Major pharmaceutical businesses aren't known for their rocket-like returns, but they aren't known for experiencing total wipeouts either. That's why a quickly growing, yet already big company like Novo Nordisk (NVO 0.84%) is especially appealing for investment. In theory, it could have significant upside without too much in the way of catastrophic risk.

But could a timely and sufficiently sized investment in this biopharma be enough to make you a millionaire by the time you retire? It's more plausible than it might seem -- here's why.

How long will this company be on a tear?

Addressing whether Novo Nordisk is a stock that'll help you retire as a millionaire means appreciating what it's doing today and what it plans to do in the future. The company's cash cows of the moment include Ozempic, its medicine for type 2 diabetes, and a variation of Ozempic, called Wegovy, that's indicated for weight loss. The pair are tremendously hot sellers, bringing in nearly $5 billion in sales in Q3 of 2023.

Management expects demand to remain hot this year, and it's ramping up its manufacturing capacity to supply more to the U.S. market. As the market for weight loss and type 2 diabetes medicines is still growing, analysts at GlobalData estimate that Ozempic alone will bring in revenue of around $19 billion in 2029. For reference, the entire company's trailing-12-month sales currently total $31 billion, so a significant amount of growth is slated for the next few years.

While it's possible that competition from players like Eli Lilly could put a crimp in Ozempic's march forward, Novo Nordisk won't be sitting still. Its research and development (R&D) pipeline is investigating the molecule behind Ozempic, semaglutide, for a bunch of purposes beyond its original design, including for Alzheimer's disease and metabolic dysfunction-associated steatohepatitis (MASH).

While it might not succeed with 100% of these attempts, it has so many different programs that at least a couple are likely to proceed to commercialization, assuming regulators assent. Beyond that, it has various mid- and late-stage programs for treating other metabolic and cardiovascular illnesses. With roughly $7 billion in cash, equivalents, and short-term investments on hand, Novo Nordisk has more than enough resources to implement its plans over the coming years.

So, as far as biopharma businesses go, Novo Nordisk is in a strong position, and its near-term prospects are favorable. That bodes well for its potential as a fruitful investment for the purposes of saving for retirement.

This road to building wealth is going to be long

Now that we understand what this company is likely to be spending its time and resources on, let's calculate whether it's a good vehicle for wealth-building over the long term.

Novo Nordisk's annualized total return since its initial public offering (IPO) is nearly 18% per year, considerably better than the market's annualized total return of 10% per year. For the purposes of our projection here, let's use a more conservative figure of 15% for the stock's forward returns; without perfect knowledge of the future, we should assume returns will revert to the market's average over the long term.

Let's also look at the returns over a time horizon of 20 years and assume you'll keep building up your position by investing an additional $100 each month on top of an initial investment of $5,000. In other words, we're assuming that you're mid-career, and therefore, your target retirement date is still quite a distance away.

Under those conditions, in 2044, you might have roughly $205,000. After waiting another decade and continuing to invest -- making for an uninterrupted holding and investing streak of 30 years -- you'd have $853,000.

Obviously, neither of those figures is enough to make someone a millionaire on its own. Nor is there any guarantee that its winning streak will continue or that it'll even retain its value. But when considering the broader context of building up enough wealth for retirement, the picture is much sunnier.

Yes, Novo Nordisk could help you retire as a millionaire. If you purchase its shares via dollar-cost averaging (DCA) over a long period, there is a high chance you'll be better off than before. And with the help of the rest of your well-diversified portfolio, assuming you can invest diligently and consistently, you'll have a real shot at having total wealth in excess of $1 million. The hardest part is being patient along the way.