Eli Lilly has seized leadership in the GLP-1 market with tirzepatide-based Mounjaro and Zepbound, driving explosive revenue growth and capturing over 60% U.S. market share. Recent results show combined tirzepatide sales exceeding $36 billion in 2025, with Q4 alone topping $11 billion amid triple-digit gains. The company guides $80-83 billion in 2026 revenue, fueled by volume momentum, upcoming oral orforglipron launch, and a robust pipeline including retatrutide. While pricing pressures exist, expanded access via government agreements and next-generation therapies could sustain long-term dominance in a market projected to approach $100 billion by decade’s end, potentially delivering substantial shareholder returns over decades.
Eli Lilly’s GLP-1 Empire: From Boom to Enduring Growth Engine
Eli Lilly has transformed the obesity treatment landscape through its incretin-based therapies, particularly tirzepatide, marketed as Mounjaro for type 2 diabetes and Zepbound for chronic weight management. The company’s strategic focus on superior efficacy—demonstrated by greater average weight loss compared to competitors—has propelled it from challenger to clear market leader in the U.S.
In the latest reported quarter (Q4 2025), worldwide revenue reached $19.3 billion, up 43% year-over-year, primarily driven by volume surges in Mounjaro and Zepbound. Mounjaro generated $7.4 billion (110% growth), while Zepbound contributed $4.3 billion (123% growth), combining for over $11.7 billion in the period. For the full year 2025, these two products alone delivered approximately $36.5 billion in sales, representing more than half of the company’s total revenue of $65.2 billion (45% annual growth).
This performance reflects Lilly’s commanding position, with U.S. incretin analogs market share climbing to 60.5% in the final weeks of 2025, up from prior periods. The shift has come at the expense of the previous pioneer, as Lilly’s dual GIP/GLP-1 mechanism has consistently shown stronger clinical outcomes in head-to-head comparisons.
2026 Outlook: Ambitious Guidance Amid Evolving Dynamics
Lilly’s forward-looking guidance underscores confidence in sustained momentum. The company projects 2026 revenue between $80 billion and $83 billion, surpassing analyst expectations centered around $77-78 billion. Non-GAAP earnings per share are anticipated in the $33.50 to $35.00 range, reflecting robust operating leverage despite investments in manufacturing expansion and R&D.
Key drivers include continued tirzepatide uptake worldwide, expanded access channels, and diversification within the incretin class. Pricing headwinds are acknowledged, including mid-teens global declines from access agreements, direct-to-patient initiatives, and reimbursement changes. However, volume growth—bolstered by resolved supply constraints and new pathways like Medicare coverage—is expected to more than offset these pressures.
Pipeline Strength: Next-Generation Innovations to Extend the Runway
Beyond current blockbusters, Lilly’s obesity franchise extends into oral and multi-agonist therapies designed to improve convenience, tolerability, and outcomes.
Orforglipron, an oral small-molecule GLP-1 receptor agonist, represents a major advancement. Regulatory submissions are underway in key markets, with U.S. approval anticipated in the second quarter of 2026 under a priority review. Unlike peptide-based orals requiring strict administration conditions, orforglipron offers straightforward dosing. Phase 3 data demonstrated strong weight maintenance in patients transitioning from injectables, positioning it to capture patients seeking pill convenience and potentially broaden the market to those deterred by needles.
Further out, retatrutide—a triple agonist targeting GLP-1, GIP, and glucagon—has delivered impressive Phase 3 results. In patients with obesity and knee osteoarthritis, the highest dose achieved up to 28.7% average weight loss (71 pounds) alongside substantial pain reduction (over 74%). Additional trials explore applications in metabolic dysfunction-associated steatohepatitis (MASH), obstructive sleep apnea, and other comorbidities. Regulatory submissions could follow in 2026-2027, potentially setting a new efficacy benchmark.
These candidates build on tirzepatide’s foundation, with patent protection extending into the late 2030s in major markets, providing a long runway for exclusivity and revenue compounding.
Market Opportunity: A Multi-Decade Horizon
The obesity pharmacotherapy sector is evolving from a niche diabetes adjunct to a cornerstone chronic disease treatment. Current estimates place the global market approaching $100 billion by 2030, with some forecasts extending higher by the mid-2030s as penetration increases among the hundreds of millions affected by obesity and related conditions.
Lilly’s advantages include manufacturing scale expansions (new facilities in the U.S. and Europe), direct-to-consumer platforms like LillyDirect, and partnerships enhancing access. As the market matures, focus shifts from acute shortages to sustained therapy, where superior efficacy, tolerability, and convenience will drive loyalty and share gains.
Risks and Resilience Factors
Competition remains fierce, with emerging orals and compounded alternatives pressuring pricing. Regulatory and reimbursement shifts could introduce volatility. Yet Lilly’s track record of execution—rapid supply ramp-up, pipeline successes, and proactive access strategies—positions it to navigate these challenges effectively.
The GLP-1 revolution, once viewed as a short-term surge, now appears poised for decades of expansion as obesity is increasingly treated as a chronic medical condition. Lilly’s leadership, backed by differentiated science and commercial agility, offers a compelling case for long-term value creation.
Disclaimer: This article is for informational purposes only and does not constitute investment advice, financial recommendations, or endorsements of any security. Market conditions can change rapidly; investors should conduct their own due diligence and consult professionals.