Study of BMN 110 in Pediatric Patients < 5 Years of Age With Mucopolysaccharidosis IVA (Morquio A Syndrome)

Inclusion Criteria:

- Less than 5 years of age at the time of the first study drug infusion

- Documented clinical diagnosis of MPS IVA based on clinical signs and symptoms of MPS
IVA and documented reduced fibroblast or leukocyte GALNS enzyme activity or genetic
testing confirming diagnosis of MPS IVA

- Written informed consent provided by parent or legally authorized representative
after the nature of the study has been explained and prior to any research-related
procedures.

Exclusion Criteria:

- Previous hematopoietic stem cell transplant (HSCT).

- Previous treatment with BMN 110.

- Known hypersensitivity to any of the components of BMN 110.

- Major surgery within 3 months prior to stuy entry or planned major surgery during the
52-week treatment period.

- Use of any investigational product or investigational medical device within 30 days
prior to Screening, or requirement for any investigational agent prior to completion
of all scheduled study assessments.

- Concurrent disease or condition, including but not limited to symptomatic cervical
spine instability, clinically significant spinal cord compression, or severe cardiac
disease that would interfere with study participation or safety as determined by the
Investigator.

- Any condition that, in the view of the Investigator, places the patient at high risk
of poor treatment compliance or of not completing the study.