History of Pfizer in Timeline

By Popular Timelines Editorial Team · Updated: July 12, 2026

Pfizer Inc. is a leading global pharmaceutical corporation headquartered in New York City. Founded in 1849, the company focuses on the discovery, development, and manufacturing of healthcare products, including medicines and vaccines across various therapeutic areas such as oncology, immunology, cardiology, and infectious diseases. Pfizer is widely recognized for its significant contributions to global health, most notably its rapid development of the Comirnaty COVID-19 vaccine in partnership with BioNTech. The company operates through an extensive research and development pipeline, leveraging cutting-edge biotechnology and mRNA platforms to address unmet medical needs. Through its commitment to innovation, Pfizer remains a cornerstone of the global healthcare industry, continuously striving to bring breakthrough therapies to patients worldwide while maintaining a heavy emphasis on clinical research, manufacturing excellence, and strategic global partnerships.

1906: Pfizer Annual Sales Milestone

In 1906, Pfizer achieved a significant financial milestone as the company's annual sales figures surpassed the $3 million mark.

1919: Commercialization of Fungus-Based Citric Acid Production

In 1919, following a supply disruption of imported calcium citrate during World War I, Pfizer successfully commercialized a new method of producing citric acid by using a specific fungus to ferment sugar.

June 2, 1942: Pfizer Incorporation

On June 2, 1942, Pfizer officially incorporated its business operations under the legal framework of the Delaware General Corporation Law.

1950: Discovery of Oxytetracycline

In 1950, Pfizer discovered the antibiotic oxytetracycline, a breakthrough that successfully transformed the organization from a fine chemicals manufacturer into a research-driven pharmaceutical enterprise.

1959: Establishment of Animal Health Division

During 1959, Pfizer expanded its operational scope by launching an animal health division, supported by the construction of a 700-acre research facility and farm located in Terre Haute, Indiana.

1960: Relocation of medical research facilities

In 1960, Pfizer shifted its primary medical research laboratory operations from their long-standing location in New York City to a brand-new facility situated in Groton, Connecticut.

1965: John Powers, Jr. Appointed CEO

In 1965, John Powers, Jr. took over the role of chief executive officer at Pfizer, marking a leadership transition as he succeeded the outgoing CEO, John McKeen.

1972: Edmund T. Pratt Jr. Appointed CEO

In 1972, Edmund T. Pratt Jr. assumed the role of Chief Executive Officer at Pfizer, taking over the leadership position from John Powers, Jr.

1980: Launch of Feldene

In 1980, Pfizer introduced Feldene (piroxicam), an anti-inflammatory drug, which made history by becoming the company's first pharmaceutical product to generate $1 billion in global revenue.

1981: FDA Approval of Diflucan

In 1981, Pfizer received official approval for Diflucan (fluconazole), marking a significant medical milestone as the first oral medication designed to treat a wide array of severe fungal infections, such as candidiasis and cryptococcosis.

1986: Acquisition of Zithromax Rights

In 1986, Pfizer secured the global rights to the macrolide antibiotic Zithromax (azithromycin) from the pharmaceutical company Pliva, which later became a standard first-line treatment for community-acquired pneumonia.

1989: Creation of Viagra

In 1989, Pfizer scientists Peter Dunn and Albert Wood developed sildenafil, later known as Viagra, intending it to serve as a treatment for angina and high blood pressure.

1991: Marketing Launch of Zoloft

In 1991, Pfizer initiated the marketing of Zoloft (sertraline), an antidepressant drug in the SSRI class that was originally synthesized by company chemists nine years prior.

1991: William C. Steere, Jr. appointed as CEO of Pfizer

In 1991, William C. Steere, Jr. assumed the role of Chief Executive Officer at Pfizer, taking over the position from his predecessor, Edmund T. Pratt Jr.

1991: UK Patent Granted

In 1991, the medication sildenafil was officially patented within the United Kingdom for its intended use as a treatment for heart-related conditions.

1996: FDA Approval of Aricept and Norvasc

In 1996, the Food and Drug Administration granted approval for two significant medications: Aricept (donepezil), developed in partnership with Eisai for the treatment of Alzheimer's disease, and Norvasc (amlodipine), a calcium channel blocker used to treat hypertension.

1996: US Patent Granted

The drug sildenafil received an official patent in the United States in 1996, following clinical trials that revealed its unexpected effects on patients.

1997: Co-marketing agreement for Lipitor

In 1997, Pfizer established a co-marketing partnership with Warner–Lambert regarding the distribution and promotion of Lipitor (atorvastatin), a pharmaceutical treatment for hypercholesterolemia that demonstrated superior efficacy in LDL-C reduction compared to existing statins.

March 1998: FDA Approval

In March 1998, the United States Food and Drug Administration granted official approval for the use of Viagra.

December 1998: Bob Dole Named Spokesperson

In December 1998, Pfizer officially engaged Bob Dole to serve as the public spokesperson for Viagra.

June 2000: Pfizer Acquires Warner-Lambert

In June 2000, Pfizer completed the acquisition of Warner-Lambert for $116 billion, a move that established the company as the second-largest pharmaceutical firm in the world at the time. As a result of this merger, Pfizer was required by the Federal Trade Commission to divest certain assets, such as the lice treatment product RID and the antidepressant Celexa, to resolve antitrust concerns.

2000: Forbes Global 2000 Ranking

In 2000, Pfizer secured the 73rd position on the Forbes Global 2000 list, reflecting its significant financial standing and market influence during that year.

2001: Henry McKinnell Appointed CEO

In 2001, Henry McKinnell assumed the role of CEO at Pfizer, succeeding the outgoing leader William C. Steere, Jr.

2002: Bill & Melinda Gates Foundation Stock Purchase

In 2002, the Bill & Melinda Gates Foundation made a strategic financial move by purchasing stock in the pharmaceutical company Pfizer.

2003: Pfizer and Pharmacia Merger

In 2003, Pfizer completed a merger with Pharmacia, resulting in the acquisition of Searle and SUGEN. During this same year, Pfizer made the decision to close the SUGEN facility, leading to the layoff of over 300 employees and the transition of various research programs to Pfizer's internal operations.

2004: FDA Approval of Lyrica

In 2004, Pfizer received official approval for Lyrica (pregabalin), a versatile medication designed to address epilepsy, neuropathic pain, fibromyalgia, restless leg syndrome, and generalized anxiety disorder.

2005: Peak Commercial Success of Zoloft

During 2005, the final full year before the drug faced generic competition, Zoloft generated more than $3 billion in sales and had been utilized to treat over 100 million patients.

January 2006: FDA Approval of Sunitinib

In January 2006, the cancer medication Sunitinib, which originated from a program developed by SUGEN prior to its acquisition by Pfizer, received official approval from the FDA for human use.

July 2006: Jeff Kindler Appointed CEO

In July 2006, Jeff Kindler officially succeeded Henry McKinnell as the Chief Executive Officer of Pfizer, marking a significant leadership transition for the pharmaceutical company.

October 2006: Acquisition of PowerMed

In October 2006, Pfizer officially announced its intent to acquire PowerMed, a strategic move to bolster its capabilities and market presence.

December 3, 2006: Termination of torcetrapib clinical development

On December 3, 2006, Pfizer officially halted the development of the drug torcetrapib after a Phase III clinical trial revealed a higher mortality rate among patients taking the drug in combination with Lipitor compared to those taking Lipitor alone. The trial, involving 15,000 participants, showed an unexpected increase in patient deaths, leading to a $1 billion loss and an 11% decline in Pfizer's stock price.

2006: Patent Expiration for Zoloft

The patent protection for the antidepressant Zoloft expired in the summer of 2006, paving the way for the introduction of generic versions of the medication.

2007: Initiation of Anti-Counterfeiting Legal Strategy

Starting in 2007, Pfizer began a concentrated period of legal investment and civil litigation against counterfeit drug manufacturers to protect their brand and recover losses. By the end of this period, the company had successfully invested millions in investigations and legal fees to secure millions more in recoveries.

July 2008: Job Reductions at Portage Manufacturing Facility

In July 2008, Pfizer announced the elimination of 275 positions at its manufacturing plant located in Portage, Michigan. This site, which was the historical headquarters for the Upjohn Company, came under Pfizer's ownership following their acquisition of Pharmacia.

2009: Closure of the Brooklyn Plant

In 2009, Pfizer officially ceased operations at its long-standing manufacturing plant located in Brooklyn, New York, marking the end of the facility's extensive history in the region.

2010: Conclusion of Counterfeit Recovery Efforts

By 2010, Pfizer had completed a multi-year effort involving the hiring of international experts to combat counterfeit prescription drugs, resulting in $5.1 million in recovered funds and an additional $5 million in pending civil lawsuit claims.

2011: Lipitor patent expiration and sales milestone

By the time its patent expired in 2011, Lipitor had become the best-selling pharmaceutical in history, having generated approximately $125 billion in total revenue over its 14.5-year market presence.

2014: Upholding of Lyrica Patent

During 2014, the United States patent for Lyrica was successfully defended against challenges from generic manufacturers, which resulted in the patent expiration date being pushed to 2018.

2018: Extended Patent Expiration

Following the legal victory in 2014, the extended expiration date for the United States patent on the medication Lyrica arrived in 2018.

2020: Patent Expiration

The legal patent protections for Viagra officially expired in 2020.

2025: Pfizer 2025 Financial Performance and Product Revenue

In 2025, Pfizer generated significant revenue from its portfolio of medications and vaccines, with 59% of its total revenue originating from the United States, 5% from China, and 36% from international markets. Major contributors to these revenues included Eliquis, Prevnar, Paxlovid, Vyndaqel, Comirnaty, and Ibrance.