The maker of the powerful painkiller OxyContin and three of its current and former executives pleaded guilty Thursday to misleading the public about the drug’s risk of addiction, a federal prosecutor and the company said.

Purdue Pharma L.P., its president, top lawyer and former chief medical officer will pay $634.5 million in fines for claiming the drug was less addictive and less subject to abuse than other pain medications, U.S. Attorney John Brownlee said.