The McKinsey & Company consulting firm has agreed to pay $650 million to settle a federal investigation into its work to help opioids manufacturer Purdue Pharma boost the sales of the highly addictive drug OxyContin, per court papers filed in Virginia on Friday. The AP reports that, as part of the deal with the US Justice Department, McKinsey will avoid prosecution on criminal charges if it pays the sum and follows certain conditions for five years, including ceasing any work on the sale, marketing, or promotion of controlled substances, according to the court papers.