Intravitreal ERT to Prevent Retinal Disease Progression in Children With CLN2

Inclusion Criteria: * Genotypic confirmation of classical CLN2 Batten's disease from a CLIA certified lab. * Enzyme level deficiency of tripeptidyl-peptidase * Minimum age requirement: 24 months of age at enrollment * Maximum age requirement: 72 months of age at enrollment * Currently receiving intraventricular cerliponase alfa * Willing to participate in the proposed study visits over the 2-year period * Minimum central retinal thickness (CRT) of 140μm based upon OCT assessment * Clear ocular media * No ocular pathology present to account for vision loss other than optic atrophy and pigmentary retinopathy that is felt to be due to the CLN2 disease process Exclusion Criteria: * Any opacities in the clear ocular media including vitreous debris. * History of ocular trauma or prior ocular surgery. * Episode of generalized motor status epilepticus within four weeks before the First Dose visit * Severe infection (e.g., upper respiratory tract infection, pneumonia, pyelonephritis, or meningitis) within four weeks before the First Dose visit (enrollment may be postponed) * Those with a history of bleeding disorders. * History of or current chemotherapy, radiotherapy or other immunosuppression therapy within the past 30 days (corticosteroid treatment may be permitted at the discretion of the PI) * Has a medical condition, or extenuating circumstance that, in the opinion of the investigator, might compromise the subject's ability to comply with the protocol required testing or proc…