By Jenny Strasburg and Drew Hinshaw
LONDON -- The U.K. asked its medicines regulator to review AstraZeneca PLC's Covid-19 vaccine for emergency-use approval, while Europe's equivalent of the FDA said it could be more flexible in how it reviews a handful of promising candidates.
The two moves accelerate a regulatory race on both sides of the Atlantic, triggered by the recent publication of positive clinical data for three different vaccine candidates. Two shots -- one from Pfizer Inc. and Germany's BioNTech SE, and another from Moderna Inc. -- showed to be more than 90% effective at preventing symptomatic Covid-19 in large-scale human trials.
On Monday, AstraZeneca said the vaccine it has developed with the University of Oxford showed to be as much as 90% effective, but only among a small subset of subjects who received a lower first dose of the two-shot regimen. In the other group of trial subjects given two full doses, the vaccine showed 62% efficacy.
While that overall reading falls well short of the other two vaccines, AstraZeneca said the results showed its shot was still effective enough against the virus to provide protection and that the company hoped for regulatory approval in Europe in coming weeks, soon enough to potentially have the vaccine in use by year-end.
The U.K. on Friday formally requested that the country's Medicines and Healthcare products Regulatory Agency review the AstraZeneca vaccine for emergency use in the country. Such authorization depends on full safety and efficacy data that the vaccine partners have yet to submit, U.K. officials said. The MHRA hasn't provided a timeline for its review process.
Still, the British government said in a statement its request "would mean potentially faster access to the vaccine for U.K. patients," dependent on approval.
That sets up the U.S. and the U.K. as the two most likely markets to get at least one of the three vaccines first, should regulators ultimately approve any of them. Pfizer has already submitted an approval application to both the Food and Drug Administration in the U.S. and the British regulator.
European Union regulators, meanwhile, say they might need until next year to assess the candidates.
The U.K. is in a transition period, through Dec. 31, in its process to exit from the EU. That means medicine approvals are still in most cases handled by the European Medicines Agency, that bloc's top medicines regulator. But the U.K. retains the power to authorize medicines for emergency use, and the government has said it would do so if the MHRA signs off on a vaccine before the end of the year.
The EMA has yet to receive an application from any of the vaccine makers, officials there said, though it expects that in coming days. It said it was willing to be more flexible in speeding up its vaccine approval procedures. In a notice published Friday, it invited drugmakers to contact the agency to discuss strategies to quicken the review process.
The "EMA is ready to apply further flexibility, where it is established that shortening of any other procedural step could have an important public-health impact in dealing with the Covid-19 pandemic," the notice said.
An authorization of one of the front-runner candidates could come "towards the end of this year at the earliest," a spokeswoman at the agency said.
The FDA hasn't detailed an approval timeline, but executives and officials expect it to be in a position to grant emergency-use authorization for the Pfizer shot by the end of the year.
Moderna is expected to submit its vaccine for FDA review soon.
U.S. clinical trials of AstraZeneca's shot were paused earlier this year after a trial subject in Britain fell ill. Trials were resumed after the FDA didn't find the vaccine was responsible for that and another illness, though the agency couldn't rule out a link either, a person familiar with the matter said at the time.
That has set back the timeline for the U.S. trial, for which AstraZeneca is still recruiting volunteers, as well as any potential FDA review of the AstraZeneca vaccine.
The British request for regulatory review follows disclosure this week from AstraZeneca about its so-called Phase 3 trials that some analysts and health officials criticized as muddled and confusing.
AstraZeneca didn't immediately disclose that the dosing difference was the result of an early manufacturing mistake. The subset that received the lower, more effective dosing included only people under 55 years old -- a factor researchers said could have contributed to the higher effectiveness.
AstraZeneca and Oxford said a peer-reviewed version of Monday's results, with more data, will be published in the next week or so. AstraZeneca executives also said they are planning a new study of the half-dose regimen that would include people over 55.
AstraZeneca has also said it plans to discuss with the FDA the possibility of altering its large-scale trials in the U.S. to add a new segment of participants who would receive the half-dose-full-dose combination that proved 90% effective in the subset of trials reported this week.
Mene Pangalos, AstraZeneca's executive vice president for biopharmaceuticals research and development, said in an interview this week that a new study looking at over-55 subjects on the half-dose regimen would take some time.
"We've got to set up the study, we've got to start recruiting," he said. He said the 62% efficacy shown in the larger group of trial volunteers was enough to move forward with seeking authorization.
"We just look at the worst-case scenario, which is the vaccine is 62% effective -- it's still an effective vaccine," he said.
Write to Jenny Strasburg at email@example.com and Drew Hinshaw at firstname.lastname@example.org
(END) Dow Jones Newswires