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

NCT06904027 | Recruiting

• 1 other identifier: WH002A401
• Study Type: observational
• Target: 40
• Locations: 1 country
• Sites: 5

Brief Summary

Urea cycle disorders (UCD) are rare diseases in China, would lead to high mortality and disability, which require long-term management due to the recurrent symptoms. This multi-center, prospective, single-arm study was designed to assess the efficacy and safety of Glycerol Phenylbutyrate for Chinese pediatric patients with UCD, to provide the additional references and treatment options for Chinese UCD patients, and enhance the clinical management of UCD in China. This study primarily observes patients with UCD who are on long-term treatment with glyceryl phenylbutyrate, the total planned observation period is 5 years.

Conditions

Urea Cycle Disorders

Keywords

Chinese; Pediatric patients; Urea cycle disorders; Glycerol phenylbutyrate

Outcome Measures

Primary Outcomes (1)

• Mean blood ammonia levels at month 3 after enrollment.

  The average of blood ammonia levels at months 3 after enrollment.

  months 3

Secondary Outcomes (12)

• Mean blood ammonia levels

  Baseline, Month 1, Month 6, and every 6 months thereafter (1-5 years)

• Maximum blood ammonia levels

  Baseline, Month 1, Month 3, Month 6, and every 6 months thereafter (1-5 years)

• Frequency of hyperammonaemic crisis

  Baseline, Month 1, Month 3, Month 6, and every 6 months thereafter (1-5 years)

• Height

  Baseline, Month 1, Month 3, Month 6, and every 6 months thereafter (1-5 years).

• Weight

  Baseline, Month 1, Month 3, Month 6, and every 6 months thereafter (1-5 years)

Study Arms (1)

Glycerol phenylbutyrate cohort

Glycerol Phenylbutyrate was used.

Drug: Glycerol phenylbutyrate Oral Liquid

Interventions

Glycerol phenylbutyrate Oral Liquid DRUG

Administration and dosage: The recommended total daily dose of glycerol phenylbutyrate is calculated based on the patient's body surface area, ranging from 4.5 mL/m2/d to 11.2 mL/m2/d: 1. Recommended initial dose in phenylbutyrate-naïve patients * Patients with body surface area (BSA) \< 1.3 m2: 8.5 mL/m2/day * Patients with body surface area (BSA) ≥ 1.3 m2: 7 mL/m2/day 2. Initial dose for patients switching from sodium phenylbutyrate to glycerol phenylbutyrate: Total daily dose of glycerol phenylbutyrate (ml) = total daily dose of sodium phenylbutyrate granules (g) ×0.81 Medication Schedule: The daily total dose should be divided into equal amounts and administered with each meal or feeding (such as three to six times daily).

Also known as: HPN-100, GT4P, Glyceryl tri-(4-phenylbutyrate), RAVICTI

Glycerol phenylbutyrate cohort

Eligibility Criteria

• Age: 0 Years - 18 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)
• Sampling Method: Probability Sample

Study Population

Long term treatment for pediatric patients with UCD, aged 0-18 years, who cannot be managed with protein restriction and/or amino acid supplementation alone, including carbamoyl phosphate synthetase I deficiency, ornithine carbamoyltransferase deficiency, citrullinemia type I, argininosuccinic aciduria, argininemia, and hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome.

You may qualify if:

• Male or female aged 0-18 years;
• Subject and/or subject's legally authorized representative willing to follow the therapeutic regimen, dietary management and visit plan of the study, and voluntarily signing informed consent form;
• Patients with the following subtypes of UCD: Carbamoyl phosphate synthetase I deficiency, Ornithine translocase deficiency, citrullinemia type I, argininosuccinic aciduria, argininemia, and hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome;
• Patients planned to use glycerol phenylbutyrate who have not used it in past 3 months (including at the time of 3 months);
• Men with fertility and women of childbearing potential (with menstruation) who are willing to take effective contraceptive measures during the period from the date of signing the informed consent to 1 months after the last dose of the study drug, such as abstinence, condoms, intra-uterine contraceptive devices, and double barrier methods (such as condoms + contraceptive diaphragms). Pregnancy test results must be negative for women of childbearing age within ≤ 7 days before the initial administration of study drug.

You may not qualify if:

• Hypersensitivity to any of the active ingredient, including phenylbutyrate (PBA), phenylacetate acid (PAA) and phenylacetyl glutamine (PAGN), or excipients;
• Use of any drug known to significantly affect renal clearance (such as probenecid) or increase protein catabolism (such as corticosteroids) or other drugs known to increase blood ammonia levels (such as valproate) within 24 h before the first administration;
• Use of other nitrogen-scavenging agent at the same time after enrollment, such as sodium phenylbutyrate and sodium benzoate;
• Pregnant or breastfeeding females.
• Other reasons, in the opinion of the investigator, that may affect the patient's compliance and safety in participating in the study.

Sponsors & Collaborators

• Tongji Hospital: lead

Study Sites (5)

Peking University First Hospital

Beijing, Beijing Municipality, 100034, China

RECRUITING

Guangzhou Women and Children's Medical Center

Guangzhou, Guangdong, 510000, China

RECRUITING

Tongji Hosipital

Wuhan, Hubei, 430030, China

RECRUITING

Xinhua Hospital, Shanghai Jiao Tong University School of Medicine

Shanghai, Shanghai Municipality, 200092, China

RECRUITING

Children's Hospital of Zhejiang University School of Medicine

Hangzhou, Zhejiang, China

NOT YET RECRUITING

MeSH Terms

Conditions

Urea Cycle Disorders, Inborn

Interventions

glycerol phenylbutyrate

Condition Hierarchy (Ancestors)

Brain Diseases, Metabolic, Inborn; Brain Diseases, Metabolic; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Amino Acid Metabolism, Inborn Errors; Metabolism, Inborn Errors; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Metabolic Diseases; Nutritional and Metabolic Diseases

Study Officials

• Xiaoping Luo, M.D.

  Tongji Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Xiaoping Luo, M.D.

CONTACT

027-83662640; xpluo@tjh.tjmu.edu.cn

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: March 10, 2025
• First Posted: April 1, 2025
• Study Start: December 9, 2025
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): July 1, 2031
• Last Updated: January 15, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

CN (5)