Federal agents arrested the founder of a major drug company in an early-morning raid Thursday on charges stemming from an alleged scheme to get doctors to illegally prescribe a powerful opioid to patients who don't need it. John Kapoor ... is the billionaire founder and former CEO of the pharmaceutical company Insys Therapeutics. He faces charges including racketeering, conspiracy, bribery and fraud. Kapoor is the most significant pharmaceutical executive to be criminally charged in response to the nationwide opioid crisis. Kapoor stepped down as CEO of Insys in January but still serves on its board. The company makes a spray version of fentanyl, a highly addictive opioid intended only for cancer patients. Authorities allege Insys marketed the drug as part of a scheme to get non-cancer doctors to prescribe it. Numerous physicians were allegedly paid bribes by the company to push the painkilling drug. Insys made 18,000 payments to doctors in 2016 that totaled more than $2 million. Headache doctors, back pain specialists and even a psychiatrist ... received thousands of dollars to promote the drug last year. Last December, six other Insys executives were indicted on federal charges in Boston in connection with the alleged scheme to bribe doctors to unnecessarily prescribe the painkilling drug.