Ataluren (Translarna) is a small-molecule drug approved in Europe for the treatment of Duchenne muscular dystrophy caused by a nonsense mutation. Ataluren interacts with the ribosome enabling it to read through premature nonsense stop signals on mRNA and allowing the cell to produce a full-length, functional protein. Ataluren is also being tested in phase III for cystic fibrosis caused by a nonsense mutation.