Study of IV VTS-270 for Infantile Liver Disease Associated With Niemann-Pick Disease, Type C

In the first phase of the study, infants will be treated for a total of 6 weeks, treated twice weekly. Infants will be admitted to the Neonatal Intensive Care Unit (NICU) for the first week of treatment. Procedures during the first week of the study will include blood draws for genetic testing, clinical and research blood draws, urine collection, abdominal ultrasound, peripheral inserted central catheter (PICC) placement, hearing screening, and the first two IV adrabetadex (VTS-270) infusions through the PICC line. Weeks 2-6 will occur on an outpatient basis. During week 2-6, the infant will receive 2 doses per week of adrabetadex (VTS-270) with blood draws and urine collection during weeks 2, 4, and 6. PICC line will be removed after final infusion.

Subjects who demonstrate significant reduction either in the glycine-conjugated trihydroxycholanic acid biomarker or serum bilirubin (direct bilirubin or direct bilirubin: total bilirubin ratio) will be allowed to crossover into the second phase of the study, an open label phase of six months duration in which IV adrabetadex (VTS-270) will be administered monthly for a total of six doses. Month 1-6 procedures will occur on an outpatient basis. Procedures during the second phase include a monthly intravenous line placement. After each monthly visit, the intravenous line will be removed.

Inclusion criteria

• Age 0 to 6 months of age at time of enrollment, both genders, and any race/ethnicity.
• Diagnosis of NPC (either NPC1 or NPC2) based upon meeting any of the two following conditions:

A. Two variants classified as pathogenic or likely pathogenic in NPC1/NPC2 on clinical laboratory testing, or B. One variant classified as pathogenic or likely pathogenic on clinical laboratory testing and a positive NPC biochemical marker (oxysterol or bile acid biomarker or PPCS/Lyso509) test, if acid sphingomyelinase deficiency and cholesterol ester storage disease have been excluded either by clinical molecular testing of the SMPD1 and LIPA genes or by clinical biochemical assay for acid sphingomyelinase and lysosomal acid lipase enzymes (or a combination of enzymatic and molecular testing).

Variants will be interpreted using the American College of Medical Genetics guidelines for the interpretation of sequence variants (2015) and testing must be performed by a CLIA-certified laboratory.

• Subjects with evidence of NPC-related liver disease as defined by direct bilirubin (DB) >2mg/dL or DB/total bilirubin ratio >0.2.
• Ability to travel to a research site.
• Willing to participate in all aspects of trial design including serial blood collections.
• Parent / guardian must provide written informed consent to participate in the study. Because of the age range intended for inclusion, assent will not possible.

Exclusion criteria

• Age > 6 months at time of enrollment in the trial.
• A medical condition (such as clinically significant bleeding diathesis or evidence of immune suppression) that in the opinion of the investigator precludes placement of an intravenous catheter
• An absolute neutrophil count (ANC) of less than 1,500 per microliter.
• A platelet count less than 75,000 per microliter.
• History of severe neonatal encephalopathy, per modified Sarnat including level of consciousness as stupor/coma, absent spontaneous activity, decerebrate posture, flaccid tone, absent suck, absent moro, diverted/nonreactive pupils, lack of heart rate variability, apnea.
• Subjects, who in the opinion of the investigators, are unable to comply with the protocol or have specific health concerns that would potentially increase the risk of participation. Examples of inability to comply include unwillingness to relocate or travel to a study site, suspected noncompliance with study procedures, behavior that jeopardizes the safety or security of the data or study staff, and other causes of inability to comply.
• Concurrent participation in another investigational drug trial.
• History of renal disease or evidence of acute kidney injury defined as serum creatinine greater than 1.5 mg/dL or an increase of at least 0.2-0.3 mg/dL per day.