Matthew Perry's Assistant Sentenced to Over 3 Years in Death Case

Matthew Perry's ex-assistant is headed to prison for helping supply the ketamine that killed the beloved "Friends" actor ... with a judge handing down the sentence Wednesday.

Kenneth Iwamasa was sentenced to 41 months behind bars after pleading guilty to conspiracy to distribute ketamine resulting in death in connection with Perry’s October 2023 fatal overdose.

Back in 2024, Iwamasa cut a plea deal with federal prosecutors ... they were pushing for a nearly 3 1/2-year sentence -- which is exactly what he got -- and argued Iwamasa became far more than just Perry's assistant -- allegedly acting as the actor's drug supplier and injector despite having no medical training.

According to court docs, Iwamasa admitted he repeatedly injected Perry with ketamine in the weeks leading up to the actor’s death ... allegedly administering more than 20 shots of ketamine in the last 4 days of Perry's life ... at a time he allegedly knew Perry was "spiraling out of control."

The feds also accused Iwamasa of trying to cover his tracks after Perry died ... allegedly deleting evidence, shredding documents and lying to investigators before eventually cooperating with prosecutors as part of a plea deal.

Iwamasa was the final defendant sentenced in the sweeping ketamine investigation tied to Perry's death ... after Dr. Salvador Plasencia got 30 months behind bars, middleman Erik Fleming was sentenced to 2 years, and "Ketamine Queen" Jasveen Sangha received 15 years in prison.