The settlement is with 43 states, the District of Columbia and three territories, the person said on Wednesday.
The attorneys general of Vermont and North Carolina issued separate media advisories saying there would be announcements on the opioid epidemic on Thursday.
McKinsey did not respond to a request for comment.
Vermont’s attorney general, T.J. Donovan, said he would announce on Thursday the state’s participation in the first multi-state opioid settlement “to result in substantial payment to the states to address the epidemic.” His office did not provide further information.
McKinsey previously came under scrutiny for its role advising Purdue Pharma and the wealth Sackler family that owns the drugmaker.
Massachusetts Attorney General Maura Healey in a lawsuit said that McKinsey advised the Sacklers on how to “turbocharge” sales of opioids.
Purdue filed for bankruptcy in 2019 as part of a proposed settlement it valued at $10 billion that would resolve thousands of lawsuits alleging the drugmaker’s painkiller marketing helped fuel the opioid epidemic.
More than 3,200 lawsuits nationally are pending seeking to hold drug makers, distributors and pharmacies responsible for an opioid addiction epidemic that according to U.S. government data resulted in 450,000 overdose deaths from 1999 to 2018.
The lawsuits accuse drugmakers of deceptively marketing opioids and distributors of ignoring red flags indicating the prescription painkillers were being diverted for improper uses. They deny wrongdoing.
The states and local governments have been also in negotiations for settlements with drug distributors Cardinal Health Inc, McKesson Corp and Amerisourcebergen Corp and drugmaker Johnson & Johnson. Reporting by Nate Raymond, Rama Venkat and Eric Beech; Editing by Leslie Adler