An experimental sedative created at Kansas University and developed by a Lawrence-based startup company is headed for advanced clinical trials early next year, the drug’s owner said Wednesday.

MGI Pharma Inc. said it soon would begin final studies needed for approval of the surgical sedative, known as Aquavan. The company also revealed results of a mid-stage trial showing that higher doses of the drug – 6.5 milligrams per kilogram and 8 milligrams per kilogram – proved most effective.

Upcoming trials will use patients undergoing examinations that use sedation – colonscopies and bronchoscopies – plus patients undergoing minor surgeries. Enrollment in all three trials should take about a year, MGI said.

The Bloomington, Minn.-based drug maker acquired Aquavan when it bought Guilford Pharmaceuticals Inc. in October. Guilford had bought the drug from Lawrence-based ProQuest Pharmaceuticals, which had taken it out of research laboratories at KU.

Shares of MGI Pharma rose $1.78, or 11.2 percent, to close at $17.72 Wednesday on the Nasdaq.