Skip to content

Study Details

Testing the Drug PTC923 (Sepiapterin) in People with Phenylketonuria

(IRB#: IRB_00150586)

Phenylketonuria (also called PKU) is a condition in which your body can't break down an amino acid called phenylalanine. This study will test a drug called PTC923 (Sepiapterin) to treat people with Phenylketonuria. The study wants to understand the long-term safety in patients with PKU and changes in diet. People in this study will be placed into two groups depending on their blood phe levels to be treated with PTC923 (Sepiapterin). The drug is taken as a swallowed pill. Being in the study may require about 15 visits at the study clinic and some may be virtual visits on the phone. This is determined by participants' assigned groups. Medical tests will be done during the study to track the health of participants.


  • All genders
  • All Ages
  • Volunteers with special conditions
  •   In Person
  • Paid

Who can participate?

 Gender: All genders

  Age: All Ages

  Volunteers: Volunteers with special conditions

   Location: In Person

Inclusion Criteria

  • Ages 0 years old and above
  • Clinical diagnosis of PKU with at least 2 high blood Phe levels
  • Willing to continue current diet unchanged while participating in the study
  • Participants of childbearing age willing to use birth control
  • Able to attend in person clinic visits

Exclusion Criteria

  • Unable to take swallow medication
  • Pregnant, breastfeeding, or considering pregnancy
  • Have a serious mental illness such as major depression
  • Past medical history and/or evidence of renal impairment or renal insufficiency (kidneys do not function properly)
  • Treatment with tetrahydrobiopterin (BH4) supplementation (eg, sapropterin dihydrochloride, KUVAN) or pegvaliase-pqpz (PALYNZIQ).

Will I be paid for my time?


For more information contact:

Carrie Bailey


IRB#: IRB_00150586

PI: Ashley Andrews


Approval Date: 2023-01-04 07:00:00

Specialties: Pediatric Genetics

Last Updated: 6/8/23