Title
A Study of Glyceryl Tri-(4-phenylbutyrate) (GT4P)
A Randomized, Crossover, Open-label Phase 1 Study of Glyceryl Tri-(4-phenylbutyrate) (GT4P)
Phase
Phase 1Lead Sponsor
Horizon PharmaStudy Type
InterventionalStatus
Completed No Results PostedIndication/Condition
HealthyIntervention/Treatment
glycerol phenylbutyrate phenylacetic acid sodium phenylbutyrate sodium benzoate ...Study Participants
24To determine the safety and tolerability of single oral doses of HPN-100 as a formulation (GT4P-F) and GT4P as the active pharmaceutical ingredient (GT4P-API) administered to healthy male subjects.
A randomized, open-label, four-treatment, four-period crossover study in which healthy male subjects received a single dose of each of the following four treatments on four separate dosing days, 7 days apart:
Oral sodium phenylbutyrate (Buphenyl®) equivalent to 3 g/m2 of 4-phenylbutyric acid (PBA) per dose
Oral GT4P-F mole equivalents to 3 g/m2 of PBA per dose
Oral GT4P-API mole equivalents to 3 g/m2 of PBA per dose
Intravenous 10% sodium phenylacetate plus 10% sodium benzoate (Ammonul®) 2.75 g/m2
HPN-100 is a triglyceride that has a similar mechanism of action as Buphenyl. It is a liquid with minimal taste and odor. HPN-100 is broken down to phenylbutyric acid (PBA). PBA is converted to phenyl acetic acid (PAA) that is the active metabolite. Three teaspoons of HPN-100 (~17.4mL) delivers equivalent amount of PBA that 40 tablets of NaPBA do.
GT4P-F (80% GT4P) was supplied as an odorless, colorless, tasteless liquid oil in 125 ml bottles. This formulation was designed to be mixed in water and create a self-emulsifying suspension, thus administered in water for the trial. The administered dose was calculated to contain the number of moles of PBA equivalent to 3 g/m2 of PBA. GT4P-F was mixed in 50 ml of water, taken orally, and then the cup rinsed with 50 ml of water and taken orally. GT4P-F was stored at ambient temperature away from light.
GT4P-API was supplied as an odorless, colorless, tasteless oil in 125 ml bottles. The administered dose was calculated to contain the number of moles of PBA equivalent to 3 g/m2 of PBA. GT4P-API was taken orally and washed down with 100 ml of water. GT4P-API was stored at ambient temperature, away from light.
Ammonul® was supplied as single-use glass vials of 10% sodium phenylacetate and 10% sodium benzoate for intravenous injection. Ammonul® was diluted before use with sterile dextrose injection 10% to a concentration of 9 mg/ml. Once diluted it was kept at room temperature and used within 24 hours. The dose was 2.75 g/m2 and was administered as an intravenous infusion over a 120-minute period. Ammonul® was stored at 25°C, within a range of 15-30°C.
Sodium phenylbutyrate or Buphenyl® was supplied as a white powder in 250 g bottles. The required amount of powder (equivalent to 3 g/m2 of PBA) was weighed out, mixed in 100 ml of water, and administered orally. Doses were calculated on a weight/volume basis and corrected for sodium content and purity. Buphenyl® was stored at ambient temperature.
Inclusion Criteria: Subjects were required to fulfill the following criteria in order to participate in the study: Males aged 18 to 45 years of age Ability to provide written, informed consent before any study-related procedures, and ability, in the opinion of the investigator, to comply with all the requirements of the study Subjects who were in good health as determined by a medical history, physical examination, serum chemistry, hematology, urinalysis, 12 lead ECG, and vital signs Weight within the range of 60-120 kg Exclusion Criteria: Subjects who fulfilled any of the following criteria were excluded from the study: Clinically significant history or evidence of cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, neurologic, immunologic, or psychiatric disorder(s), as determined by the investigator Clinically significant abnormal laboratory values (as determined by the investigator) Significant illness within 14 days prior to screening Any disorder that might significantly interfere with the absorption, distribution, metabolism, or excretion of any drug Use of any prescription medication within 14 days prior to screening Use of dietary supplements, herbal medicines, vitamins, or over-the-counter medication(s) (with the exception of acetaminophen ≤ 500 mg/day) within 10 days prior to first dosing Positive drugs of abuse urine test at screening or pre-dose day (cocaine, amphetamines, barbiturates, opiates, benzodiazepines, cannabinoids, methadone) Positive alcohol breath test at screening or pre-dose day Donation or loss of blood (500 ml or more) within 30 days prior to first dosing, or during the study Donation or loss of plasma within 7 days prior to first dosing, or during the study History of or current hepatitis or carriers of hepatitis B surface antigen (HBsAg) and/or hepatitis C antibodies (anti-HC) History of acquired immunodeficiency syndrome (AIDS) or determined HIV positive at screening Use of any investigational drug within 12 weeks prior to first dosing Known hypersensitivity to sodium phenylbutyrate or similar drugs Previous exposure to sodium phenylbutyrate
