Moderna (MRNA -2.21%) has posted major gains for two straight years. In 2020, investors bet on the biotech company's ability to bring a coronavirus vaccine to market, and they won. Moderna scored Emergency Use Authorization and finished the year with a 434% share gain. This year, Moderna shares have advanced another 192%. That's after the company reported billions of dollars in revenue and profit every quarter.

Now, as we head toward 2022, you may be wondering if this dynamic biotech company can keep up the momentum. Are we reaching the final chapters of the Moderna investment story? Or is there a lot more to come? In 2022, we can buy, sell, or hold Moderna stock. Let's see which option might offer us the best return down the road.

An investor smiles as he reads something on his computer.

Image source: Getty Images.

The story so far

First, let's catch up on the Moderna story. The biotech launched its vaccine about a year ago, shortly after that of bigger rival Pfizer, which has vaccinated the most Americans (although Moderna remains a close second). It's fair to say both are market leaders. Moderna predicts vaccine sales of $15 billion to $18 billion this year. That's according to deliveries of its 2021 orders.

Investors rallied behind Moderna for most of this year. But some started to lose confidence in the stock's potential in recent months. As a result, shares slid 37% from a high reached in August. The problem? Investors worried Moderna's vaccine sales would slip as the pandemic eases -- and eventually drop significantly.

I think those worries are overdone. Experts have said for a while now that the coronavirus will continue to circulate post-pandemic. That means vaccination wasn't just a one-time thing. Vaccine performance so far, and the emergence of variants of concern, show us that we could need doses regularly. Pfizer's CEO and others have mentioned once a year as a possibility.

And speaking of Pfizer, a company executive recently said COVID-19 could move from pandemic to endemic by 2024. Some regions might reach this point earlier (as soon as next year), but it's clear the coronavirus threat is far from over.

Moderna already has locked in purchase agreements for vaccines and boosters through 2024. And more will probably roll in, especially considering recent events. The rapid spread of the omicron variant and massive increases in cases could spur countries to take action and secure orders.

Advancing booster candidates

Right now, Moderna is moving forward with several strain-specific booster candidates. The most advanced are in phase 2 trials. And the company has even started the development of an omicron-specific candidate. What's important here is developing a method to quickly produce a booster that can handle the variant of the moment, as we see each year with the flu vaccine. Moderna may be on its way to doing this. Meanwhile, its authorized booster, a third vaccine jab at a lower dose, has shown the ability to handle variants including omicron.

All of this means it's unlikely Moderna will see a big drop in vaccine sales anytime soon. So the coronavirus vaccine business could power its shares higher in the coming year. At the same time, long-term investors will like the fact that Moderna isn't only about the coronavirus vaccine. The company has 37 programs in the pipeline across various therapeutic areas. And another potential blockbuster may be on the horizon. Moderna recently launched a pivotal trial for its cytomegalovirus (CMV) vaccine candidate.

Buy, hold, or sell?

So, let's get back to our question. Should you buy, hold, or sell Moderna shares in 2022? Overall, I vote for buying or holding -- that's because there's so much more ahead for this innovative company. Next year and beyond.

Investors who bought Moderna in its early days may want to sell some shares to lock in gains. And that's understandable -- it's even advisable. After all, biotech companies do come with a certain dose of risk. A clinical-trial failure, for example, could crush share performance. And increases in the future may not come at the same rate as those of the past two years.

But over the long term, Moderna has the pipeline, technology, and resources to keep on winning. And that means investors who stick around for a while should score a big win, too.