Direct Answer
Amgen was founded on April 8, 1980, in Thousand Oaks, California, under the name Applied Molecular Genetics Inc. George Rathmann served as the founding CEO. The company shortened its name to Amgen and completed its Nasdaq IPO in 1983. Epogen (epoetin alfa), FDA-approved in 1989 to treat anemia in dialysis patients, became one of the best-selling biotechnology drugs in history and established Amgen as the first large, independent biotech company. Amgen joined the Dow Jones Industrial Average on August 31, 2020. In October 2023, Amgen closed its acquisition of Horizon Therapeutics for approximately $27.8 billion, the largest biotech acquisition at the time.
Origins
Amgen traces its origins to a meeting of venture capitalists and scientists organized by William Bowes in 1980. The founding group, which included George Rathmann as CEO and several scientists, incorporated the company on April 8, 1980, in Thousand Oaks, California, under the name Applied Molecular Genetics Inc. The location in Ventura County, outside Los Angeles, reflected a deliberate choice to be near the emerging California biotech ecosystem while retaining space to build its own manufacturing facilities.
Rathmann, who had worked at Abbott Laboratories before joining Amgen, brought both scientific and business experience to a field that was then new enough that no established model existed for commercializing recombinant DNA technology. Amgen's early research program was broad, exploring potential products across multiple therapeutic areas, and the company came close to failing before its first major product candidates showed commercial potential.
Key milestones
| Date | Event |
|---|---|
| April 8, 1980 | Applied Molecular Genetics Inc. incorporated in Thousand Oaks, California; George Rathmann named founding CEO |
| 1983 | Amgen IPO on Nasdaq; company name shortened from Applied Molecular Genetics Inc. to Amgen |
| 1989 | Epogen (epoetin alfa) approved by the FDA to treat anemia in dialysis patients; becomes one of the best-selling biotech drugs in history |
| 1991 | Neupogen (filgrastim) approved by the FDA to treat neutropenia caused by chemotherapy |
| 1994 | Amgen acquires Synergen |
| 1998 | Enbrel (etanercept) developed through joint venture with Wyeth; treats rheumatoid arthritis; one of the first anti-TNF biologics approved |
| 2002 | Aranesp (darbepoetin alfa) approved by the FDA; long-acting version of Epogen for anemia treatment |
| 2002 to 2012 | ESA controversy: FDA adds black box warnings to Epogen and Aranesp after studies show increased cardiovascular risk and shortened survival in certain cancer patients; Medicare restricts use; revenues decline |
| 2006 | Amgen acquires full U.S. and Canadian Enbrel rights from Wyeth, becoming sole marketer in those markets |
| 2012 | Robert Bradway becomes CEO; Prolia (denosumab) grows into a major revenue driver; XGEVA (denosumab) approved for bone metastases prevention |
| 2013 | Amgen acquires Onyx Pharmaceuticals for approximately $10.4 billion, adding Kyprolis (carfilzomib) for multiple myeloma |
| 2015 | Repatha (evolocumab), a PCSK9 inhibitor that significantly lowers LDL cholesterol, approved by the FDA; Amgen enters the biosimilars market |
| 2019 | Amgen acquires Otezla (apremilast) from Celgene for approximately $13.4 billion; Otezla is an oral treatment for psoriasis and psoriatic arthritis |
| August 31, 2020 | Amgen added to the Dow Jones Industrial Average, replacing Pfizer |
| 2021 | Lumakras (sotorasib) approved by the FDA as the first KRAS G12C inhibitor; treats non-small cell lung cancer with the KRAS G12C mutation, a target considered undruggable for approximately 40 years |
| 2023 | Amjevita (adalimumab-atto), Amgen's biosimilar of Humira (adalimumab), launched in the United States |
| October 2023 | Amgen closes acquisition of Horizon Therapeutics for approximately $27.8 billion; adds Tepezza (teprotumumab) for thyroid eye disease, KRYSTEXXA (pegloticase) for gout, and Uplizna (inebilizumab) for neuromyelitis optica |
| 2024 | MariTide (maridebart cafraglutide, AMG 133) Phase 2 results show significant weight loss, positioning Amgen as a competitor in the GLP-1 receptor agonist obesity treatment market |
CEO timeline
| CEO | Tenure |
|---|---|
| George Rathmann | 1980 to 1988 (co-founder) |
| Gordon Binder | 1988 to 2000 |
| Kevin Sharer | 2000 to 2012 |
| Robert Bradway | 2012 to present |
Four eras of Amgen history
Founding and early biotech era (1980 to 1995)
Amgen's earliest years were characterized by financial precarity and a broad, exploratory research program typical of first-generation biotech companies. The company's 1983 Nasdaq IPO raised capital that kept research running through a period when no product was near approval. The key discovery came through Amgen scientist Fu-Kuen Lin, who cloned the gene for erythropoietin in 1983, providing the scientific basis for Epogen. FDA approval in 1989 transformed Amgen almost immediately: Epogen generated hundreds of millions of dollars in its first years on the market, treating anemia in dialysis patients who previously had limited options. Neupogen, approved in 1991, provided a second blockbuster product and demonstrated that Amgen's recombinant protein platform could produce multiple commercial successes. By the mid-1990s, Amgen had become the largest independent biotechnology company in the United States by revenue, a position it has maintained since.
Enbrel, acquisitions, and portfolio expansion (1995 to 2010)
The partnership with Wyeth to develop and commercialize Enbrel (etanercept), a TNF blocker for rheumatoid arthritis, extended Amgen's reach into immunology beyond its core hematology franchise. Enbrel became one of the world's best-selling drugs. The 2006 buyout of Wyeth's stake in U.S. and Canadian Enbrel rights gave Amgen full control of those revenues. During the same period, Aranesp (darbepoetin alfa), a longer-acting version of Epogen, expanded the erythropoiesis-stimulating agent (ESA) franchise, and annual revenues across both products reached several billion dollars. However, clinical trial results in the 2000s showed that high hemoglobin targets enabled by Epogen and Aranesp in certain cancer patients were associated with increased cardiovascular risk and reduced survival in some settings, triggering a series of FDA label changes, black box warnings, and Medicare coverage restrictions that significantly reduced ESA revenues.
Post-ESA diversification and pipeline investment (2010 to 2019)
Robert Bradway became CEO in 2012 and pursued a strategy of diversifying Amgen's revenue base through both internal pipeline development and acquisitions. Prolia (denosumab) and XGEVA (denosumab) addressed bone loss in postmenopausal women and bone metastases prevention in cancer patients, respectively, and together grew into multi-billion dollar annual revenue contributors. The $10.4 billion acquisition of Onyx Pharmaceuticals in 2013 added Kyprolis (carfilzomib) for relapsed or refractory multiple myeloma. Repatha (evolocumab), a PCSK9 inhibitor approved in 2015, represented a potential breakthrough in LDL cholesterol reduction for patients with cardiovascular disease. Amgen also entered the biosimilars market in 2015, applying its expertise in manufacturing complex biological molecules to make copies of competitors' blockbuster biologics. The $13.4 billion acquisition of Otezla from Celgene in 2019, required as a condition of Celgene's merger with Bristol-Myers Squibb, added an oral treatment for psoriasis and psoriatic arthritis that broadened Amgen's immunology portfolio beyond injectables.
Horizon acquisition, biosimilars, and the obesity market (2019 to present)
Amgen's 2021 FDA approval of Lumakras (sotorasib) for non-small cell lung cancer with the KRAS G12C mutation was a significant scientific achievement: KRAS had been considered an undruggable oncology target for approximately four decades because the protein's structure made small-molecule inhibition appear impractical. Lumakras was the first approved therapy to directly target KRAS. The October 2023 close of the Horizon Therapeutics acquisition for approximately $27.8 billion was the largest transaction in Amgen's history and one of the largest in biotech at that time. The deal added Tepezza for thyroid eye disease, KRYSTEXXA for refractory gout, and Uplizna for neuromyelitis optica spectrum disorder, strengthening Amgen's position in rare diseases with limited competition. On the biosimilars side, the 2023 U.S. launch of Amjevita, a biosimilar of AbbVie's Humira (adalimumab), one of the world's best-selling drugs, put Amgen directly in the market for immunology biosimilars. Phase 2 data for MariTide (maridebart cafraglutide) released in 2024 showed meaningful weight loss, entering Amgen into the GLP-1 receptor agonist obesity space alongside Novo Nordisk and Eli Lilly.
Frequently Asked Questions
When was Amgen founded?
Amgen was founded on April 8, 1980, in Thousand Oaks, California, under the name Applied Molecular Genetics Inc. George Rathmann, a chemist and executive who had previously worked at Abbott Laboratories, served as the founding CEO. The company shortened its name to Amgen and went public on Nasdaq in 1983.
What was Amgen's first major product?
Amgen's first major product was Epogen (epoetin alfa), an erythropoiesis-stimulating agent approved by the FDA in 1989 to treat anemia in dialysis patients. Epogen became one of the best-selling biotechnology drugs in history, generating billions of dollars in annual revenue and establishing Amgen as the first large, independent biotech company. A second major product, Neupogen (filgrastim), was approved in 1991 to treat neutropenia caused by chemotherapy.
When did Amgen join the Dow Jones Industrial Average?
Amgen joined the Dow Jones Industrial Average on August 31, 2020, replacing Pfizer. The addition reflected the growing importance of biotechnology in the U.S. economy and made Amgen one of the few biotech companies in the 30-stock index.
What was the Horizon Therapeutics acquisition?
Amgen completed the acquisition of Horizon Therapeutics in October 2023 for approximately $27.8 billion, making it the largest biotech acquisition at the time. The deal added Tepezza (teprotumumab) for thyroid eye disease, KRYSTEXXA (pegloticase) for gout, and Uplizna (inebilizumab) for neuromyelitis optica spectrum disorder to Amgen's portfolio. Horizon's drugs addressed rare diseases with limited treatment alternatives and fitted Amgen's strategy of expanding beyond its core red blood cell and white blood cell drug franchises.