Glycerol Phenylbutyrate is a nitrogen-scavenging pharmaceutical active ingredient used for the long-term management of urea cycle disorders (UCDs). It is a triglyceride containing three phenylbutyrate groups esterified to glycerol.
After oral administration, glycerol phenylbutyrate is hydrolyzed to phenylbutyrate, which is subsequently metabolized to phenylacetate. Phenylacetate conjugates with glutamine to form phenylacetylglutamine, which is excreted through the kidneys and provides an alternative pathway for nitrogen elimination.
Glycerol Phenylbutyrate is a specialized pharmaceutical ingredient used in oral formulations for nitrogen-scavenging therapy. Its manufacturing involves controlled chemical synthesis, purification and comprehensive analytical characterization of the ester and related impurities.
CAS Number: 611168-24-8
Molecular Formula: C33H38O6
Molecular Weight: 530.66 g/mol
Synonyms: Glycerol Phenylbutyrate, Phenylbutyric Acid Glycerol Ester
Drug Class: Nitrogen Scavenger
Therapeutic Class: Urea Cycle Disorder Therapy
Therapeutic Area: Metabolic Disorders / Inherited Metabolic Diseases
Glycerol phenylbutyrate acts as a nitrogen-scavenging agent. Its metabolites provide an alternative route for nitrogen excretion.
Phenylbutyrate is converted to phenylacetate, which binds glutamine to form phenylacetylglutamine. This metabolite is eliminated in urine, carrying two nitrogen atoms per molecule and thereby reducing the nitrogen burden in patients with impaired urea-cycle function.
Glycerol Phenylbutyrate is used for the chronic management of patients with urea cycle disorders who cannot be adequately managed by dietary protein restriction and/or amino-acid supplementation alone.
It is used across several UCDs, including deficiencies involving enzymes of the urea cycle, according to applicable approved labeling.
Urea cycle disorders can lead to accumulation of ammonia because the body cannot efficiently convert nitrogen into urea. Glycerol phenylbutyrate provides an alternative nitrogen disposal pathway through its conversion to phenylacetate and subsequent formation of phenylacetylglutamine.
Glycerol Phenylbutyrate is a lipophilic glycerol ester consisting of three phenylbutyrate groups attached to glycerol. It is a clear, colorless to slightly yellow oily liquid at room temperature and has very low water solubility.
Glycerol Phenylbutyrate API quality evaluation may include:
Glycerol Phenylbutyrate should be stored in a tightly closed container under controlled pharmaceutical conditions and protected from excessive heat, moisture and direct light. Exact storage requirements should follow validated stability data and the applicable product-specific specification.
Glycerol Phenylbutyrate is an established nitrogen-scavenging therapy and remains relevant to pharmaceutical research involving urea cycle disorders, hyperammonemia and inherited metabolic diseases.
Glycerol Phenylbutyrate is a nitrogen-scavenging pharmaceutical API with CAS Number 611168-24-8, molecular formula C33H38O6, and molecular weight 530.66 g/mol. It is a triglyceride ester of phenylbutyrate that provides an alternative pathway for nitrogen elimination in patients with urea cycle disorders.
| Parameter | Specification |
|---|---|
| Appearance | White to off-white crystalline powder |
| Identification | Conforms by IR and HPLC |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Heavy Metals | NMT 10 ppm |
| Water Content | ≤0.5% |