PTC Therapeutics, Inc. presented real-world results from the STRIDE patient registry demonstrating that treatment with Translarna™ (ataluren) delays loss of ambulation by more than five years in boys with nonsense mutation Duchenne muscular dystrophy (nmDMD) compared to standard of care (SoC) alone. Pulmonary function decline was also delayed by 1.8 years in those treated with Translarna and SoC. A time-to-event analysis of five years of registry data, presented at the World Muscle Society (WMS) 2021 Virtual Congress, shows that boys treated with Translarna plus SoC had a median age of loss of ambulation of 17.9 years old compared with 12.5 years old for those on SoC alone. At 12 years old, 80% of boys receiving Translarna plus SoC are still walking, compared to 52% of the boys receiving SoC alone. The median age that boys treated with Translarna reached a predicted forced vital capacity (FVC) lower than 60% was 17.6 years old, compared with 15.8 years old for those who did not receive Translarna. This delay in loss of lung function is critical, as the sub-60% threshold is considered the milestone at which patients usually start to require respiratory physical therapy. The data was compared with natural history from a propensity-score matched cohort in a long-term natural history study (the Cooperative International Neuromuscular Research Group (CINRG) natural history database of Duchenne patients). Translarna continues to be well tolerated in nmDMD patients, and the safety results, representing 1059 patient-years of exposure, remain consistent with the therapy's known safety profile.