PITTSBURGH — A judge has upheld a jury verdict that a former Pennsylvania medical researcher purposely killed his neurologist wife by cyanide poisoning.

Sixty-seven-year-old Robert Ferrante has been serving a life sentence since an Allegheny County jury convicted him in November 2014 of the death of Dr. Autumn Klein.

Prosecutors say Ferrante killed his 41-year-old wife in 2013 by lacing an energy drink with cyanide and giving it to her under the guise of promoting fertility.

Ferrante’s lawyer, Chris Eyster, argued that prosecutors didn’t have sufficient probable cause for search warrants to obtain certain evidence, and raised questions about a lab that confirmed the poison in Klein’s body.

The Pittsburgh Post-Gazette first reported Tuesday on Common Pleas Judge Jeffrey Manning’s decision, released last week.