The COVID-19 vaccine market is getting more crowded. Johnson & Johnson (NYSE:JNJ) recently won U.S. Emergency Use Authorization (EUA) for its vaccine. And now Sanofi (NASDAQ:SNY) and GlaxoSmithKline (NYSE:GSK) plan to kick off a phase 2 study of their COVID-19 vaccine. In this Motley Fool Live video, recorded on Feb. 24, Fool.com contributors Keith Speights and Brian Orelli discuss whether or not Sanofi and GlaxoSmithKline might be too late to the party.

Keith Speights: Let's talk for a second about Sanofi and GlaxoSmithKline. Tickers there for Sanofi is SNY, for GlaxoSmithKline, ticker is GSK. These two companies announced that they're starting a phase 2 study of their COVID-19 vaccine candidate. They had some delays and now they're back on track to some degree anyway.

They expect to begin a phase 3 study in the second quarter if all goes well. Again, if all goes well, they look for the vaccine to potentially be available and authorized in the fourth quarter. But Brian, do you think these companies are maybe too late to the party?

Brian Orelli: I think it depends a lot on when, in the second quarter, it's going to start. If it's going to start toward the end of the quarter, that's going to be when a lot of people have already been vaccinated.

We'll just have enough doses at the end of July for 300 million people. That's basically all adults in the United States. Just from the two vaccines and then we haven't even added in whatever Johnson & Johnson could be able to provide at that point.

I think the problem becomes for these later companies determining efficacy as the rate goes down, the length of time it's going to take you to get the different levels of infection between placebo and your group that gets the vaccine is going to be longer and longer as there's less and less people that get infected in the placebo group.

Then plus on top of that, as more and more people get vaccinated, and there's more and more vaccine available, less and less people are going to want to be involved in a clinical trial that's placebo-controlled if have a 100% chance of getting the vaccine and a 1 in 2 or 1 and 3 chance of getting placebo in the clinical trial. That makes it a lot less. There's going to be lower appetite for clinical trials when there wasn't any vaccines available.

Speights: I think some of these companies really may be more of a factor in a post-pandemic world with their vaccines, and that could be true for Sanofi and Glaxo.

Orelli: I'm sure that's what they're going for, but I still think it's going to be really difficult for them to actually show that their vaccines work. They may have to go into other countries where the infection rates are still much higher to be able to show, or they're going to have to run a really long clinical trial would be my guess.

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