A Phase 1/2 Open-Label Dose-Escalation Study to Evaluate Safety, Tolerability, Pharmacokinetics, and Efficacy of Intracerebroventricular BMN 190 in Patients With Late-Infantile Neuronal Ceroid Lipofuscinosis (CLN2) Disease

Inclusion Criteria: * Has a diagnosis of CLN2 determined by TPP1 enzyme activity (dried blood spot) available at study entry. If no genotype information is available, blood will be collected for CLN2 gene analysis at baseline. In addition, blood for TPP1 enzyme activity (dried blood spot) will be collected at baseline to be analyzed centrally * Has mild to moderate disease documented by a two-domain score of 3- 6 on motor and language domains of the Hamburg Scale, with a score of at least 1 in each of these two domains * Written informed consent from parent or legal guardian and assent from subject, if appropriate * Has the ability to comply with protocol requirements, in the opinion of the investigator * Seizures are stable in the judgement of the investigator Exclusion Criteria: * Is less than 3 years old at enrollment * Is 16 years old or older at enrollement * Has another inherited neurologic disease, e.g. other forms of CLN or seizures unrelated to CLN2 (patients with febrile seizures may be eligible) * Has another neurological illness that may have caused cognitive decline (e.g., trauma, meningitis, hemorrhage) before study entry * Requires ventilation support, except for noninvasive support at night * Has received stem cell, gene therapy, or ERT for CLN2 * Has contraindications for neurosurgery (e.g., congenital heart disease, severe respiratory impairment, or clotting abnormalities) * Has contraindications for MRI scans (e.g., cardiac pacemaker, metal fragment or c…