Eli Lilly reported strong Q4 2025 growth driven by rising demand for Mounjaro and Zepbound, highlighting the expanding clinical impact of tirzepatide therapies in diabetes and obesity.
Written By: Sana Khan BPharm
Reviewed By: Pharmacally Editorial Team
U.S.-based biopharmaceutical major Eli Lilly reported strong fourth-quarter 2025 performance, largely driven by rising global demand for its tirzepatide therapies, Mounjaro for type 2 diabetes and Zepbound for obesity. The quarter highlighted how sustained clinical adoption of metabolic therapies translated into robust revenue growth, supported by expanded access and broadening patient uptake.
Topline Performance Reflects Clinical Demand
Lilly’s worldwide revenue increased 43% year over year to $19.3 billion in the fourth quarter of 2025. The growth was primarily volume-driven, with prescription volumes rising 46%, while a 5% decline in realized prices modestly offset gains. Reported earnings per share increased by more than 50%, reflecting operating leverage from higher sales volumes.
Tirzepatide therapies accounted for the majority of this momentum:
- Mounjaro recorded $7.4 billion in quarterly sales, representing 110% growth compared with Q4 2024.
- Zepbound generated $4.2 billion, up 123% year over year.
Together, these therapies formed the core driver of Lilly’s quarterly growth, underscoring their central role in the company’s current performance.
How Tirzepatide Therapies Work
Mounjaro and Zepbound are both based on tirzepatide, a dual incretin receptor agonist that targets both glucose regulation and appetite control. By stimulating insulin secretion and reducing caloric intake, tirzepatide has demonstrated superior reductions in blood glucose and body weight compared with several earlier GLP-1 receptor agonists in clinical trials.
This dual mechanism makes tirzepatide particularly effective for patients with overlapping metabolic conditions. The strong real-world uptake seen in 2025 reflects increasing clinician confidence in therapies that address both type 2 diabetes and obesity simultaneously.
Volume Growth Despite Pricing Pressure
The 46% increase in prescription volume points to expanding access through broader insurance coverage and formulary inclusion. Although net pricing declined in certain markets, the scale of volume growth outweighed these pressures, resulting in strong net sales expansion.
The United States remained the largest contributor, while international markets also supported growth through new launches and improved reimbursement pathways, reinforcing tirzepatide’s global commercial footprint.
Sustained Momentum Versus Prior Year
In the fourth quarter of 2024, Lilly reported revenue of $13.5 billion, with early traction from tirzepatide therapies already evident. The 2025 results confirm that this momentum has not only continued but strengthened, with Mounjaro and Zepbound now firmly established as core revenue pillars rather than emerging assets.
Despite increasing competition in the metabolic space, including alternative GLP-1-based approaches, Lilly’s tirzepatide portfolio maintained strong demand throughout the year.
Contribution From the Broader Portfolio
Other therapeutic areas continued to support overall growth, though at a more moderate pace than tirzepatide. Oncology, immunology, neuroscience, and legacy diabetes products provided steady contributions, reinforcing portfolio stability. However, none matched the scale or growth rate of Mounjaro and Zepbound, which clearly dominated the quarter’s performance.
This clinical and commercial momentum in 2025 helped position Eli Lilly as the first pharmaceutical and biotechnology company to achieve a $1 trillion valuation, highlighting the scale of impact generated by advances in metabolic disease care. As global access expands and long-term outcomes data continue to mature, Mounjaro and Zepbound are expected to remain central to Lilly’s therapeutic strategy and long-term growth trajectory.
References
Lilly reports fourth-quarter 2025 financial results and provides 2026 guidance, 04 February 2026, Lilly reports fourth-quarter 2025 financial results and provides 2026 guidance | Eli Lilly and Company