Story highlights Charlie Gard expected to be evaluated in London early next week

A US doctor told the court the baby has an 11% to 56% chance of improvement

(CNN) Baby Charlie Gard, the 11-month-old with a rare, terminal medical condition who has been the center of an ongoing legal battle, will be evaluated by a doctor from the United States.

Charlie will be examined early this week, in London, by Dr. Michio Hirano , a neurologist at New York's Columbia University Medical Center. Hirano is developing an experimental therapy that has been used on at least one American patient with a similar but less severe mitochondrial disease. He specializes in myopathies and other neuromuscular diseases.

Charlie was born in August with mitochondrial DNA depletion syndrome, a progressive disease that causes muscle weakness and loss of motor skills, leaving those who have it unable to stand, walk, eat, talk and eventually breathe. Charlie will die from his illness, his doctors have said.

His parents, Chris Gard and Connie Yates, successfully raised money in hopes of bringing their son to the US for an experimental treatment, but doctors at the Great Ormond Street Hospital in London, where Charlie has been since October, argued in court that it was not in their patient's best interest.

After a series of hearings and appeals in several courts, the European Court of Human Rights decided on June 30 not to intervene in the case, which upheld a British Supreme Court decision that the hospital could discontinue life support to Charlie and he could not be transferred.

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