Vertex Pharmaceuticals Inc.’s experimental cystic-fibrosis treatment Orkambi won the backing of a Food and Drug Administration advisory committee, which voted 12-1 on Tuesday to recommend approval of the drug.

The advisory committee included 13 independent doctors, scientists and consumer and patient representatives. The FDA, which is expected to make a final decision on whether to approve Orkambi by July 5, isn’t required to follow the recommendations of such committees, but it usually does.

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