A Legacy of Pharmaceutical Innovation
Founded in 1876 by Colonel Eli Lilly, a pharmaceutical chemist and Union army veteran, Eli Lilly and Company began with a focus on producing high-quality medicines. Headquartered in Indianapolis, Indiana, the company has grown into a global pharmaceutical leader.
Historical Milestones and Foundational Drugs
Eli Lilly has made significant contributions to public health throughout its history. A major achievement was the commercial mass production of insulin (Iletin) in 1923, a collaboration that transformed diabetes treatment. This established Lilly as a key research-based manufacturer.
Key historical achievements include:
- Penicillin: Lilly was involved in the mass production of penicillin during World War II.
- Polio Vaccine: In the 1950s, the company was a major producer of the Salk polio vaccine.
- Prozac (fluoxetine): Approved in 1987, this antidepressant became a significant drug for the company.
- Humulin: Introduced in 1982, Humulin was the first human insulin created using recombinant DNA technology.
Dominance in Modern Therapeutic Areas
Eli Lilly's current research focuses on diabetes, obesity, oncology, immunology, and neuroscience. Recent success is largely due to new drugs for diabetes and obesity.
The Rise of GLP-1 Agonists: Mounjaro and Zepbound
A primary driver of Lilly's recent growth is tirzepatide, marketed as Mounjaro for type 2 diabetes (approved May 2022) and Zepbound for obesity (approved November 2023). These drugs are effective for blood sugar control and weight loss, contributing significantly to Lilly's market value. In the first quarter of 2025, Mounjaro and Zepbound had combined revenues exceeding $6 billion. These drugs position Lilly as a major competitor to Novo Nordisk.
Comparison of Key Lilly Drugs
| Drug Name | Primary Indication | Mechanism of Action | Significance |
|---|---|---|---|
| Humalog (insulin lispro) | Diabetes | Rapid-acting insulin analog | A foundational modern insulin for mealtime blood sugar control. |
| Trulicity (dulaglutide) | Type 2 Diabetes | GLP-1 receptor agonist | A top-selling diabetes drug that helped establish Lilly's leadership in the GLP-1 class before Mounjaro. |
| Mounjaro (tirzepatide) | Type 2 Diabetes | Dual GIP and GLP-1 receptor agonist | A highly effective treatment for diabetes with significant weight loss benefits. |
| Zepbound (tirzepatide) | Chronic Weight Management | Dual GIP and GLP-1 receptor agonist | Approved specifically for obesity, representing a massive commercial opportunity and meeting a significant unmet medical need. |
| Verzenio (abemaciclib) | Oncology (Breast Cancer) | CDK4 & 6 inhibitor | A key product in Lilly's oncology portfolio, with over $1.16 billion in revenue in Q1 2025. |
| Prozac (fluoxetine) | Clinical Depression | Selective serotonin reuptake inhibitor (SSRI) | A historically significant drug that revolutionized depression treatment and became a cultural touchstone. |
Controversies and Challenges
Eli Lilly has faced controversies, notably regarding the pricing of insulin. The company faced accusations of inflating insulin prices, leading to public criticism and legal challenges. In response, Lilly announced a cap on out-of-pocket insulin costs at $35 per month for many patients in 2023.
In 2009, Lilly paid a $1.42 billion fine for the illegal marketing of its antipsychotic drug Zyprexa for unapproved uses.
The Future: A Robust Pipeline
Eli Lilly is actively investing in its research pipeline, particularly in new obesity treatments, including an oral GLP-1 pill. The company is also researching treatments for Alzheimer's disease and other conditions in neuroscience and immunology. Recent decisions include adjusting its R&D strategy based on clinical trial results.
Conclusion
From pioneering insulin and the polio vaccine to developing Prozac and its current leadership in diabetes and obesity with Mounjaro and Zepbound, Eli Lilly has a significant history in medicine. The company's high market value and pipeline indicate it will likely remain a major pharmaceutical force.
For more information on the company's history and products, one authoritative source is the Britannica entry on Eli Lilly and Company.
