(Reuters) - A former owner of a Massachusetts compounding pharmacy whose mold-tainted drugs sparked a deadly U.S. fungal meningitis outbreak in 2012 has pleaded no contest to involuntary manslaughter charges over the deaths of 11 Michigan residents.

The plea by Barry Cadden, the former president of New England Compounding Center, was announced on Tuesday by Michigan Attorney General Dana Nessel and resolves a criminal case her office brought against him in state court in 2018.

The state's charges came after federal juries in Boston in 2017 convicted Cadden and NECC's supervisory pharmacist, Glenn Chin, of racketeering and fraud but cleared them of second-degree murder over 25 deaths nationally caused by tainted drugs the company produced.

Prosecutors said those deaths stemmed from a fungal meningitis outbreak traced back to mold-tainted steroids that Framingham, Massachusetts-based NECC produced in filthy and unsafe conditions and sold to hospitals and clinics nationally.

The outbreak sickened 793 patients, more than 100 of whom have died, prosecutors said.

Prosecutors in Michigan, a state that was among the hardest hit during the outbreak, following the federal trials then charged Cadden and Chin with 11 counts each of second-degree murder over deaths in their state.

Nessel in a statement said her office "worked closely with the families of these victims, and we've ensured that this plea fits their desire for closure and justice."

Under the terms of the plea deal, Cadden, 57, on Monday pleaded no contest to manslaughter charges and agreed to be sentenced to 10 to 15 years in prison, which would run concurrently with his already-imposed federal sentence of 14-1/2 years.

That federal sentence relates to misrepresentations that prosecutors say Cadden made to NECC customers about its drugs.

He is scheduled to be sentenced by a judge in Livingston County, Michigan, on April 18. A lawyer for Cadden did not immediately respond to a request for comment.

Charges in Michigan remain pending against Chin, who has pleaded not guilty and is serving a 10-1/2 year federal sentence. His lawyer declined to comment.