What happened

Shares of Moderna (MRNA 0.15%) were sliding 5.1% lower as of 11 a.m. ET on Tuesday. The decline appears to be the result of some profit-taking after Moderna's shares jumped on Monday after the company's CEO, Stéphane Bancel, said during an interview on CNBC that Moderna will soon begin clinical trials for a version of its COVID-19 vaccine that specifically targets the coronavirus omicron variant.

So what

It's really not all that surprising that Moderna's bounce didn't last long. There's a good argument to be made that the vaccine stock rose more than was warranted on Monday.

A scientist holding a vaccine vial with another scientist in the background.

Image source: Getty Images.

Investors were pleased that Moderna is moving forward relatively quickly with its omicron-specific vaccine. However, the company will still be behind Pfizer and BioNTech. Pfizer CEO Albert Bourla said on Monday that the Pfizer-BioNTech vaccine version targeting omicron will be ready by March.  Bancel indicated that Moderna's omicron-specific vaccine should be ready by the fall.

An even greater concern, though, is that Moderna and the Pfizer-BioNTech team will be too late to the party. The current wave of COVID-19 cases due to the omicron variant will likely be over or largely over before either new vaccine version is available. 

Now what

Perhaps the most important thing to watch with Moderna now is how quickly efficacy wanes for natural infections and current vaccines with the spread of the omicron variant. Although Moderna's omicron-targeting vaccine won't be of help in the near term, it could be needed in the not-too-distant future.