Cadden, 50, owner and head pharmacist of the New England Compounding Center, was convicted of racketeering, racketeering conspiracy, mail fraud and introduction of misbranded drugs into interstate commerce with the intent to defraud and mislead.
He was acquitted of 25 counts of second-degree murder.
"We are very gratified by the verdicts today. ... Those are extremely serious offenses, and they carry very stiff penalties," said William Weinreb, acting U.S. attorney for the District of Massachusetts, after the verdict was announced. "Of course, we're disappointed that the jurors did not also find that he committed the second-degree murder predicate counts."
More than 700 people in 20 states were diagnosed with fungal meningitis
and other infections after receiving contaminated medication in 2012. Sixty-four patients in nine states died, making it the deadliest meningitis outbreak in US history.
The deaths were caused by contaminated vials of preservative-free methylprednisolone acetate, a steroid manufactured by the compounding pharmacy.
The U.S. Attorney's Office said
Cadden authorized the shipping of drugs that weren't confirmed to be sterile and used expired ingredients. It added that the compounding center did not comply with cleaning, sterilization and other safety regulations -- and that many who worked there, from its owners to pharmacists, actively lied about it.
According to the U.S. Attorney's Office, the compounding center used fictional and celebrity names on fake prescriptions to dispense drugs, such as "Michael Jackson," "Freddie Mae" and "Diana Ross."
The US Justice Department noted in 2014 that the murder charges do "not require the government to prove Cadden and supervisory pharmacist, Glenn A. Chin had specific intent to kill the 25 patients, but rather that (they) acted with extreme indifference to human life." But on Wednesday, jurors did not find Cadden directly responsible for those 25 deaths, only the racketeering and fraud charges.
"We don't know what the jury was thinking other than what they said, but to us, the murder counts were the ones that were most important, and those were the ones we were most concerned about," Cadden's lead attorney, Bruce Singal, said outside court.
US District Court Judge Richard Stearns scheduled sentencing for June 21. Cadden faces a maximum sentence of 20 years in prison on each of the mail fraud and racketeering counts, according the US Attorney's Office.