Amendment 1: 1. To permit sufficient study drug clearance, based on nonclinical data, the follow-up visit was changed from 4 weeks to 6 months. 2. To ensure additional precaution for subject safety, during the first dosing cohort, at least 72 hours must have elapsed between the first and second subjects. 3. To require antihistamine pretreatment, it was clarified that an antipyretic medication may not be substituted but may be added, if appropriate. 4. To be consistent with European ethics committee recommendations, subjects 16 years of age or older were excluded from study participation. 5. To add a precautionary measure for this pediatric study population, females of child-bearing potential were excluded from study participation.

Amendment 2: 1. Added rationale for investigational drug infusion volume and rate. 2. Added statement regarding subject sedation during infusion at the discretion of the investigator. 3. Added statement regarding monitoring for epileptic seizure during infusion and for interrupting infusion at the discretion of the investigator. 4. For safety variables, removed head circumference assessment and replaced “length” with “height” assessment in complete physical exam. 5. Added statements regarding procedure for evaluating status of ICV access device on a regular basis. Specifically, “Surgical implantation of an ICV access device will take place prior to study drug administration. The investigator will evaluate the patency, location, and skin integrity of the reservoir at each study drug administration. At the discretion of the investigator and/or neurosurgeon, the ICV access device may be replaced during the clinical study.”

Amendment 3: 1. The schedule for Magnetic resonance imaging (MRI) during the Stable Dose Period for quantitative analysis was changed be done at four time points: Baseline or Week 1 in the Stable Dose Period, and at Weeks 9, 25, and 49 in the Stable Dose Period. A screening MRI was required prior to ICV access device placement for anatomic localization. If sedation or anesthesia were required for this image sequence, the ICV access device placement would occur in the same period. 2. All adapted CLN2 scale assessments were videotaped at all site visits where the adapted CLN2 scale assessments are done. 3. For the post-implantation, first dose, and dose-escalation visits, subjects were monitored for 48 hours after infusions (with a minimum of 24 hours in the pediatric intensive care unit [PICU], and the remaining time on an inpatient ward). A follow-up phone call was also conducted within 24 hours after inpatient discharge. 4. Planned enrollment in the study was changed from 22 to “approximately 22” subjects. 5. Language was added concerning the collection of device-related adverse events (AEs) prior to the first administration of study drug. 6. Language was added detailing the risks of intracerebroventricular drug administration. 7. It was clarified that all Screening procedures are to be completed ≤ 3 days prior to the ICV access device implant surgery. 8. Baseline total and drug-specific IgE assessment was added.

Amendment 4: 1. Device-related AE reporting requirements were amended to include all infusion system components that come into contact with BMN 190. 2. Subjects and their caregivers were given written instructions following ICV placement providing details about signs and symptoms of potential device complications or failure.

Amendment 5: 1. Device-related AE reporting requirements were amended to include all infusion system components. 2. Language was clarified that, for Stable Dose Period visits, subjects would be closely monitored in an inpatient setting for up to 48 hours following each infusion, but could be discharged after 24 hours if medically stable and if no safety issues were observed.