How the U.K. Approved Pfizer’s COVID-19 Vaccine Faster Than the U.S. and Europe

The U.K. became the first western country to authorize the use of a COVID-19 vaccine on Dec. 1, when its medicines regulator gave the greenlight to the vaccine produced by Pfizer and BioNTech.

The U.K.’s Medicines and Healthcare products Regulatory Agency (MHRA) gave the authorization at record speed, just three weeks after Pfizer published the first data from the final stage of its clinical trial. Later results showed the vaccine to be 95% effective in preventing illness from COVID-19.

The announcement raises expectations for the impending decisions by regulators in the U.S. and the E.U., who are still poring over data from the vaccine’s trials. China and Russia approved vaccines for use in some groups in June and August respectively, without waiting for the results of large-scale efficacy trials.

The speed of the U.K.’s emergency authorization—at a time when the British government is aggressively seeking to boost its image after a poor handling of the pandemic—has raised eyebrows among European politicians and health experts.

But British regulators say their rapid approval of the vaccine did not cut corners. “We have carried out a rigorous scientific assessment of all the available evidence of quality, safety and effectiveness,” MHRA Chief Executive, Dr. June Raine, said in a statement. “The public’s safety has always been at the forefront of our minds—safety is our watchword.”

Here’s how the U.K. fast-tracked its vaccine approval—and what it means for the rest of the world.

How was the vaccine approved so quickly in the U.K.?

In a bid to speed up its approval of any effective COVID-19 vaccines, Scientists from the MHRA began examining trial data in October, the agency said, in a process called a “rolling review”—where packages of data from a still ongoing trial are made available as soon as they’re ready, rather than in one release at the end of the trial.

U.K. health minister Matt Hancock—and other Conservative Party politicians—claimed on Dec. 2 that the MHRA’s rapid approval of the vaccine was made possible by the U.K.’s departure from the E.U., which is due to be completed at the end of a transition period on Dec. 31.

But the MHRA has pointed to an existing provision in E.U. law that allows member states’ regulators to issue temporary approval of products for use in their own countries during public health emergencies. In October, the British government changed legislation to expand the scope of what the U.K. can do with vaccines not yet licensed by the E.U., including allowing more people to administer them, and granting the companies that produce them immunity from legal liability in some civil cases concerning the vaccine.

The U.K. has pre-ordered 40 million doses of the vaccine—enough to vaccinate just under a third of the population with the two doses required. British officials said the National Health Service will begin to roll out the vaccine early next week. Healthcare workers and nursing home residents will be the first to receive the vaccine.

Government ministers have cast the approval as a success for U.K. leadership in the international pandemic response, after the country has recorded the world’s fifth-highest death toll, with almost 60,000 having died after testing positive for COVID-19 so far. “In years to come, we will remember this moment as the day the UK led humanity’s charge against this disease,” Business secretary Alok Sharma wrote on Twitter.

How have Europe and the U.S. responded to the U.K.’s approval?

After the U.K.’s announcement, Europe’s regulator––the European Medicines Agency (EMA)––pointed out that it is moving toward a longer-term authorization that requires more checks and evidence to be submitted than the temporary approval issued by the MHRA. In an emailed statement, the EMA said it considers the “extensive data” and “robust framework” required for so-called market authorization to be “essential elements to ensure a high level of protection to citizens during the course of a mass vaccination campaign.”

With its temporary approval mechanism, the MHRA will need to approve each batch of the vaccine and technically approval could be terminated at any time, according to the EMA. Market authorization by the EMA lasts for one year before renewal.

Guido Rasi, who recently finished his term as head of the EMA, told an Italian radio station that the U.K.’s emergency approval of the vaccine was a “substantially political step that is not without risks”. “If you evaluate only the partial data as they are doing they also take a minimum of risk,” he said. “Personally I would have expected a robust review of all available data, which the British government has not done.”

European politicians have also criticized the U.K.’s decision, which could create pressure for the rest of the world to act fast. “I consider this decision to be problematic and recommend that EU Member States do not repeat the process in the same way,” said Peter Liese, a German member of the European parliament and health policy spokesperson for the center-right bloc in the legislature. “A few weeks of thorough examination by the European Medicines Agency is better than a hasty emergency marketing authorisation of a vaccine.”

In the U.S., the U.K.’s approval of a vaccine developed by an American company may add to political pressure from the Trump Administration on regulators to speed up their emergency use authorization processes. White House chief of staff Mark Meadows called Stephen Hahn, head of the Food and Drug Administration in for a meeting on Dec. 1 to discuss vaccine approval timelines. Hahn told ABC he would resist pressure to speed up the process. He pointed out that it “would typically take between three and four months, maybe even longer” for the FDA to review all the data and grant approval after a trial on the scale of Pfizer and BioNTech’s. “No one at FDA is sitting on his or her hands. Everyone is working really hard to look at these applications and get this done, But we absolutely have to do this the right way,” he said.

When will the U.S. and Europe approve the vaccine?

The U.S. FDA will hold a meeting of its advisory panel on Dec. 10 and is expected to announce shortly after if it will authorize the vaccine. In late November Pfizer CEO Albert Bourla told TIME that the company will be ready to start distributing the vaccine “within hours” of its authorization. The FDA has warned that it could take days or a few weeks after authorization for doses of the vaccine to begin reaching its first recipients as the regulator deals with bureaucratic and logistical hurdles.

The EMA has been conducting a rolling review process of the vaccine since early October in order to speed up their own assessment of the vaccine. On Dec. 1 the agency announced it had received an application for marketing authorization from Pfizer and BioNTech. The EMA will announce whether or not it is granting that authorization after a meeting of its scientific committee for human medicines, which will take place by Dec. 29.