What happened

The stock of top coronavirus vaccine maker Moderna (MRNA 0.89%) was doing well on Wednesday. In mid-afternoon trading it was outpacing the S&P 500 index with a 1.3% rise; it seems an article published in The New York Times earlier in the day helped bring some investors back into the stock.

So what

Citing several recent research studies, the Times wrote that Moderna's mRNA-1273 appears to provide more durable long-term protection against the coronavirus than Pfizer (PFE -0.19%) and BioNTech's (BNTX -0.45%) Comirnaty.

A person receiving a vaccination from a health provider.

Image source: Getty Images.

In particular, research from the Centers for Disease Control and Prevention found that the Pfizer/BioNTech jab's efficacy dropped notably from 91% to 77% four months after the second of its two doses was administered. For mRNA-1273, that did not change.

The Moderna and Pfizer/BioNTech vaccines, plus a one-shot vaccine from pharmaceutical giant Johnson & Johnson's unit Janssen, are the three that have received a green light from the FDA for use. Of the trio, so far only Comirnaty has received full regulatory approval; the other two are still distributed and administered under Emergency Use Authorization.

The efficacy and durability of the vaccines is particularly of concern now because health authorities such as the FDA are considering booster doses for people who have been vaccinated.

Now what

Professional opinion differs on the importance of these recent findings, with some medical experts saying they are significant and others expressing a more skeptical view.

It's important to note that we are still at a relatively early stage with coronavirus vaccines, as they were authorized less than a year ago. More research must be done into other factors behind them to get a better understanding of efficacy over time.