Novo Nordisk (NVO 0.02%) has an incredibly promising asset in Wegovy. The drug is approved for treating weight loss in multiple countries, and it's achieving some impressive revenue growth. 

The biggest challenge for analysts and investors is determining just how big its potential may be. That's because it can treat much more than just weight loss.

Wegovy's coverage could soon be much broader

In 2021, the Food and Drug Administration (FDA) approved Wegovy to help treat people with chronic weight management in adults with obesity or who are overweight with at least one weight-related medical condition. It was a monumental decision as it was the first such treatment approved since 2014. And with weight gain putting people at risk of many illnesses, there's the potential for Wegovy to help in many other areas. An example of that is cardiovascular disease. In clinical trials, Wegovy has shown that it can help reduce the risk of a heart attack or stroke by as much as 20%. Novo Nordisk says that within six months, the FDA may expand Wegovy's approval so that doctors can also prescribe the drug to patients who are at high risk of cardiovascular disease.

Further down the road, there's also the potential for even more indications. A study has shown that semaglutide, the active ingredient in Wegovy, has been effective in improving fatty liver disease for people with type 2 diabetes. Wegovy and other weight-loss drugs may also be helpful in curbing addictions given how they help control parts of the brain and reduce cravings.

The anti-obesity drug market is growing at a compounded annual growth rate of 26.1%, and it could generate sales of just under $23 billion annually by 2030, according to estimates from Fortune Business Insights. That is already a huge market for Wegovy to be in, and it can help create significant revenue for Novo Nordisk. But as massive as the opportunity already is for Wegovy, there's clearly room for it to get bigger and reach even more patients.

Weight-loss drugs are playing a huge role in Novo Nordisk's growth

Novo Nordisk's business centers around diabetes and obesity care. There's some overlap there as people have been using Ozempic, its top diabetes medication, as a treatment for obesity as it helps with weight loss. The big problem today is that drug shortages are resulting in customers using drugs off-label for indications they aren't yet approved for.

That's a key reason why over the past nine months, sales of Ozempic are up 53% year over year. Wegovy, however, which is in much earlier stages of its growth, has seen its revenue rise by 481% this year. Wegovy and Saxenda, the other weight-loss product in Novo Nordisk's portfolio, have helped the company's obesity-care segment generate growth of 167% over the past nine months. Obesity-care sales of 30 billion Danish krone ($4.3 billion) account for 18% of Novo Nordisk's sales this year versus just under 9% at this stage in 2022.

The company is investing $6 billion to expand its production capacity, which can address the shortage issues and lead to more growth in the future. But it's a process that will take years, with Novo Nordisk expecting the construction of new facilities to be gradual and not fully complete until 2029. But it's a positive sign that shortages shouldn't weigh down Wegovy in the long run.

Is Novo Nordisk stock a buy?

Novo Nordisk's stock trades at 42 times its trailing earnings and is around its 52-week high. It has made for an excellent investment this year as its shares are up by 50%, while the S&P 500 has risen by only 15%. While it may appear to be expensive, it may still be a good buy given that Wegovy's sales could be much more significant in the future due to label expansion and additional production capacity. And with more rapid growth in its future, the company's earnings should improve significantly, which makes today's valuation far more tenable for long-term investors.

As long as you're willing to buy and hold the healthcare stock for multiple years, Novo Nordisk can still make for a great investment.