More than 40 coronavirus vaccine candidates are currently in development, according to the World Health Organization. Which of the companies behind these experimental vaccines should investors watch most closely? In this Fool Live video, Healthcare and Cannabis Bureau Chief Corinne Cardina and longtime Motley Fool contributor Keith Speights discuss three coronavirus vaccine makers that stand out right now.

Corinne Cardina: Diving into some of these specific stocks a little bit more. Obviously, the nucleic acid approach would be the most ground-breaking because the vaccines that use this approach have never been approved for use. I'm interested, are there any of these stocks that are ongoing, so Pfizer (NYSE:PFE), BioNTech (NASDAQ:BNTX), Moderna, Novavax (NASDAQ:NVAX) that really stand out to you, whether it's because their vaccine has a unique value proposition or you're particularly interested in the underlying business?

Keith Speights: There are actually three that I think stand out for different reasons.

First, I would just say Pfizer and BioNTech are probably, at least based on all we know right now, they're probably going to be the first to file for emergency use authorization. So I think that's definitely a vaccine that you'll want to watch because it could be the first one that becomes available to Americans.

I also am keeping my eye on Johnson & Johnson (NYSE:JNJ). Even though they've had to put their clinical trial on pause, I think it will just be temporary is my guess. The nice thing about Johnson & Johnson's vaccine is that it only requires a single dose. The other vaccines require two doses, and that could be a really big advantage if it ultimately makes it to market, because I think everyone would prefer only having to go get a shot once instead of having to get one and then going back a month later and getting another.

Then the third one that I'm really keeping my eye on is Novavax, and the reason why I'm watching Novavax particularly is Novavax is just so much smaller than any of these other players. Novavax has a relatively small market cap of around $7 billion or so. Most of these others are either huge, big pharmas like Pfizer, AstraZeneca, or even Moderna has a market cap of close to $30 billion. And so Novavax is smaller and if they succeed, I think that's going to be a start that could be the biggest winner of all, and it's actually been the biggest winner of all of these leaders so far this year.