A 5-Year Study of Glycerol Phenylbutyrate Treatment in Chinese Children and Adolescents With Urea Cycle Disorders

What this Trial Is About

Urea cycle disorders UCD are rare diseases in China that can cause high mortality and disability, requiring long-term management due to recurring symptoms. This multi-center, prospective, single-arm study aims to evaluate the safety and effectiveness of Glycerol Phenylbutyrate in Chinese children with UCD. The goal is to provide more treatment options and improve clinical care for these patients in China. The study plans a total observation period of five years for patients on long-term treatment with this medication. The study involves 40 children aged from birth to 18 years diagnosed with various types of UCD, including carbamoyl phosphate synthetase I deficiency and others. Participants will receive Glycerol Phenylbutyrate oral liquid, with dosing based on body surface area and divided into multiple daily doses taken with meals. The study includes scheduled clinic visits at 1 month and 3 months after enrollment, followed by visits every 6 months up to 5 years. During these visits, researchers collect data on adverse events, dosage changes, hyperammonemic crises, and blood ammonia levels. Participants will undergo regular assessments including blood tests for ammonia and biochemistry, growth measurements height, weight, head circumference, and neurocognitive evaluations at specified intervals. The primary outcome is the mean blood ammonia level at 3 months after enrollment. Secondary outcomes include ammonia levels at multiple timepoints, frequency of crises, growth data, dosage adjustments, and various neurodevelopmental scores measured annually. This comprehensive follow-up aims to monitor safety, treatment effects, and overall development throughout the five-year period.

A Clinical Study of Glycerol Phenylbutyrate in Chinese Patients With Urea Cycle Disorders