The opioid manufacturer Insys Therapeutics agreed to pay $225 million to settle federal criminal and civil charges that it illegally marketed a highly addictive fentanyl painkiller to doctors, federal prosecutors said on Wednesday. As part of the deal, a subsidiary of Insys will plead guilty to five counts of mail fraud and the company will pay a $2 million fine and $28 million in forfeiture, according to a statement from the United States attorney’s office in Massachusetts.