5102: A Randomized, Double-Blind, Crossover Study of Sodium Phenylbutyrate (Buphenyl™) and Low-Dose Arginine (100 mg/kg/day) Compared to High-Dose Arginine (500mg/kg/day) Alone on Liver Function, Ureagenesis and Subsequent Nitric Oxide Production in Patients with Argininosuccinic Aciduria (ASA)

Status: Not recruiting at this time


About this Study

This is a study to determine if treatment of argininosuccinic aciduria (ASA) patients with sodium phenylbutyrate (Buphenyl TM) along with low arginine improves outcomes. Our goal is to study 12 participants with ASA. Unlike the other urea cycle disorders, ASA can lead to serious liver damage. The cause of this liver damage is not known, but since high levels of argininosuccinic acid are found in this disease and not in the other urea cycle disorders, doctors suspect this may be the cause of the liver damage.

Through this study we hope to learn how the use of sodium phenylbutyrate (Buphenyl-TM) and low dose arginine, along with a restricted-protein diet, affects liver activity in patients with ASA. We will also study how this treatment compares to therapy with high-dose arginine alone in affecting how well an individual with ASA is able to change nitrogen into nitric oxide and urea. Our goal is to help doctors and researchers find out more about how to best treat individuals with ASA.

Those participating will be evaluated during two separate in-patient visits conducted at Texas Children's Hospital in Houston, Texas.


Target Enrollment

To be eligible to participate, you must:

  • Weigh at least 10 kg (22 pounds) and be able to perform study procedures such as urine collection. Must have a confirmed diagnosis of ASA.
  • Agree to travel to Baylor College of Medicine in Houston, Texas.
  • Maintain the diet and treatment plan prescribed by Dr. Brendan Lee while you are in the study

You are not eligible to participate if:

  • Has a history of congestive heart failure, severe renal insufficiency, or any condition that causes sodium retention or edema.
  • Currently taking Probenecid, Haloperidol, Valproate or oral Corticosteroids.
  • Is pregnant or lactating.
  • Is currently being treated for an acute illness.
  • Has co-morbid associations causing difficulties in the detection of hyperammonemic episodes, liver damage or difficulties in the diet compliance.
  • Has known hypersensitivity to sodium phenylbutyrate.
  • Has taken any experimental medication within the last 30 days.
  • Has renal insufficiency with creatinine > 1.5 mg/dl at screening.

Total Enrolled