On Monday, California district judge Sherilyn Peace Garnett ruled Salvador Plasencia and Jasveen Sangha will face a joint trial on 4 March next year. A pre-trial hearing is also set for 19 February.

The two are among five people who have been charged over the death of the Friends star, who died from the "acute effects of ketamine" on 28 October aged 54.

Perry had been seeking treatment for depression and anxiety when he became addicted to intravenous ketamine.

Court documents say he was taking the drug six to eight times a day before he died.

Plasencia, a doctor from Santa Monica, is alleged to have used Perry's live-in assistant Kenneth Iwamasa to distribute ketamine to the actor from September to October last year for at least $55,000 (£42,500).

Sangha - an alleged drug dealer named by authorities as "the Ketamine Queen" - is said to have sold the drug to Perry for $11,000 (£8,553) in cash.

She would allegedly sell the drug to Eric Fleming, another defendant and an acquaintance of Perry, who would sell it to his assistant.

A drug enforcement administrator previously claimed the ketamine supplied by Sangha was ultimately the dose that took Perry's life.

Plasencia faces a maximum sentence of 120 years in federal prison and has denied charges of conspiracy to distribute ketamine, seven counts of distribution of ketamine and two charges related to allegations he falsified documents during the investigation.

Sangha faces life imprisonment and pleaded not guilty to conspiracy to distribute ketamine, maintaining a drug-involved premises, possession with intent to distribute methamphetamine, possession with intent to distribute ketamine and five counts of distribution of ketamine.

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Iwamasa, Fleming, and a second doctor, Mark Chavez, who sold ketamine that he had previously obtained by writing a fraudulent prescription to Plasencia, pleaded guilty to the charges against them.

Court documents claimed to reveal extensive correspondence between some of the defendants as they allegedly discussed sourcing drugs for Perry, with Plasencia allegedly messaging Chavez: "I wonder how much this moron will pay."