A Study of JNT-517 in Participants With Phenylketonuria (PKU)
Otsuka Pharmaceutical Development & Commercialization, Inc. · NCT06971731
Opens the official ClinicalTrials.gov record, with the study team’s contacts. Bored Studies doesn’t enroll anyone.
Key facts
- Compensation
- Not posted. Ask the study team before screening.
- Who can join
- Ages 4+ · All sexes
- Healthy volunteers
- Not accepted (a condition is required)
- Study type
- Interventional · Phase 3
- Target enrollment
- 120
- US sites recruiting
- 10
- Study start
- October 20, 2025
- Record last updated
- October 21, 2026
Status re-checked against ClinicalTrials.gov within the last 12 hours.
What the study is about
This Phase 3 study will evaluate the safety, effectiveness, tolerability, and how the body processes JNT-517 in children, adolescents, and adults with phenylketonuria.
Participants will be randomly assigned to receive either JNT-517 or placebo during an initial 6-week treatment period. After this period, eligible participants will receive JNT-517 for an additional 46 weeks.
Being studied: JNT-517; JNT-517 Matching Placebo
Conditions: Phenylketonuria
Eligibility criteria
Copied from the official record. The study team makes the final decision at screening.
Show full criteria
Inclusion Criteria
- Male or female participants aged 4 years or older.
- Diagnosed with phenylketonuria.
- Have phenylalanine levels that meet study requirements.
- Meet study-specific requirements regarding current treatment for phenylketonuria.
- Willing and able to follow study dietary requirements.
- Weigh at least 12.5 kilograms.
- If able to become pregnant or father a child, willing to follow the study's contraception requirements.
- Any ongoing mental health condition must be stable before entering the study.
- Able to provide informed consent (or have consent provided by a parent or legal guardian, when applicable) and comply with study procedures.
Exclusion Criteria
Participants will be excluded from the study if any of the following criteria are met:
- Significant medical condition that, in the investigator's opinion, could make participation unsafe or interfere with study participation.
- Significant liver disease or impaired kidney function.
- Certain eye conditions, including significant cataracts.
- Active infection requiring medical evaluation.
- History of certain cancers within the past 5 years.
- Allergy or hypersensitivity to JNT-517 or its ingredients.
- Prior treatment with JNT-517.
- Recent participation in another investigational study or receipt of an investigational treatment that does not meet study requirements.
- Use of medications that are not permitted during the study.
- Abnormal laboratory or heart test results that would make study participation inappropriate.
- Conditions that could affect the absorption of oral study medication.
- History of recent substance or alcohol abuse.
- Unwillingness to follow study requirements, including restrictions on intentional weight loss.
Recruiting US locations
University of California Los Angeles (UCLA) School of Medicine
Los Angeles, CA 90024
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
University of Florida (UF) Health Shands Hospital
Gainesville, FL 32608
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
University of South Florida
Tampa, FL 33606
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
Ann & Robert H. Lurie Children's Hospital of Chicago
Chicago, IL 60611
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
Oregon Health and Science University
Portland, OR 97239
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
University of Pittsburgh Medical Center (UPMC) - Children's Hospital of Pittsburgh
Pittsburgh, PA 15201
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
Vanderbilt University Medical Center
Nashville, TN 37232
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
University of Texas Southwestern
Dallas, TX 75390
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
University of Texas Health (UTHealth) Science Center at Houston
Houston, TX 77030-1501
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
Utah Health - The University of Utah Hospital
Salt Lake City, UT 84112
Site contact: Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com
Study contacts (from the official record)
- Otsuka Call Center · 844-687-8522 · Otsuka-ProfessionalServices@otsuka-us.com