New antiviral drug from Merck could help reduce COVID hospitalizations and deaths

Oct 1, 2021
Originally published on October 1, 2021 4:09 pm
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A study of an antiviral drug for COVID-19 has been halted, and that is actually good news. The study was halted because the medication is showing promise. It's made by the drug company Merck in partnership with Ridgeback Biotherapeutics. NPR science correspondent Joe Palca joins us to talk about these results and what they mean for the pandemic.

Hi, Joe.


SHAPIRO: Tell us what the drug is and what the study found.

PALCA: Well, the drug is called molnupiravir, and it was originally developed by scientists at Emory University and Vanderbilt University. And as you said, it's an antiviral drug that blocks the ability of the coronavirus to replicate. It's a little bit analogous to the drugs people infected with HIV take to prevent AIDS. The study was supposed to involve 1,550 volunteers, and these were all people with mild to moderate COVID-19 but who were at risk for severe disease. And they were enrolled in the trial within five days of symptom onset. Half got the drug, and half got a placebo. Now the trial was blinded, meaning the company didn't know who was getting what. But a special independent committee did know. Most trials have such committees to make sure that the drug isn't doing something bad or, as in this case, if the drug is clearly doing something good. So the committee looked at the data from the first 775 volunteers and said, woo (ph), this is working, you can stop the trial.

SHAPIRO: So how well was it working?

PALCA: Well, very well. Here's how Anthony Fauci described the results at a White House briefing earlier today.


ANTHONY FAUCI: In the placebo group, there were eight deaths, and in the treatment group there were no deaths. That's very good news.

PALCA: They also looked at hospitalizations. Fourteen percent of the people in the placebo group were either hospitalized or died, while only 7% in the treatment group were hospitalized. And as Fauci just said, no one died.

SHAPIRO: So what does this mean for the pandemic?

PALCA: Well, it's clearly good news. It's probably better news for individuals than it is for the pandemic as a whole. There is already a treatment called monoclonal antibodies that works even a little bit better than this new drug does. But the monoclonal antibody is more complicated to administer and much more complicated to make. And this is a pill. And having a pill could simplify treatment enormously. But I spoke with infectious disease doctor William Schaffner from Vanderbilt University Medical Center, and although he was very positive about the new results, he also had a warning.

WILLIAM SCHAFFNER: It should not - it should not be a substitute for vaccination. Vaccination on the front end to prevent the disease as much as possible - that way is much better than having to treat it once the illness occurs.

SHAPIRO: So realistically, Joe, how soon are patients likely to be able to get this drug?

PALCA: Well, Anthony Fauci spoke to that issue also today at today's White House briefing.


FAUCI: The company, when they briefed us last night, had mentioned that they will be submitting their data to the FDA imminently.

PALCA: Now, how long the FDA takes to make a decision is, of course, uncertain. But it usually will come - these have been coming rather rapidly, so it could be weeks or possibly months. But the United States, interestingly enough, has already struck a deal with Merck to purchase 1.7 million courses of therapy once the drug is authorized for sale. So I guess they think it's coming.

SHAPIRO: And are more drugs like this in the pipeline?

PALCA: Yeah. Interestingly enough, both Roche and Pfizer - those are two large drug companies - are making similar drugs. And, you know, when something like this shows positive results, it's likely to spur efforts by other companies to make something similar.

SHAPIRO: NPR's science correspondent Joe Palca, thanks a lot.

PALCA: Oh, you're very welcome. Transcript provided by NPR, Copyright NPR.