LONDON — An American doctor testifying in the case of a British couple seeking the right to take their critically ill infant to the United States for treatment said Thursday it is worth trying an experimental therapy that has only recently emerged.

The doctor, whose name and institution cannot be named because of a court order, told Britain’s High Court that new clinical data has emerged about the effectiveness of the treatment proposed for 11-month-old Charlie Gard, who suffers from a rare genetic condition and is on life support.

Judge Nicholas Francis said the doctor should come to London to see Charlie and meet other experts. At the end of an eight-hour court hearing Thursday, Francis said “no hearing can resume” until that happens.

The boy’s family is in a legal battle with Britain’s most famous children’s hospital because they disagree on whether trying the experimental treatment is in Charlie’s best interest. The case attracted international attention after U.S. President Trump and Pope Francis weighed in.

“We have a much better understanding of the data,” the doctor testified, saying the information has emerged in the time since judges first rejected the parents’ bid to take Charlie to America.

Charlie suffers from mitochondrial depletion syndrome, a rare genetic disease that has left him brain damaged and unable to breathe unaided.

Specialists at Great Ormond Street Hospital have fought the parent’s bid for therapy because they don’t think it will help and may cause him pain. The hospital says Charlie should be allowed to die with dignity.

A succession of courts has backed the hospital, but the case returned to the High Court Thursday after claims of new evidence and the high-profile interventions.