(Reuters) - A former physician assistant in New Hampshire was convicted on Tuesday of charges that he accepted nearly $50,000 in kickbacks from Insys Therapeutics Inc INSY.O in exchange for prescribing its addictive fentanyl spray.

FILE PHOTO: Christopher Clough, a former physician assistant, arrives at the federal courthouse in Concord, New Hampshire, U.S., December 12, 2018. REUTERS/Nate Raymond/File Photo

A federal jury in Concord, New Hampshire, found Christopher Clough, 45, guilty of all charges he faced in a case that stemmed from a years-long investigation into the Arizona company’s efforts to promote its opioid medication Subsys.

Clough is scheduled to be sentenced on March 29. Patrick Richard, Clough’s lawyer, said he is evaluating his options, including an appeal.

The verdict came a month before six former Insys executives and managers including John Kapoor, a onetime billionaire who was its founder and chairman, face trial on charges that they conspired to bribe medical practitioners to prescribe Subsys.

The under-the-tongue spray is meant only for treating pain in cancer patients and contains fentanyl, an opioid 100 times stronger than morphine.

Prosecutors in that case allege Kapoor and his co-defendants conspired to bribe doctors and others like Clough by paying them fees to participate in speaker programs ostensibly meant to educate medical professionals about Subsys that were actually shams.

Federal prosecutors in Boston have said they plan to introduce evidence about Clough at the trial of Kapoor, former Chief Executive Michael Babich and their co-defendants. They have pleaded not guilty.

Prosecutors said Clough, who worked at a clinic called PainCare in Somersworth, New Hampshire, accepted nearly $50,000 from Insys to act as a speaker while prescribing Subsys to mostly non-cancer patients.

Witnesses at Clough’s trial included two ex-members of Insys’ sales staff, Jeffrey Pearlman and Natalie Babich, who previously pleaded guilty to conspiring to pay kickbacks and agreed to cooperate with prosecutors.

Babich, a former sales representative who is now married to Michael Babich, testified Clough frequently got paid for being a speaker at dinners with her with no other attendees.

Pearlman, a former district sales manager, testified that Insys used speaker fees to get doctors “more and more hooked on the company.”

Clough’s lawyers contended that he had no idea Insys was trying to bribe medical practitioners like himself and that he prescribed Subsys because he thought it would help his patients.

In August, Insys said it had agreed to settle a related U.S. Justice Department probe for at least $150 million. It resolved a probe by New Hampshire’s attorney general focused on payments to Clough for $3.4 million in 2017.