Merck (NYSE:MRK) recently won U.S. Food and Drug Administration approval for its pneumococcal vaccine. Pfizer (NYSE:PFE) currently dominates the pneumococcal vaccine market, with its Prevenar 13 generating nearly $6 billion in sales last year. In this Motley Fool Live video recorded on July 21, healthcare and cannabis bureau editor-analyst Olivia Zitkus and Motley Fool contributor Keith Speights discuss whether or not Merck can beat Pfizer in this multibillion-dollar vaccine market.

Olivia Zitkus: We'll go back to Pfizer and I want to talk about Pfizer and Merck and move away from COVID for just a moment. Pfizer obviously gets a lot of attention for its COVID vaccine, but the company actually makes billions of dollars every year from its pneumococcal vaccine, Prevnar 13.

It recently won FDA approval for the successor to Prevnar 13, Prevnar 20, very original. Merck also just won FDA approval for its pneumococcal vaccine, Vaxneuvance, which is previously V114.

This only came a month after Pfizer's approval. Do you think that Merck could beat Pfizer in this multi-billion-dollar market? It looks like they're shaping up to compete, but what are your thoughts here?

Keith Speights: Yeah, I think this is an interesting competition here. Merck's vaccine addresses 15 pneumococcal strains and that's two more than Pfizer's Prevnar 13. The numbers come from the number of strains that they address, Prevnar 13 addresses 13, Merck's vaccine addresses 15. But Pfizer's new Prevnar 20, surprise, surprise, targets 20 strains [laughs] and so it has broader coverage.

Those additional seven strains that Prevnar 20 addresses versus Prevnar 13, accounts for around 40% of all of the pneumococcal disease cases and deaths in the United States. Those extra seven strains for Prevnar 20 are quite significant. Keep in mind this, one of the additional strains that Merck's vaccine covers compared to Prevnar 13, is the top cause of pneumococcal disease in adults in the U.S., so Merck has a distinct advantage over Prevnar 13.

How is this going to shake out? My view is that, Pfizer has the upper hand in the adult market simply because its vaccine provides more protection than Merck's vaccine does. I think you're going to see Pfizer win out over Merck in that space.

Where Merck could win is in the pediatric market. The company expects to file for FDA approval of its pneumococcal vaccine in kids by the end of this year. Pfizer doesn't even expect to report its late-stage data for pediatric use until 2022. I think there is a really good chance that Merck is going to have at least a couple of years, but close to it, on the market in the pediatric indication by itself, so Merck really could beat Pfizer in that particular part of this market.

Zitkus: Awesome. Children make up to, I think, close to 80% of that market opportunity. That could be huge. I know that Pfizer received a big bump when Prevnar was approved for use for adults 65 and older, which is the other main target group of this vaccine, back in 2014, but children do make up the majority of the market, so that could be big for Merck.

Speights: Right. Merck's advantage could only be short lived, because again, Prevnar 20 has more coverage. Assuming Pfizer does come along and win approval in the pediatric indication, it could then become the big player in that market as well. Both of these companies will probably have success with these vaccines.

Zitkus: OK, Great. Something to watch as they battle it out already.

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