Aug 25 (Reuters) - A U.S. judge in the Purdue Pharma bankruptcy case expects to rule on Friday on the OxyContin maker’s request to approve its settlement of opioid-related litigation. During a hearing on Wednesday, U.S. Bankruptcy Judge Robert Drain in White Plains, New York, said he plans to rule at the end of the week. A trial over the plan and settlement began on Aug. 12. The deal, which Purdue says is worth more than $10 billion, has widespread support but is still opposed by nine U.S. states. Members of the Sackler family who own the company have said they will contribute about $4.5 billion in exchange for legal protections against opioid-related litigation.