REGENERON PHARMACEUTICALS, INC.

The company was founded by CEO Leonard Schleifer and scientist George Yancopoulos in 1988.

Regeneron has developed aflibercept, a VEGF inhibitor, and rilonacept, an interleukin-1 blocker. VEGF is a protein that normally stimulates the growth of blood vessels, and interleukin-1 is a protein that is normally involved in inflammation. [ citation needed ]

On March 26, 2012, Bloomberg announced that Sanofi and Regeneron were in development of a new drug that would help reduce cholesterol up to 72% more than its competitors. The new drug would target the PCSK9 gene.

In July 2015, the company announced a new global collaboration with Sanofi to discover, develop, and commercialize new immuno-oncology drugs, which could generate more than $2 billion for Regeneron, with $640 million upfront, $750 million for proof-of-concept data, and $650 million from the development of REGN2810. REGN2810 was later named cemiplimab. In 2019, Regeneron Pharmaceuticals was announced the 7th best publicly listed company of the 2010s, with a total return of 1,457%. Regeneron Pharmaceuticals was home to the two highest-paid pharmaceutical executives as of 2020.

In October 2017, Regeneron made a deal with the Biomedical Advanced Research and Development Authority (BARDA) that the U.S. government would fund 80% of the costs for Regeneron to develop and manufacture antibody-based medications, which subsequently, in 2020, included their COVID-19 treatments, and Regeneron would retain the right to set prices and control production. This deal was criticized in The New York Times. Such deals are not unusual for routine drug development in the American pharmaceutical market.

In 2019, the company was added to the Dow Jones Sustainability World Index.

In May 2020, Regeneron announced it would repurchase approx. 19.2 million of its shares for around $5 billion, held directly by Sanofi. Prior to the transaction, Sanofi held 23.2 million Regeneron shares.

In August 2023, Regeneron announced it would acquire Decibel Therapeutics.

In May 2025, the company was awarded $135.6 million in compensatory damages and $271.2 million in punitive damages in the United States District Court for the District of Delaware in a victorious antitrust case filed against Amgen. Regeneron alleged Amgen employed anticompetitive practices to exclude Praluent from the market and elevate Amgen's rival Repatha.