In this video from Motley Fool Live, recorded on Feb. 1, Contributors Brian Orelli and Keith Speights discuss the phase 3 clinical trial results for Johnson & Johnson's (NYSE:JNJ) coronavirus vaccine. While the efficacy wasn't as good as the vaccine from Moderna (NASDAQ:MRNA) and the one from Pfizer (NYSE:PFE) and BioNTech (NASDAQ:BNTX), Johnson & Johnson's clinical trial had more exposure to the new coronavirus variants. Johnson & Johnson's one-shot format also makes it easier to deliver to rural areas.

Brian Orelli: First off, we have phase 3 data from Johnson & Johnson that was released last week. In the United States it had a 72% efficacy. In Latin America 66%. In South Africa, all the way down at 57%. I don't think that's really too surprising considering this new variant in South Africa and Latin America, and this was designed to express the original spike protein. It's not too surprising to see lower efficacy in South Africa and Latin America than in the United States. Overall, 66% efficacy when you average those three out based on how many people were in each of the areas.

Interestingly, they only looked at moderate to severe COVID-19. The other companies that have released phase 3 data for U.S. studies of Moderna and Pfizer and then BioNTech have all looked at all forms, including the mild form. Any thoughts on why Johnson & Johnson didn't include mild?

Keith Speights: I guess, Brian, some people might immediately think they're just trying to boost their overall efficacy numbers. But I don't think that holds water because remember, there would have been plenty of mild cases in the placebo group as well. My best guess is Johnson & Johnson was just focusing on the important task at hand, which is to prevent the spread, prevent the infection of moderate to more severe cases. I think that's probably what they did. But I don't think they actually came out and explained why they chose not to include mild cases in their analysis as some of the other companies did. Have you come across anything the company itself has stated about that?

Orelli: I didn't hear anything. It was surprising to me. I didn't even notice it until somebody else had pointed it out in the press release.

Speights: There's no reason to think that their efficacy would've been higher or lower necessarily had they included mild cases. I think we just don't know.

Orelli: Yeah. I think the issue is, we don't know, but maybe if it is not working quite as well then there might be just as many mild cases in both of them. If it's working but not producing enough antibodies to keep people in the mild state, but not producing enough antibodies to keep people from having any symptoms. We're talking about symptomatic COVID-19. If you're not symptomatic. You're not going to get the test, therefore you're not going to test positive even though you may actually have the virus in your bloodstream.

Speights: I did see that J&J said that their definition of moderate cases was if a participant had any one of several different symptoms that they had on the list. They didn't provide that list, at least in the statement that I saw. One of those symptoms would classify someone as moderate. Some of these companies definition of mild to moderate could be different than the next companies.

Orelli: Yeah, that's definitely true. I think obviously preventing disease is the most important. If everybody is only getting the mild cases then it's really not as bad of a pandemic.

Speights: Yeah, exactly. If every case of COVID-19 was mild, we wouldn't be in the situation we're in right now.

Orelli: Right. We'd be talking about the common cold basically.

Speights: Yeah. You and I would be having a totally different discussion this morning.

Orelli: Right. Then for the effectiveness, it was at 66%. Moderna and Pfizer and BioNTech have been closer to 95%. I think it's hard to read through because there is so many new variants that are circulating and this clinical trial was run later than the other ones. I think that that's probably hard to compare that 95% to the 66%.

Speights: Yeah, it is. And remember this is a single dose vaccine versus two doses for Pfizer, BioNTech vaccine and the Moderna vaccine. I'm trying to remember, Brian. I think the Pfizer vaccine after the first dose is achieved maybe a 52% efficacy or something like that. Johnson & Johnson's results are significantly better than what we've seen from the single-dose of Pfizer. I think that's the thing to keep in mind that a single dose vaccine, there's definitely some advantages and this isn't necessarily bad efficacy at all for one dose.

Orelli: Yeah, they are testing two doses.

Speights: OK.

Orelli: But I don't think that this is expected until late summer or early fall. That's going to be a while. I'm not sure that we're going to get as much of a boost from the second dose as the Moderna and Pfizer and BioNTech just because of the way they are designed. Moderna, Pfizer and BioNTech are all using mRNA, where Johnson & Johnson is using an adenovirus to deliver the DNA which then gets made into mRNA which then makes the protein that our bodies will react to. I think that there may be a reaction to that adenovirus as well. The second dose may also attack the virus before it can get into the cells and that may have some problems with boosting the second dose.

Speights: Yeah. Brian, I think some people might have been disappointed when they saw the Johnson & Johnson results. What was your take? Did you think it was disappointing or do you think it was middling or what was your taking?

Orelli: The FDA has always said 50% is enough to get emergency use authorization. Certainly anything above 50%, anything above in the 66% range, especially in the U.S. it's 72 if we don't start having variants, I think it's pretty good and certainly going to help reduce the spread. As you're reducing the spread then that ultimately will help us get rid of the virus. Obviously I'd rather have 95% for everything. I think it's disappointing in that respect, but probably not disappointing in the overall scheme of things. If it gets more people vaccinated quicker, then it's helpful.

Speights: Absolutely. I hate to put it this way but I think in some ways, the public might've been spoiled a little bit by seeing those stellar results from Pfizer and Moderna already. I think the expectations were raised maybe abnormally or too high, higher than they should have been.

Orelli: Yeah, I would say on that after Pfizer and BioNTech did theirs before, we had the Moderna results, which is only there was like a week something between those two. I was saying I was 95% too high, and then they come out basically almost the exact same thing.

Speights: Yeah.

Orelli: Which I guess is not too surprising.

Speights: You know this, but I think just in the historical context, 95%, 94% efficacy is outstanding for a vaccine. Flu vaccines are maybe on the 60% efficacy range, something like that. To have something that's 90% or higher is absolutely fantastic, and we had two brand-new vaccines come out with that efficacy and I think many people may not realize just how good that really is.

Orelli: Wrapping it up here with Johnson & Johnson, you think it's enough to get an emergency use authorization from the FDA?

Speights: Absolutely. I think there's a big need for a single-dose vaccine. I think it will sail through the emergency use authorization process. What about you?

Orelli: Yeah, I totally agree. Yeah, I know it fits. Anything above 50% is going to get through without a doubt. There weren't any safety signals that would make you think that it wouldn't pass.

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