Michael Jackson was driven to his death by a mix of greed, power and money, one of his brothers claimed, while saying the star’s doctor “had no business” giving him the drug that killed him.

Speaking before the manslaughter trial of medic Conrad Murray kicks off this month, Jermaine Jackson said those surrounding his brother failed to look after him, as they pushed him to play a lucrative series of comeback gigs.

He described how his brother’s health had clearly deteriorated in the months leading up to his death – when he was rehearsing intensively for the This is It shows in London – but those around him had not told the family.

“Why didn’t somebody call me or Jackie or Tito or Marlon or his family, to say, ‘Come down here, your brother is not acting normal?’ Had we been called, he would be alive today. We would have taken him to the hospital,” he said.

Asked why he thought they didn’t, he told CNN interviewer Piers Morgan: “Because they wanted the show to go on... It’s all about – this is a story about greed and power and money. And not looking at the person in Michael.”

Dr Murray is due in court on September 27 for the long-awaited manslaughter trial over Jackson’s death in June 2009 from an overdose of the powerful drug propofol, prescribed to help him sleep.

Jermaine Jackson said the doctor’s lawyers would try to paint his brother as a drug addict, but dismissed a suggestion that Jackson – who suffered from chronic insomnia – could have forced Murray to give him more propofol. The drug is so powerful that it is used as an anaesthetic during surgery, he noted, adding that as a cardiologist and not an anaesthesiologist, Dr Murray “had no business giving my brother propofol”.

“Being a doctor, you take an oath to care for your patient not to kill them,” he added.

Michael Jackson’s death, on the eve of the planned series of comeback concerts at London’s O2 Arena aimed at reviving his reputation and finances battered by child sex allegations, stunned fans around the world.

Dr Murray’s defence team is expected to argue that Jackson gave himself an excessive dose of the drug while the doctor was out of the room at the singer’s mansion in the affluent Holmby Hills neighborhood west of Los Angeles.