WASHINGTON — Congress gave final approval on Tuesday to a bill that would allow patients with serious illnesses to try unproven experimental treatments, sending the measure to President Trump, a strong supporter of the legislation.

By a vote of 250 to 169, the House passed the same “right to try” bill that was approved in August by unanimous consent in the Senate.

The bill would, in effect, allow dying patients to bypass the Food and Drug Administration and obtain an “investigational drug” with the approval of their doctors, if the drug manufacturer agrees to supply it.

On at least three occasions in the past four months, Mr. Trump has urged Congress to pass the bill.

“Patients with terminal conditions, and terminal illness, should have access to experimental treatment immediately” and “should not have to go from country to country to seek a cure,” he said in January in his State of the Union address.