New York City and 21 counties around the state have sued the consulting firm McKinsey & Company for its work helping Purdue Pharma market OxyContin, the drug at the center of the opioid addiction epidemic.

Attorneys from Simmons Hanly Conroy signed the complaint, which alleges McKinsey worked with Purdue after 2007, when the company pleaded guilty to criminal misbranding related to OxyContin, to “circumvent” Purdue’s agreement as part of the guilty plea to avoid making deceptive or misleading claims about the painkiller.