For the once-prominent cancer doctor, it's over.

Farid Fata will spend the next four decades in prison for poisoning patients to make money as the U.S. Supreme Court has refused to hear his case.

In a one-line decision, the nation's highest court wrote Friday that it would not hear Fata's appeal.

The decision comes almost three years after the Michigan doctor pleaded guilty to poisoning hundreds of patients intentionally through unnecessary treatments and raking in more than $17 million from fraudulent billings. He was sentenced to 45 years in prison in 2015.

Fata, a married father of three and a naturalized U.S. citizen whose native country is Lebanon, was charged with running a scheme that involved billing the government for medically unnecessary cancer and blood treatments. Following his arrest in 2013, the federal government seized many of his assets and set up an $11.9-million restitution fund, which was used to help Fata's victims recover medical costs and other expenses.

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The government had seized $13 million in total assets from Fata, but $1.1 million was paid to the whistle-blower in the case, leaving the rest for his victims.

The U.S. Attorney's Office had initially identified 553 victims, but noted there could have been more given that Fata's practice treated 17,000 patients through seven locations.

Fata appealed to the U.S. Supreme Court after the U.S. 6th Circuit Court of Appeals ruled against him, writing: “Fata was able to make false diagnoses and administer potentially deadly, yet, unnecessary, course of treatment for hundreds of patients who relied on his presumed integrity and accepted his presumed professional judgments — all to their detriment and to Fata’s financial gain. Fata occupied a position of trust when he abused his patients by treating maladies with life-threatening chemicals.”

In his appeal, Fata had argued that victim impact statements, both written and oral, should not have been allowed to be heard in his case because — he claimed — some of those patients had not actually been confirmed as victims. The 6th Circuit rejected that argument.

Fata is serving his sentence in South Carolina.