Chavez, Fleming and Iwamasa all pleaded guilty.
The U.S. Justice Department said Ms. Sangha and Mr. Placencia are scheduled to appear in court in Los Angeles on Thursday afternoon.
Prosecutors said the defendants tried to cover up their crimes after Perry's death.
Mr. Sangha allegedly texted another suspect, telling him to “delete all our messages.” Mr. Plasencia also falsified medical records, according to the indictment.
Drowning was listed as a contributing factor to Perry's death, which was ruled an accident. Other contributing factors included coronary artery disease and the effects of buprenorphine, a drug used to treat opioid use disorder.
Perry struggled with addiction to painkillers and alcohol at the height of his fame, and went into rehab several times. He detailed his struggles with drug use in his memoir Friends, Lovers, and the Big Terrible Thing.
He told BBC Radio 2 in 2016 that he couldn't remember the three years he spent filming Friends because of drink and drugs.
After trying treatment, he wrote in his memoir that he has been mostly sober since 2001, “except for about 60 or 70 accidents.”
