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Paxlovid is now approved to treat mild to moderate Covid-19.
CNN  — 

The US Food and Drug Administration on Thursday fully approved the antiviral medication Paxlovid to treat mild to moderate Covid-19 in adults at risk of severe infections.

Paxlovid had been available for adults and teens in the United States under an emergency use authorization, or EUA, which strictly limited how the medication could be prescribed.

The FDA’s standards for full approval are stricter than those for an EUA.

“Today’s approval demonstrates that Paxlovid has met the agency’s rigorous standards for safety and effectiveness, and that it remains an important treatment option for people at high risk for progression to severe COVID-19, including those with prior immunity,” said Dr. Patrizia Cavazzoni, director of the FDA’s Center for Drug Evaluation and Research, in a news release.

Full approval will give doctors more leeway in how they use the drug. For example, they may choose to prescribe a longer course if a person shows signs that their infection may coming back, a phenomenon called rebound.

The FDA says Paxlovid should be used to treat only Covid-19. It should not be used as pre-exposure or post-exposure prevention of the infection.

Paxlovid is a combination of two medications – nirmatrelvir and ritonavir – which are taken together as pills for five days within the first five days of a person’s Covid-19 symptoms.

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In the clinical trials that led to the medication’s approval, Paxlovid reduced the risk of hospitalization or death by 86% compared with a placebo in people at risk for severe disease because of their age or an underlying health condition.

The FDA says that Paxlovid is the fourth drug and first pill to be approved for the treatment of Covid-19.

It is difficult for some people to take because it has interactions with many other types of medications. For that reason, it will come with a black box warning about its potential to interfere with other drugs.

Today’s approval covers only treatment for adults, but the FDA says the drug will still be available for adolescents ages 12 to 18 under emergency use authorization.