Regeneron Pharmaceuticals (NASDAQ:REGN) and its partner, Roche (OTC:RHHBY), recently reported positive results from a late-stage study of COVID-19 antibody therapy REGEN-COV as a prophylaxis. In this Motley Fool Live video recorded on Nov. 10, 2021, Motley Fool contributors Keith Speights and Brian Orelli discuss why these results probably won't lead to significantly higher sales for the therapy.

Keith Speights: All right, let's switch to some different COVID-19 news here. Regeneron and Roche, its partner, reported positive results this week from a phase 3 study of their COVID-19 antibody therapy REGEN-COV.

Brian, what do you make of those results? Are they likely to impact Regeneron's sales going forward?

Brian Orelli: This was a study using the drug as a prophylaxis to prevent COVID-19 because another member of the family had developed COVID. Previously, the company had showed that it prevented the risk of developing COVID by 81.4% in the first month after treatment. So that would've been measuring mostly interaction with the family member.

Then they just followed the patients because they had them, and they just continued the study. Then they looked at this new data, it's looking at months two to eight, where the treatment reduced the risk of developing COVID by 81.6%. In that case, they're probably not [at risk of catching it] from the family member, because that family member would've gotten better likely in the first month.

Now, we're just looking at general exposure. Compared to placebo, it reduced the risk of developing COVID by 81.6%. Looking at hospitalizations over those eight months, there were six in the placebo group and zero in the group that got REGEN-COV. So not only is it preventing infections, but it's also preventing severe disease.

Now, will it do anything for the sales? Maybe there's a subset of patients who might take this as a prophylaxis. I'm thinking specifically people with compromised immune systems that might not react to the vaccine. But I don't see it being used as a prophylaxis as having a huge impact on sales. I think most of the sales will be due to treatment, although they're going to have competition from oral treatments.

Speights: Yeah, you mentioned the oral treatments. We have spoken in the past, when Merck (NYSE:MRK) and Ridgeback had their great results. We talked about how that could negatively impact Regeneron here. But now, Pfizer (NYSE:PFE) has even better results. What's the outlook for Regeneron's REGEN-COV with the potential for both Pfizer and Merck to have highly effective COVID-19 pills on the market?

Orelli: I mean, except for the fact that they may be limited in the number of doses that they'll have available. But beyond that, I mean, I can't see why a doctor would prescribe REGEN-COV over the oral treatments, mostly just out of convenience more than anything else, especially since you have infusions versus pills.

Speights: Yeah. Give me a pill any day instead of getting stuck.

Orelli: Right. Plus you don't have to go to the doctor's office. Once you test positive, you can just send a family member to the pharmacy and go get your pills, and then take them at home. It also protects healthcare workers, as well, from getting COVID-19.

Speights: Basically, Regeneron is probably enjoying its best days right now with REGEN-COV, probably. I think the company will still see strong sales probably into the first half of next year. But after that, it could be a really different story, I think.

Orelli: Yeah. And the government has been buying all of the REGEN-COV, so I think that you probably won't see another sale of REGEN-COV to the government, would be my guess.

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