Endo International plc

In 1920, Intravenous Products of America was incorporated as a privately owned pharmaceutical business operating in New York. By 1935 it had changed its name to Endo Products. The product line focused on medication for the treatment of pain (e.g. Percodan), a focus which continued during its acquisition by DuPont in 1969 (e.g. Percocet).

Endo Pharmaceuticals Holdings was created as a result of a $277 million management buyout of the division from DuPont Merck in 1997, led by Carol Ammon. Through the merger with Algos, it changed name again to Endo Pharmaceuticals Holdings Inc. and began trading as a public company.

In 2012, shareholders voted to again change the name to Endo Health Solutions, with Endo Pharmaceuticals becoming a segment of the business. Through the 2014 acquisition of Paladin Labs and subsequent corporate restructuring, Endo International plc was formed.

2022–2023 bankruptcy proceedings

In 2022, Endo's stock fell below $1 as the company faced restructuring of its $8 billion of debt.

On August 17, 2022 Endo International Plc filed for Chapter 11 bankruptcy protection after reaching a $6 billion deal with some of its creditors that related to opioid litigation in the US and a $6 billion deal with creditors, including for settling lawsuits.

The United States Department of Justice has objected to the plans, claiming they violate bankruptcy law.

Merger

In March 2025, Mallinckrodt and Endo announced plans to merge in a deal valued at $6.7 billion.

1999: Predecessor Endo Pharmaceuticals Holdings agreed to buy Algos Pharmaceutical Corporation, in a bid to gain additional products for the painkiller market.

2006: Endo acquired RxKinetix, leading to a fall in profits.

2009: Endo bought Indevus Pharmaceuticals to diversify into endocrinology and oncology. The company entered the male hypogonadism market later in 2010 with Fortesta 2% gel.

2010: Endo acquired generic manufacturer Qualitest Pharmaceuticals for $1.2 billion.

Lawsuits

Mesh

After facing lawsuits over its production of vaginal mesh implants, Endo shut down its production in 2016 to avoid further litigation It had set aside more than $2.6 billion to payments for such cases.

Opioids

Endo is one of the companies named in lawsuits by the states of Ohio, Missouri and Mississippi as responsible for the US opioid epidemic. Its 10-K statement indicates that a majority of the company's US revenue in 2016 was derived from the sale of prescription pain killers, predominantly opioids.

On June 8, 2017, the U.S. Food and Drug Administration (FDA) released a press statement in which it announced that it requested Endo to withdraw its opioid drug, oxymorphone hydrochloride (Opana ER), from the market. Opana has been linked to outbreaks of HIV, hepatitis C and serious blood disorders. It was the first time that the FDA had "taken steps to remove a currently marketed opioid pain medication from sale due to the public health consequences of abuse."

In 2021, New York Attorney General Letitia James filed a lawsuit against Endo and several other opioid manufacturers for their alleged contribution to the opioid epidemic in New York.

As part of Endo's 2022 bankruptcy proceedings, it agreed to spend more than $500 million settling opiod relating lawsuits. These proceedings now require Endo to turn over all court documents related to its role in the opioid crisis for publication in a public online archive.

In 2024, Endo agreed to a civil settlement of $464.9 million to resolve its civil liability under the federal False Claims Act by unlawfully promoting Opana ER, a dangerous opioid drug that was removed from the market by Endo at the FDA’s request.