Moderna CEO: Vaccine Will Likely Work for 'a Couple of Years'

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The Moderna vaccine ― one of two vaccines now being distributed in the United States ― will "potentially" provide protection against COVID-19 for several years, the biotech company's CEO said, according to Reuters.

But Stephane Bancel said the Massachusetts-based Moderna will have to conduct more research to be definitive about how long the vaccine will work. Because coronavirus vaccines are new, health experts aren't sure how long they'll be effective.

"The nightmare scenario that was described in the media in the spring with a vaccine only working a month or two is, I think, out of the window," Bancel said at an event organized by the Franco-German financial services group Oddo BHF.

"The antibody decay generated by the vaccine in humans goes down very slowly (...) We believe there will be protection potentially for a couple of years."

Bancel went on to predict Moderna would soon prove its vaccine would work against coronavirus variants found in the United Kingdom and other nations, Reuters said.

The U.S. government approved the Moderna vaccine for distribution in the United States on Dec. 17, one week after approving the Pfizer/BioNTech vaccine. Both are now being administered in the United States and the Moderna vaccine was recently approved by the European Commission.

Moderna and Pfizer both use two shots of messenger RNA to create an immune response against the coronavirus. The shots are given about two weeks apart.

Moderna said its vaccine had proven to be 94.1% effective, and 100% effective in severe cases of COVID-19. Pfizer says its vaccine has a similar efficacy, 95%.

The U.S. Department of Health and Human Services has agreed to purchase 200 million doses of Moderna's vaccine, and could purchase more.

Despite increasing coronavirus case counts and deaths, distribution of the coronavirus vaccine has lagged in the United States. The CDC says 17.2 million doses have been distributed to the states as of Dec. 6, but only 5.3 million doses have been administered.

Vaccines being produced by AstraZeneca and Johnson & Johnson are still in clinical trials.