Purdue Pharma’s bankruptcy filing this week punctuates a fall from its perch as one of the pharmaceutical industry’s most recognizable marketers of opioid pain pills. At its height, Purdue’s signature OxyContin product notched billions of dollars in annual sales, fueled in part by booming demand for high-dose pills.

Purdue made about 10% of pills containing oxycodone — the active ingredient in OxyContin — that were purchased by U.S. pharmacies from 2006 to 2012, according to a Wall Street Journal analysis of opioid sales data maintained by the Drug Enforcement Administration. But when taking into account the dosage strength of each pill, OxyContin represented a market-leading 27% of oxycodone sold during the seven-year period reviewed by the Journal.

High-dose pills are more prone to abuse, according to physicians and public-health and law-enforcement officials. The sales data were obtained by plaintiffs’ attorneys representing municipalities in cases against Purdue and other pharmaceutical-supply-chain players for their alleged roles in the opioid crisis, and made public as the result of a lawsuit brought by The Washington Post and HD Media. The Journal obtained the data from the plaintiffs’ attorneys. Sales data for other years hasn’t been made public.

In a statement, Purdue said hydrocodone, another prescription opioid, should have been included in the Journal’s analysis because it is widely prescribed and has been linked to abuse. Purdue didn’t make any hydrocodone-based products during the period reviewed by the Journal.

The company also said that OxyContin is designed to last longer than other products, which is why the pills tend to have a higher dosage strength, and that the drug’s share of prescription opioids never exceeded 4%.

Purdue and the Sackler family that owns it are trying to resolve some 2,600 lawsuits from states, cities and counties that accuse the company of helping spark the nation’s opioid crisis through its aggressive marketing. On Sunday, the company filed for bankruptcy protection with a partial deal aimed at resolving most of the suits.

Purdue and family members named in lawsuits have broadly denied the allegations and have said they are committed to helping curb opioid addiction.

In recent years, the rapid increase in overdose deaths has been driven primarily by illegal opioids like heroin and illicit fentanyl. But from 1999 to 2014, prescription drugs like oxycodone, hydrocodone and others were the leading causes of opioid overdose deaths in the U.S., according to data from the Centers for Disease Control and Prevention.

A 2013 study published in the journal Pain found that oxycodone was the preferred opioid for 45% of 3,500 opioid-dependent people entering addiction treatment around the U.S., compared with about 29% of those who preferred hydrocodone.

Oxycodone was present in 33% of overdose deaths related to prescription opioids, the most of any drug, and nearly twice the share of hydrocodone-linked deaths, according to a CDC analysis of state medical-examiner data from 2009.

The CDC defines high-dose pills as the equivalent of more than 33 milligrams of oxycodone. The risk of overdose nearly doubles when a patient takes more than 33 milligrams of oxycodone a day, according to the agency.

The headquarters of Purdue Pharma in Stamford, Conn., on Monday. The OxyContin maker filed for bankruptcy protection Sunday.

JOHN MOORE, GETTY IMAGES