Philip Seymour Hoffman Autopsy Results Inconclusive

Associated Press

Additional tests are needed to determine the actor's exact cause of death, the New York City medical examiner's office said.

Philip Seymour Hoffman's autopsy results were inconclusive, the New York City medical examiner's office told The Hollywood Reporter Wednesday.

Additional tests, including a toxicology study, will need to be done in order to determine the actor's cause and manner of death. Those tests could take anywhere from a few days to a few weeks.

Hoffman, 46, was found dead, with a needle sticking out of his arm, on the bathroom floor of his New York City apartment Sunday. The police also found multiple envelopes of heroin, several used and unused syringes and prescription drugs in the West Village residence. According to CNN, investigators found more than 20 used syringes in a plastic cup and many bags containing white powder.

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The prescription drugs, according to CNN, included the blood-pressure medication clonidine hydrochloride; the addiction-treatment drug buprenorphine; Vyvanse, a drug used to treat hyperactivity disorder; hydroxyzine, which can be used to treat anxiety; and methocarbamol, a muscle relaxer. It is unclear whether the drugs were prescribed for Hoffman.

Hoffman had undergone treatment for drug addiction in the past and said last year that he had been clean for 23 years before "falling off the wagon" in 2012. In May, Hoffman entered a detox facility and completed a 10-day program for his use of prescription drugs and heroin.

The actor left behind three young children, Tallulah, Cooper and Willa, whom he had with his longtime partner, costume designer Mimi O'Donnell. He also had two sisters, Jill and Emily, and a brother, Gordy Hoffman, who scripted the 2002 film Love Liza, in which Philip starred.

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Considered one of the finest actors of his generation, Hoffman won the best actor Oscar for his role as Truman Capote in 2005's Capote and received supporting actor Academy Award nods for his work in Charlie Wilson's War (2007), Doubt (2008) and The Master (2012). He received Tony Award noms for True West (2000), Long Day's Journey Into Night (2003) and, as Willy Loman, in Death of a Salesman (2012).

He recently appeared as Plutarch Heavensbee in The Hunger Games: Catching Fire and was set to repeat that role in the two-part final chapter of the Hunger Games series: Mockingjay. Indeed, Hoffman had nearly completed filming of Mockingjay -- Part 1, set for release in November and had seven days of filming remaining on Part 2. He was also set to star in the Showtime series Happyish.