The trial of famous German painter and art professor, Jörg Immendorf, accused of possessing cocaine and organizing sex orgies with prostitutes, got underway in a Düsseldorf courtroom on Tuesday. Known as German Chancellor Gerhard Schröder's favorite artist, Immendorf fell from grace when he was caught with nine prostitutes in a Düsseldorf hotel room in August last year. He faces criminal charges of possessing cocaine in 27 cases. A student of artist Joseph Beuys and a respected professor at the Düsseldorf Art Academy, Immendorf won the prestigious Marco Prize of the Monterey Museum in Mexico in 1997. Immendorf, who suffers from the incurable ALS neurodegenerative disease, cut a frail figure in court on Tuesday. He has admitted to all the charges, but has denied having sex with any of the prostitutes. "It was only about living out my fantasies," Immendorf said. The 59-year-old said he regretted his "wrong behavior, in particular towards my family."