AstraZeneca now has a 'winning formula' for its COVID-19 vaccine, CEO says

AstraZeneca's early COVID-19 trial data not only fell short of Pfizer and Moderna's expectation-beating stats, they raised a host of questions thanks to a dosing error in one group of trial patients. But with the U.K. suffering under a new viral strain and a quick vaccine approval expected, CEO Pascal Soriot says AZ has a new "winning formula."

In the company's original phase 3 trial, patients given a half dose followed by a full dose a month later were better protected than those who received two full doses. Soriot has said the company will need to conduct a new trial for U.S. authorization, but across the pond, Sky News reports a U.K. nod could come this week. 

Meanwhile, Soriot told the Sunday Times that "we think we have figured out the winning formula and how to get efficacy that, after two doses, is up there with everybody else." AstraZeneca hasn't publicly released new COVID-19 efficacy data since its initial publication in late November, and Soriot said he can't share more details "because we will publish at some point."

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In AZ's November data release, the half-dose regimen was 90% effective compared with 62% for two full doses. On average, the vaccine was 70% effective. While that's a promising number for a vaccine developed in the span of months, it came short of Pfizer and Moderna's efficacy figures of 95% and 94.5%, respectively. 

Many experts are rooting for the AstraZeneca vaccine to succeed because it's much cheaper than the mRNA shots from Pfizer and Moderna. Plus, it doesn't come with the stringent cold chain distribution requirements associated with those vaccines. AZ and its development partner, the University of Oxford, have teamed up with drugmakers around the globe to expand supply for a worldwide vaccination push.

Meanwhile, in the U.K., the government has purchased 100 million doses of the AZ vaccine. Distribution there could start next week, the Sunday Telegraph reported, but the government said the country's drug regulator must have "time to carry out its important work, and we must wait for its advice." Pfizer's vaccine is already being distributed in the U.K.

RELATED: AstraZeneca, J&J COVID-19 shots must succeed to meet U.S. vaccination goal: Slaoui

In the U.S., officials are continuing the rollout of the Pfizer and Moderna vaccines, but Operation Warp Speed head Moncef Slaoui, Ph.D., has said more vaccines will need to be successful to meet the country's immunization goal.

As of Monday, The New York Times reports that at least 1.9 million people in the U.S. have received a first dose of a coronavirus vaccine. Globally, more than 4.4 million shots have been administered, according to Bloomberg.