Actor Manabu Oshio was sentenced Friday to 2 1/2 years in prison for possessing and giving the illegal synthetic drug MDMA to a woman and failing to seek appropriate medical help when she overdosed and died.

Oshio — the first celebrity to be tried under the lay judge system — immediately filed an appeal, his lawyers said, adding the 32-year-old actor was not satisfied that the court didn't believe his testimony.

Prosecutors had demanded a six-year prison term.

The presiding judge in the Tokyo District Court trial, Hiroyuki Yamaguchi, said Oshio had the responsibility to call for an ambulance on Aug. 2, 2009, when Kaori Tanaka's condition seriously deteriorated after the two took the MDMA, commonly known as Ecstasy, that he gave her and had sex in an apartment in Tokyo's Roppongi district.

"The defendant was afraid of being found that he was using illegal drugs, and did not call 119 for an ambulance," Yamaguchi said in the ruling.

"In the end, the defendant wanted to protect his status as a celebrity, his work and family, and failed to act on his responsibility, and there are no extenuating circumstances."

However, the court said there remains a reasonable doubt that the 30-year-old Tanaka's life would have been saved had an ambulance been called, dismissing one of the arguments made by the prosecution.

Oshio's admission to possession of MDMA and another illegal drug called TFMPP was considered in his favor when deciding the sentence, the court said.

Four men and two women served as the lay judges, sitting on the bench with three professional judges in the high-profile trial.

A total of seven court sessions were held before Friday's ruling.

Owing to Oshio's celebrity status, the trial grabbed massive attention.