A pharmaceutical company is being accused of "greedy" high-pressure sales tactics to promote unapproved uses of a potent fentanyl opioid spray, and of setting up sham lectures to provide kickbacks to Minnesota doctors who prescribed it.

In a lawsuit filed Wednesday, Minnesota Attorney General Lori Swanson said that Insys Therapeutics violated federal laws that prevent off-label marketing of prescription drugs, and recklessly promoted a drug that is only supposed to be used to manage intense cancer pain.

"It just seems like the company is playing games with patients' lives," she said.

Documents obtained by subpoena outlined how Insys salespeople were coached to aggressively promote the drug, Subsys, for purposes beyond cancer, to recommend higher initial doses than federally recommended, and to latch onto doctors who were susceptible to marketing influence.

"They call them golden gem physicians," Swanson said.

The lawsuit, which was filed in Hennepin County District Court, builds on other actions taken nationally against Phoenix-based Insys, whose founder and top executives were indicted in Massachusetts over the past two years for alleged kickback schemes to entice doctors to prescribe their drug.

Insys Therapeutics has run into problems in other states, including Massachusetts where executives were indicted.

It also occurs amid a rising rate of drug overdose deaths linked to opioids, particularly to fentanyl — which is considerably stronger than most prescription opioid painkillers and heroin.

Swanson said her office is considering legal action against other opioid manufacturers, but that it wanted to hold this company specifically accountable for marketing tactics that she called "brazen" and "crass."

Sales representatives were encouraged to "win big" by selling as much of the drug as possible, according to one communication from the company.

"Win big?" Swanson said. "That type of talk has no place in medicine."

In a written statement, Insys pledged reforms: "Our new management team takes the allegations of past wrongdoing by former employees with the greatest seriousness and has focused extensively on instilling the highest respect for fundamentally sound values among all of the company's more than 300 current employees."

Federal law allows doctors to prescribe drugs for something other than their listed purposes, but prohibits drug companies from marketing them "off-label." Minnesota also prohibits most gifts from pharmaceutical companies to doctors, and the lawsuit alleges that this state law was violated.

Insys representatives appeared to host "sham" educational sessions that were mostly just one-on-one talks with doctors to promote the drug, said Cody Wiberg, executive director of the Minnesota Board of Pharmacy. In addition to joining the lawsuit, the pharmacy board is filing administrative claims in Minnesota against Insys and its pharmaceutical licenses in the state.

Two doctors received the majority of payments in recent years from Insys for attending multiple meetings branded as educational sessions, Swanson said. "These two physicians became the company's top prescribers in Minnesota."

Swanson said she forwarded the identities of these doctors to the Minnesota Board of Medical Practice.

A Star Tribune review of Medicare open payment records found that Insys paid nearly $70,000 to Minnesota physicians between 2013 and 2016. Most of that went to two pain specialists, neither of whom are oncologists. One in St. Paul received $36,000 and another in Edina received $17,000, federal records show.

Company records show that at least 17 Minnesota doctors prescribed Subsys between 2013 and mid-2017. Eighty percent of the doses prescribed were above the federally recommended initial dosage.

Subsys is approved to manage cancer pain, Swanson noted, but only for cancer patients who are already taking other opioids and finding the pain still intolerable. It is administered as a spray under the tongue.

It is unclear whether any recent fatal opioid overdose cases in Minnesota were specifically due to Subsys, Wiberg said, but the spray formulation would make it an attractive target to abuse.

The Minnesota Department of Health earlier this month reported a 74 percent increase from 2016 to 2017 in overdose deaths related to fentanyl and other synthetic opioids.

Subsys prescriptions made up a fraction of opioid usage, though, according to Insys. While as many as 650,000 people received opioid prescriptions in 2015, only 44 received Subsys that year.