BMN 110 US Expanded Access Program

Inclusion Criteria: * Diagnosed with MPS IVA as confirmed by either N-acetylgalactosamine-6-sulfatase (GALNS) enzymatic test (GALNS activity in affected range, beta-galactosidase and a second lysosomal sulfatase activity within normal range) or molecular diagnostic test (two mutations in GALNS identified that have previously been associated with an enzyme defect). * Willing and able to provide written, signed informed consent, or in the case of patients under the age of 18, provide written assent (as required by the IRB) and written informed consent by a legally authorized representative after the nature of the program has been explained, and prior to any program assessments or evaluations. * Sexually active patients must be willing to use an acceptable method of contraception while participating in the program. * Females of childbearing potential must have a negative pregnancy test at Baseline and be willing to have additional pregnancy tests during the program. * Willing and able to comply with all program procedures. Exclusion Criteria: * Pregnant or breastfeeding at Baseline or planning to become pregnant (self or partner) at any time during the program. Patients who become pregnant during the program will be discontinued from the program. * Currently enrolled in an ongoing clinical study of BMN 110. * Discontinued from a BMN 110 clinical study secondary to a safety-related event. * Use of any investigational product (other than BMN 110 in a clinical study) or investig…