Eli Lilly (LLY -1.11%) is the most valuable healthcare stock in the world, with a market capitalization north of $800 billion. In the past 12 months, its shares have risen by more than 50%, and while its growth prospects look strong, investors may balk at paying a multiple of more than 100 times its trailing earnings.

However, while Eli Lilly‘s valuation may look pricey, that shouldn’t dissuade you from potentially adding the stock to your portfolio. Here are three reasons why its valuation can continue to surge even higher in the months and years ahead.

1. The potential for tirzepatide could still be underrated

In the past couple of years, Eli Lilly has secured some key approvals from the Food and Drug Administration (FDA) that have made investors bullish on its long-term prospects. Regulators approved Zepbound (for weight loss) and Mounjaro (diabetes). Both drugs share the same common ingredient, tirzepatide, and they are still in their early growth stages.

While expectations are high for these treatments as analysts expect tirzepatide could generate $50 billion in revenue (or more) at its peak, it’s possible that it ends up exceeding that potential. That’s because it could end up accumulating more indications along the way. Zepbound, for example, has shown in clinical trials that it can reduce the risk of heart failure. In another study, it has demonstrated its effectiveness as a treatment for sleep apnea. It could obtain approval for those and other indications in the future, which could bolster its growth prospects.

There’s a lot of potential for tirzepatide, and that’s why, although the peak appears high, it could be even higher in the future if the FDA approves more indications for the drug.

2. The company is increasing capacity, which should accelerate growth

A big hindrance for Eli Lilly these days is capacity. Demand is soaring for Mounjaro and Zepbound, which has led to people turning to knockoff drugs that promise to be as effective. It’s a potentially dangerous solution, but it highlights just how much interest there is in these drugs.

Eli Lilly is, however, investing in its capacity to ensure that it can help produce enough of these products to meet demand. The healthcare company will spend $9 billion on a new production site in Indiana, which is the largest such investment it has ever made in its history.

Ramping up production can help accelerate Eli Lilly’s already strong results, which could trigger even more bullishness in this already hot stock. Through the first half of the year, Eli Lilly’s sales have totaled $21 billion, rising at a rate of 31% year over year.

3. It’s investing heavily in growing its pipeline

What’s most attractive about Eli Lilly is that the company is still investing for future growth. This isn’t a company that is content with the status quo. In a recent interview, CEO Dave Ricks said he wanted Eli Lilly to “exploit” the lead it has in the anti-obesity market rather than simply maintaining it.

Those efforts are underscored by a $4.5 billion investment Eli Lilly recently announced to create a research and manufacturing center, which will help it focus on newer, more efficient procedures, which, in turn, can help with the development of new drugs. The goal is to combine both research and production efforts in one place, which can help bolster its already robust pipeline.

It isn’t too late to invest in Eli Lilly

Investors are undoubtedly paying a high premium for Eli Lilly shares now, but given the phenomenal growth on its horizon, it’s a justifiable price tag for the business. The stock looks on track to be the first healthcare company to join the $1 trillion club in the future. It’s one of the safer growth stocks you can invest in today, and as its earnings numbers grow, its earnings multiple will come down, and Eli Lilly will appear more modestly valued.

As long as you’re willing to buy and hold for the long term, Eli Lilly can make for an excellent investment to put in your portfolio today.