Investors should never ignore valuations when picking stocks. The price a stock trades at can drastically impact your overall returns. A metric such as the price-to-earnings (P/E) ratio can be helpful in enabling you to easily gauge how expensive or cheap a stock is.

In some cases, however, it can make sense to buy a stock that's trading at a seemingly high P/E multiple simply because of its fantastic growth prospects. If you wait for a top growth stock to come down to a P/E of 20 or less, you may end up waiting forever and missing out on the opportunity completely.

Below, I'll make the case for why pharma giant Eli Lilly (LLY -3.00%) still looks like a great buy right now -- even though it trades at a P/E of more than 70 -- and why selling the healthcare stock could be a mistake.

Eli Lilly's growth has been accelerating -- and that could continue

For years, Eli Lilly has been generating solid growth numbers -- but lately, they've been accelerating rapidly. The company is coming off a solid quarter where its revenue rose by 45% for the last three months of 2024:

LLY Operating Revenue (Quarterly YoY Growth) data by YCharts.

The recent surge has been due to the tremendous growth Lilly has achieved due to its highly popular GLP-1 drugs, including Mounjaro (for diabetes) and Zepbound (for weight loss). Together, those two products generated $5.4 billion in sales for Eli Lilly last quarter, or 40% of the top line.

Demand has been so strong that shortages of Lilly's GLP-1 drugs have been an issue. The company has been investing billions of dollars into increasing its production capacity at a manufacturing site in Lebanon, Indiana. And as it begins producing medicines there, potentially as early as next year, that could help boost its sales.

A new drug could open up even more growth potential

Eli Lilly is still in the early stages of its growth when it comes to GLP-1 treatments. The drugs are game changers for patients, helping them lose weight and become healthier in the process. Currently, Lilly's GLP-1 treatments are injectables.

However, by next year, the company may have an even more attractive option for patients: a highly effective oral weight loss drug called orforglipron. By April, the company expects to release late-stage trial data for the drug, which has previously shown that on average, it can help people lose around 15% of their body weight. If the new trial results are strong, they could pave the way for approval by sometime next year.

Approval for orforglipron would not only generate a lot of bullishness for the healthcare stock, but would also provide Eli Lilly with yet another blockbuster drug, and potentially enable it to reach a broader range of patients.

Lilly looks poised to hit a $1 trillion market value

Shares of Eli Lilly haven't been doing well in recent months, but over the long run, I think they will more than recover. This is a company whose valuation could very well top $1 trillion within the next year or two. Its market capitalization sits around $780 billion now, and reaching that pinnacle would require the stock to rise less than 30% from where it is right now.

Lilly's P/E ratio may appear high now. But as the company scales up its operations and its profits rise, that multiple will come down, so I wouldn't be overly concerned with it. Given its robust business and terrific portfolio of drugs, you're likely better off simply buying and holding the stock rather than waiting for the P/E to come down, as doing so could result in missing out on some terrific gains along the way.

And while current shareholders may secure a good profit by selling it today, unless they need the money for other reasons, there's no compelling reason to sell -- this is a stock which still has a ton of upside in the long run.