Study of Safety, Tolerability and Efficacy of PBKR03 in Pediatric Subjects With Early Infantile Krabbe Disease

PBKR03 is an adeno-associated viral vector serotype Hu68 carrying the gene encoding for human galactosylceramidase, GALC, formulated as a solution for injection into the cisterna magna. This is a global interventional, multicenter, single-arm, dose escalation, study of PBKR03 delivered as a one-time dose administered into the cisterna magna of subjects with early infantile Krabbe Disease. The dose-ranging portion of the study will enroll independent dose escalation cohorts in two age groups of subjects with early infantile Krabbe disease: * Cohort 1: 3 subjects aged ≥4 to \<9 months will receive the low dose (Dose I) * Cohort 2: 3 subjects aged ≥4 to \<9 months will receive the high dose (Dose II) * Cohort 3: 3 subjects aged ≥1 to \<4 months will receive the low dose (Dose I) * Cohort 4: 3 subjects aged ≥1 to \<4 months will receive the high dose (Dose II) Part 1 of the study will enroll a total of four cohorts, enrolled sequentially with separate age-based dose-escalation cohorts. Enrollment will initiate in Cohort 1. Following completion of Cohort 1, simultaneous enrollment in Cohort 2 and Cohort 3 will occur. Cohort 4 will follow completion of cohort 3. The confirmatory cohort, Part 2, will enroll subjects with early infantile Krabbe Disease, aged \>1 to \<9 months. These subjects will receive a dose chosen based on the data obtained in part 1 of the study This will be a 2-year study with a 3-year safety extension.