Gilead Sciences

The company was formed in 1987 as Oligogen; its later name was inspired by the “balm of Gilead,” an ancient medicine referenced in the Bible.⁠[1]

It held its IPO in 1992. Its first drug, Vistide, for cytomegalovirus retinitis in AIDS patients, was approved in 1996. It acquired NeXstar Pharmaceuticals, maker of AmBisome, in 1999 and first turned a profit in 2001.⁠[1]

On June 23, 2004, Gilead announced that Standard & Poor’s would add the company to the S&P 500S&P 500The S&P 500 is a U.S. large-cap equity index compiled by S&P Dow Jones Indices. It includes 500 leading companies, covers about 80% of available market capitalization and is described by S&P DJI as “widely regarded as the best single gauge of large-cap U.S. equities.”Open the full entry and its GICS Biotechnology Sub-Industry Index at the close of trading on June 30, 2004.⁠[2]

Gilead completed its acquisition of Pharmasset, Inc. for $137 per share in cash, about $11.2 billion in aggregate, and Pharmasset became a wholly owned subsidiary.⁠[3]

In 2014, Gilead Sciences established a branch in Hong Kong; its Hong Kong site also serves Macau and Singapore.⁠[4]

A bipartisan 18-month investigation led by Senators Ron Wyden and Chuck Grassley found that Gilead priced the hepatitis C drug Sovaldi at $1,000 per pill, or $84,000 per course, to maximize revenue, and launched its successor Harvoni at $94,500.⁠[5]

In January 2016, Gilead announced that chief operating officer John Milligan would become CEO on March 10, while John Martin, CEO since 1996, would become executive chairman. Both joined Gilead in 1990.⁠[6]

Gilead completed its acquisition of Kite Pharma, Inc., based in Santa Monica, California, for $180 per share in cash, about $11.9 billion in aggregate. Kite’s lead product candidate, axi-cel, targets relapsed or refractory aggressive non-Hodgkin lymphoma.⁠[7]

On December 10, 2018, Gilead named Daniel O’Day, CEO of Roche Pharmaceuticals since 2012, as chairman and CEO effective March 1, 2019. Milligan stepped down at the end of 2018, Gregg Alton served as interim CEO from January 1 to March 1, 2019, and chairman John Martin left the board on March 1.⁠[8]

Gilead completed its acquisition of Immunomedics, Inc. at $88.00 per share in cash, about $21 billion in aggregate. Immunomedics’ Trodelvy was the first FDA-approved anti-Trop-2 antibody-drug conjugate. Immunomedics shares ceased trading on the Nasdaq Global Market.⁠[9]

Between September 2022 and October 2025, Gilead settled or reached agreements with generic manufacturers over U.S. patents for Descovy, Vemlidy, Odefsey, Genvoya and Biktarvy. Under the Biktarvy settlements, no U.S. generic Biktarvy tablets are expected before April 1, 2036.⁠[10]

Total 2025 revenues rose 2% to $29.4 billion; net income was $8.51 billion and diluted EPS $6.78, versus $0.38 in 2024. HIV product sales rose 6% to $20.8 billion, including $14.3 billion from Biktarvy. O’Day called Yeztugo “the world’s first twice-yearly HIV prevention therapy.”⁠[11]

In 2025 the FDA approved Yeztugo for HIV pre-exposure prophylaxis. As of December 31, 2025, Gilead had approximately 17,000 employees.⁠[12]

In 2026, Gilead announced acquisitions of Arcellx, Tubulis and Ouro Medicines and recognized acquired in-process R&D expenses for them; it also signed a definitive agreement to acquire PepStar Therapeutics Limited, pending as of October 29. Third-quarter revenues rose 7% to $8.3 billion. CMS has set Biktarvy’s “Maximum Fair Price,” effective January 1, 2028.⁠[13]

For the first nine months of 2026, revenues were $23.06 billion and the net loss was $6.05 billion, compared with net income of $6.33 billion a year earlier. Cash paid for acquisitions was $11.34 billion, and acquired in-process R&D expenses were $12.17 billion.⁠[14]