The source would not have specified whether any other drug makers named in the suit would follow Purdue's example.
A spokesman for Oklahoma's Attorney General Mike Hunter declined to comment. The Attorney General has scheduled a press conference Tuesday afternoon in Tulsa.
In an email Tuesday, Bob Josephson, executive director of communications at Purdue Pharma, said, "We are not commenting yet."
The lawsuit was filed by Hunter against some of the country's leading manufacturers of opioid painkillers, alleging that the deceptive marketing of the past decade has fueled the state's epidemic. Hunter said the defendants – Purdue Pharma, Johnson & Johnson, Teva Pharmaceuticals, Allergan and others – deceived the public into believing that opioids were safe for prolonged use.
On Monday, the Oklahoma Supreme Court dismissed the drug manufacturers' call for the trial to be postponed for 100 days.
The drug manufacturers denied the allegations and maintained that their commercialization was appropriate.
Thirty-six states have filed lawsuits against Purdue and other opioid drug companies. Oklahoma was the first state to be tried, and judicial observers watch the case closely.
The Oklahoma lawsuit was to be the first in the country to appear before a jury that could determine the role of pharmaceutical companies in the opioid epidemic and determine if Big Pharma should bear the costs.