ABSTRACT
Abstract Mucopolysaccharidosis VI (MPS VI) is a progressive lysosomal storage disorder with multiorgan and multisystemic pathology. Currently, galsulfase enzyme replacement therapy (ERT) is the only approved treatment for MPS VI. A crosssectional survey study of 121 patients with MPS VI conducted in 2001 to 2002 and a 10-year follow-up study of the same patients (resurvey study; ClinicalTrials.gov NCT01387854) found that those receiving galsulfase at any time showed physical improvements and a lower mortality rate (16.5%) versus treatment-naive patients (50%). After *15 years, galsulfasetreated patients (n » 104) continue to have a survival advantage over treatment-naive patients (n » 14), as demonstrated by a 24% versus 57% mortality rate. This survival advantage is further supported by data from the commercial use of galsulfase (2005-2016), which show a 5-year mortality rate for galsulfase-treated patients of 12.5%. Together, these findings suggest that galsulfase ERT can increase life expectancies for patients with MPS VI over a period of at least 15 years.