Moderna's (MRNA -0.62%) success in the coronavirus vaccine race has equaled success for early investors. Those who bet on Moderna as it brought a vaccine candidate into clinical trials back in the spring of 2020 have benefited. The biotech then launched its vaccine, generated billions of dollars in revenue from it, and saw its shares take off.

Since then, the stock has declined from its peak. But it still represents a winning investment for those who got in on the story early. Let's take a look at how much you would have today if you'd invested $5,000 in Moderna back in 2020.

178 shares of Moderna

Moderna became one of the first to bring a coronavirus vaccine candidate into clinical trials. That happened three years ago, in the spring of 2020. Let's imagine you bought your shares on March 19, when they traded for about $28. With $5,000, you would have purchased about 178 shares.

Today, with the stock trading around $150, your investment would be worth $26,700. That's reason to cheer.

Still, you may regret you didn't sell earlier -- because at the stock's peak in August 2021, your investment climbed to a value of $86,152. That, of course, represents an amazing return.

But if you've held on to Moderna, don't despair. First, you've still won. Second, you may be setting yourself up for a bigger win over the long term. That's because there likely is a lot of growth ahead for Moderna. And that should lead to more share price gains.

You may be thinking, "Now, wait a minute... vaccine demand is declining. That's going to hurt growth." And you're right. The company won't be able to rely on its coronavirus vaccine forever. And in the near term, the drop in vaccine demand is set to weigh on earnings.

However, sales growth linked to a pandemic situation can't truly be compared to sales growth during ordinary times. Once Moderna starts selling its vaccine in a post-pandemic world, then we'll have an idea of what sales over time could look like -- and we'll have a better comparison point.

A year of transition

This year should be a transition into that new environment. And there's reason to be optimistic the coronavirus vaccine will continue to generate blockbuster revenue -- even if this revenue doesn't reach pandemic levels.

Moderna predicts the vaccine will follow the path of the flu shot. That means about half of the U.S. population could eventually opt for an annual coronavirus jab. So the biotech still could bring in significant revenue from vaccines and boosters.

Meanwhile, the profit Moderna already has generated allows it to bring other candidates through the pipeline. And here, we're looking at three possible launches over the next few years. Each of these candidates represents a blockbuster opportunity for Moderna.

First, the company aims to submit its candidate for respiratory syncytial virus (RSV) to regulators by the end of the first half of this year. RSV is a common respiratory illness that's particularly dangerous for the elderly and infants. Moderna aims for approval in the older adult population -- a market that's worth more than $10 billion globally.

Moderna also has vaccine candidates for flu and cytomegalovirus (CMV) in phase 3 trials. So, they're close to the finish line.

All of this means the company could deliver a few sources of billion-dollar revenue within the coming years. This makes an investment in Moderna much less risky today than it was back in 2020.

Moderna shares probably won't take off as quickly as they did during the early days of the pandemic. Back then, investors piled into vaccine stocks considering the crisis situation -- and that drove share prices up.

But that's OK. Moderna still has what it takes to make impressive gains over time. Thanks to pipeline progress and a coronavirus vaccine that should continue to bring in billions, your investment could easily grow well into the future.