7 Companies Owned by Pfizer

Pharmaceuticals and Biopharmaceuticals

Pfizer Inc. (PFE) is a global biopharmaceutical company engaged in the discovery, development, manufacture, and sale of medicines and vaccines. Its business spans the following therapeutic areas: vaccines, oncology, internal medicine, hospital, inflammation and immunology, and rare disease.

Pfizer posted net income attributable to common shareholders of $22 billion on revenue of $81.3 billion in its 2021 fiscal year (FY), which ended Dec. 31, 2021. The company’s market capitalization was $279.3 billion as of Aug. 9, 2022.

Pfizer traces its origins to 1849, when Charles Pfizer and Charles Erhart founded Charles Pfizer & Co. in Brooklyn, New York. The company became a publicly traded company in 1942. In 1944, Pfizer succeeded in mass-producing penicillin, becoming the largest producer worldwide of the first antibiotic.

More recently, the company has been at the forefront of efforts to stem COVID-19. In August 2021 its COVID-19 vaccine was the first to receive full approval from the U.S. Food and Drug Administration (FDA), following emergency use authorization (EUA) from the agency in December 2020.

The vaccine, along with COVID-19 treatment Paxlovid, helped make Pfizer the world's top ranked drug company by revenue in 2021.

Acquisitions have fueled much of the company's growth over the past two decades. Pfizer acquired Warner-Lambert in 2000 to gain control of Lipitor, a blockbuster drug used to treat high cholesterol. Pharmaceutical companies spend significant amounts of money to develop new drugs. Once patented, these drugs may enable companies to reap outsized profits as an exclusive producer for years before competitors are allowed to develop and market generic alternatives.

Pfizer’s acquisition strategy in the early 2000s focused on companies with patented drugs. Its deal for Warner-Lambert and the ensuing buyout of Pharmacia in 2003 are two examples. But as healthcare costs continued to soar, the market for cheaper generic drugs showed strong potential for growth. As a result, Pfizer began targeting generic drugmakers with attractive drug pipelines, including Hospira in 2015. More recently, the company has been bolstering its pipeline of cancer treatments by acquiring several oncology-focused drug developers.

$5.4 billion

The total value of Pfizer's proposed acquisition of biopharmaceutical firm Global Blood Therapeutics (GBT), announced in August 2022. GBT is the developer of Oxbryta, an FDA-approved medicine for the treatment of sickle cell disease.

We look in detail at seven of Pfizer’s major acquisitions below.


  • Type of business: pharmaceuticals
  • Acquisition price: $116 billion (completed)
  • Acquisition date: June 20, 2000 (completed)

Warner-Lambert was formed in 1955 when William R. Warner & Co. combined with Lambert Pharmacal Co. The company subsequently expanded primarily through acquisitions—most notably the 1970 purchase of Parke-Davis, once the world’s largest drugmaker.

In 1996, Warner-Lambert and Pfizer entered into a co-marketing agreement for Lipitor, a synthetic lipid-lowering agent and the highest-selling drug in the world. Lipitor was Pfizer's principal motivation in its hostile takeover bid for Lipitor developer Warner-Lambert. Pfizer feared losing its marketing deal for Lipitor, under which it received half of the profits from sales of the drug. Warner-Lambert initially rejected the takeover bid, but after months of court battles agreed in February 2000 to be acquired by Pfizer. The deal closed in June 2000, making Pfizer the world’s second-largest and fastest-growing pharmaceutical company.


  • Type of business: pharmaceuticals
  • Acquisition price: $60 billion (completed)
  • Acquisition date: April 16, 2003 (completed)

Pharmacia was formed in April 2000 by the merger between Pharmacia & Upjohn and Monsanto and its pharmaceutical unit, Searle. At the time of the merger, Searle had an agreement with Pfizer to co-promote Celebrex, a blockbuster arthritis drug the companies developed together. Celebrex is a nonsteroidal anti-inflammatory drug used to temporarily relieve pain and inflammation.

Pharmacia completed the spinoff of its agricultural subsidiary Monsanto in August 2002. The month before, in July 2002, Pfizer agreed to purchase Pharmacia for $60 billion. The deal, finalized in April 2003, gave Pfizer full rights to Celebrex. It came during a time when pharmaceutical companies were struggling to develop new drugs, facing increasing competition from generic drugmakers, and pricing pressures from governments and private buyers. The acquisition made Pfizer the top pharmaceutical company by revenue in every major market in the world.


  • Type of business: pharmaceuticals
  • Acquisition price: $68 billion (completed)
  • Acquisition date: Oct. 15, 2009 (completed)

Wyeth started as John Wyeth and Brother, established in Philadelphia by John and Frank Wyeth in 1860. In the late 1960s the company's Ovral was the leading oral contraceptive in the United States. It has since been discontinued.

In January 2009 Pfizer agreed to purchase Wyeth in a deal valued at $68 billion. One motive was to soften the blow from the expected loss in revenue once the exclusivity period attached to the Lipitor patent ended.

Acquiring Wyeth also augmented Pfizer’s portfolio by adding two key drugs: Prevnar, a vaccine for infants against pneumococcal disease; and Enbrel, an arthritis drug. The company viewed vaccines and injectable biologic medicines as therapeutic areas less vulnerable to generic competition.

Pfizer completed the acquisition of Wyeth in October 2009 following approval by U.S. and Canadian antitrust regulators.


  • Type of business: pharmaceuticals and medical devices
  • Acquisition price: $16 billion (completed)
  • Acquisition date: Sept. 3, 2015 (completed)

Hospira became an independent, publicly traded company in 2004 after a spinoff from Abbott Laboratories (ABT). Over the next decade, the company became a leader in developing and manufacturing biosimilars, medicines functionally similar to more expensive biotech drugs.

Hospira’s biosimilars pipeline was key to Pfizer's 2015 bid to purchase the smaller rival. Pfizer had spent years focusing on acquiring companies that manufactured costly biotech drugs shielded by patents. Meanwhile, the new focus by governments and health insurers on curbing soaring medical costs was expected to fuel global demand for biosimilars. Hospira was also a leading provider of injectable drugs and infusion technologies.


  • Type of business: biopharmaceuticals
  • Acquisition price: $14.3 billion (completed)
  • Acquisition date: Sept. 28, 2016 (completed)

Medivation was founded in 2003 by David Hung, and went public through a reverse merger with a shell company in 2004. A reverse merger occurs when a private company purchases a publicly traded one and takes over its exchange listing.

Medivation specialized in developing cancer drugs. The big prize for Pfizer in acquiring the company in 2016 was Xtandi, a drug for treating prostate cancer. Xtandi was generating about $2 billion in annual sales for Medivation, and analysts were predicting that those sales could double.

Medivation also had other oncology treatments under development. Pfizer expected these to benefit from combination with its research efforts, helping the company to become a leader in oncology.

Array BioPharma

  • Type of business: biopharmaceuticals
  • Acquisition price: $11.2 billion (completed)
  • Acquisition date: July 30, 2019 (completed)

Array BioPharma, a company focused on the discovery and development of targeted small molecule drugs to treat patients with cancer and other diseases, was founded in 1998. The biopharmaceutical company first began collaborating with Pfizer in 2017 on developing cancer drugs.

Two years later, Pfizer paid a big premium to acquire Array BioPharma. The acquisition bolstered Pfizer’s expanding portfolio of cancer treatments with Braftovi and Mektovi. The drugs treat metastatic melanoma and other cancers.

Trillium Therapeutics

  • Type of business: biopharmaceuticals
  • Acquisition price: $2.2 billion (completed)
  • Acquisition date: Nov. 17, 2021 (completed)

Trillium Therapeutics, a clinical stage immuno-oncology company that develops therapies for the treatment of cancer, was launched in Canada in March 2004. In August 2021, Pfizer agreed to purchase Trillium at a 118% premium to the stock’s 60-day weighted average price. Pfizer closed the deal in November 2021.

Pfizer said that the deal bolstered its pipeline of cancer treatments. Trillium is currently developing two biologics, the molecules TTI-622 and TTI-621, to treat blood, bone marrow, and lymph node cancers.

Article Sources
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