. Distributing the two doses is “Under study,” he said, without specifying by whom.

“I still think that, if done correctly, you can do a single dose, reserve doses for the second dose, and continue to do the job,” Fauci said. But he added: “You can argue, and some people are, about expanding the doses and giving a single dose at all levels and hoping that you get the second dose in time to give it to people. people.

In its statement, Pfizer said monitoring was needed on all alternative vaccination schedules and that authorities should work to ensure that each recipient receives the maximum protection possible.

“Data from the phase 3 study demonstrated that although partial protection against the vaccine appears to begin as early as 12 days after the first dose, two doses of the vaccine are required to provide maximum protection against the disease, vaccine efficacy. by 95%, ”Pfizer said in its statement.

An FDA document containing frequently asked questions about Pfizer and its partners BioNTech SE’s vaccine notes that the agency’s assessment of the vaccine’s safety and efficacy was based on data from patients who received two injections three weeks apart.

(Adds the statement by Peter Marks of the FDA in the fourth and fifth paragraphs.)