Another major coronavirus wave might be in store for Americans. The Biden administration warned in May that there could potentially be 100 million COVID-19 cases this fall and winter.

However, the U.S. Food and Drug Administration (FDA) has cleared the path for omicron-targeting boosters to be available this fall. These boosters should provide additional protection against coronavirus infection. 

This should be especially good news for Moderna (MRNA 3.32%). The vaccine stock has plunged nearly 70% below its 52-week high. But is Moderna now a no-brainer buy with omicron boosters on the way?

Two hurdles

A no-brainer decision is one that requires practically no mental effort. I think we can safely determine that some mental effort is needed when it comes to buying Moderna. After all, the company still has to jump two hurdles before it can achieve success with its omicron booster.

The first hurdle is that Moderna must obtain FDA Emergency Use Authorization (EUA) for its omicron booster. The FDA's recent decision only advised vaccine manufacturers that they should include an omicron component in boosters to be used beginning this fall. It didn't actually authorize any specific omicron boosters. 

The second hurdle for Moderna is to secure an additional supply deal with the U.S. government that includes omicron boosters. Pfizer (PFE 0.01%) and BioNTech (BNTX 0.58%) announced a new supply agreement with the U.S. on June 29. The U.S. government will buy 105 million doses of the Pfizer-BioNTech COVID-19 vaccine for $3.2 billion. Those doses could include the two companies' omicron-targeting vaccine version.

There is a potential wrinkle with Moderna landing a new U.S. contract. Moderna's current deal with the U.S. is for 500 million doses. However, only around 286 million doses have been delivered so far. The federal government has a lot more doses remaining on its contract with Moderna than it did with Pfizer and BioNTech before placing an additional order.

Assuming the best

Let's assume, though, that the best scenario plays out for Moderna with these two hurdles. Suppose the company wins EUA for its omicron booster and signs a new supply agreement with the U.S. Would checking off those boxes make the stock a surefire candidate to buy? Not really.

Sure, it would be great for Moderna to increase its revenue this year by $3 billion or so. (There's no guarantee that the U.S. would order as many additional doses from Moderna as it did from Pfizer and BioNTech, but we're going with a best-case scenario here.) But this still wouldn't remove the uncertainty about the future of the COVID-19 vaccine market.

No one knows what the demand for vaccines will be beyond 2022. Even if demand remains strong, it's quite possible that the dynamics of the market will be shaken up by combination COVID/flu vaccines. The side effects of Moderna's combo vaccine could put the company at a disadvantage compared to Novavax.

Moderna does have other promising pipeline candidates. However, it will remain solely dependent on COVID-19 vaccine revenue for at least a few more years. Until the uncertainty surrounding the market for these vaccines is resolved, Moderna is far from a no-brainer buy.

Making a case for Moderna

Some investors might find Moderna attractive, though. The stock trades at only six times expected earnings. The average Wall Street price target for Moderna reflects a premium of more than 40% over the current share price.

The U.S. and other countries could require annual COVID-19 boosters for years to come. Over the long term, Moderna's messenger RNA platform could deliver multiple game-changing vaccines and therapies. 

Moderna isn't a no-brainer stock to buy right now. But that doesn't mean that investing in the stock is the wrong decision. It's just a risky one.