Eli Lilly makes medicines that patients take every day, often for the rest of their lives. The company earns money by selling those medicines to pharmacies, hospitals, and health plans in about 90 countries. Its biggest products right now are Mounjaro and Zepbound, two medicines that treat type 2 diabetes and obesity. Because patients need refills continuously, revenue does not depend on one-time purchases. That makes the model look more like a utility than a store. The diagram below traces where the money goes.
Five years of numbers tell a story of rapid acceleration. Revenue held fairly flat from 2021 to 2022, then jumped as newer medicines took hold. By 2025 the company was reporting $65.2 billion in annual revenue, more than double what it earned in 2021. That is not slow, steady growth. That is a step change.
Gross margin tells a similarly strong story. Every dollar of revenue keeps more and more after paying for manufacturing. Gross margin rose from 74 percent in 2021 to 83 percent in 2025. That improvement came from a better product mix and lower production costs per unit. It means the business is not just getting bigger. It is getting more efficient as it grows.
Operating cash flow tells a more complicated story. It rose from $7.4 billion in 2021 to $16.8 billion in 2025, which sounds great. But free cash flow, which is what remains after spending on factories and equipment, stayed much lower. In 2023 free cash flow nearly disappeared, dropping to $0.8 billion. Capital spending on new manufacturing facilities has been enormous. The company spent $7.8 billion on capital expenditures in 2025 alone, compared with $5.1 billion in 2024. The business is generating cash faster than ever, but it is also pouring that cash back into building more capacity.
Net debt has climbed steadily alongside that spending. It stood at $13.1 billion in 2021 and reached $35.2 billion by 2025. The company is borrowing to build. That is a deliberate bet that future demand will fill the factories being built today.
The risk picture is unusually concentrated. Six products generated 82 percent of total revenues in 2025. Mounjaro and Zepbound alone accounted for 56 percent of total revenues that year. That means two medicines are carrying more than half the entire business. If anything goes wrong with either one, the financial impact would be immediate and large. The Trulicity patent, which covers another major diabetes medicine, is set to expire in the U.S. in 2027. When patents expire, generic competitors can enter quickly and prices tend to fall fast.
The U.S. government has added a new layer of pressure. A law called the Inflation Reduction Act lets Medicare set prices directly for certain medicines. Jardiance was selected first, with government-set prices starting in 2026. Trulicity and Verzenio were selected next, with prices set to take effect in 2028. The company has said it expects more of its products to be selected in future years. These price controls do not eliminate revenue, but they reduce how much the company earns per prescription on some of its most important medicines.
The supply chain carries its own risks. The company depends on China-based suppliers for critical ingredients. Geopolitical tensions, tariffs, or disruptions at those suppliers could cause shortages or delays. Pharmaceuticals are currently exempt from some tariffs, but that exemption could change. Building new manufacturing inside the U.S. and elsewhere takes years and billions of dollars, and there is no guarantee the new capacity will be finished on time or will meet actual demand.
An additional competitive threat comes from compounded versions of incretin medicines. Pharmacies that mix their own drug preparations have been producing versions of tirzepatide, the active ingredient in Mounjaro and Zepbound. The company has said these practices create patient safety risks and market confusion. The FDA confirmed in late 2024 that a shortage period had ended and that mass compounding should stop, but the company has said it cannot guarantee adequate regulation or compliance.