A Study of JNT-517 in Participants With Phenylketonuria (PKU) (NCT06971731)
A Phase 3, Double-Blind, Randomized, Two-Period, Multicenter, Placebo-Controlled, Efficacy and Safety Study of JNT-517 for the Treatment of Participants With Phenylketonuria
🩺 Plain-English Summary (8th-Grade Level)
The goal of this Phase 3, randomized study is to assess the safety, efficacy, tolerability, and pharmacokinetics (PK) of oral JNT-517 in adults (18 years of age or older) with PKU. Participants will receive either JNT-517 or placebo and will be blinded to their treatment assignment. Participants will have a 2 in 3 (or approximately 67%) chance of receiving JNT-517 during the first part of the study which will last approximately six weeks. During the second part of the study every participant who continues in the study will receive one of two doses of JNT-517 for an additional 46 weeks. The study requires a screening period of up to 35 days to ensure dietary stabilization and amino acid levels required to meet study eligibility. In total, participation in the study could last for up to 400 days. Participants will: Take 75 mg JNT-517 or 150 mg JNT-517, or a placebo BID (2x per day) for approximately 365 days; Visit the clinic or have a mobile health nurse visit your home for checkups and tests; Collect urine sample at home and bring to clinic on specified days; Keep a food diary 3 days before each study visit
Who can join: Review the eligibility criteria below.
Location: University of California Los Angeles (UCLA) School of Medicine — Los Angeles, California
Age range: 18 Years
🧪 Interventions in This Study
📋 "Do I Qualify?" — 1-Minute Self Screener
Instant ChecklistFull eligibility criteria are available on the official NIH protocol. View the criteria ↗
📍 All Participating Trial Locations (26 Sites)
Showing the first 25 of 26 sites.
- University of California Los Angeles (UCLA) School of Medicine — Los Angeles, California
- University of Florida (UF) Health Shands Hospital — Gainesville, Florida
- University of South Florida — Tampa, Florida
- Ann & Robert H. Lurie Children's Hospital of Chicago — Chicago, Illinois
- Oregon Health and Science University — Portland, Oregon
- University of Pittsburgh Medical Center (UPMC) - Children's Hospital of Pittsburgh — Pittsburgh, Pennsylvania
- Vanderbilt University Medical Center — Nashville, Tennessee
- University of Texas Southwestern — Dallas, Texas
- University of Texas Health (UTHealth) Science Center at Houston — Houston, Texas
- Utah Health - The University of Utah Hospital — Salt Lake City, Utah
- Royal Adelaide Hospital — Adelaide,
- Royal Melbourne Hospital — Parkville,
- Mater Health - Mater Hospital Brisbane — South Brisbane,
- M.A.G.I.C Clinic — Calgary, Alberta
- Fakultní nemocnice Královské Vinohrady — Prague,
- Centre Hospitalier Régional Universitaire (CHRU) de Tours - Hôpital Bretonneau — Tours,
- Universitaetsmedizin der Johannes Gutenberg-Universitaet Mainz — Mainz,
- Universitätsklinikum Münster — Münster,
- Nihon University Hospital — Chiyoda-ku,
- Fujita Health University — Kutsukake-cho,
- Osaka Metropolitan University Hospital — Osaka,
- Universitair Medisch Centra (AMC)- Amsterdam — Amsterdam,
- Beatrix Children's Hospital — Groningen,
- Pomorski Uniwersytet Medyczny w Szczecinie — Szczecin,
- Hospital Universitario Ramón y Cajal — Madrid,
📞 Contact the Study Coordinator
Phone: (844) 687-8522
Email: otsuka-professionalservices@otsuka-us.com
Coordinator details come directly from the registered NIH protocol. Confirm the study is still recruiting before traveling.
💰 Cost, Insurance & Patient Rights
- 100% Free Items: The investigational treatment and protocol-required procedures are supplied at zero cost by the sponsor.
- Routine Patient Care: Under federal law (ACA § 2709) and many state statutes, routine care costs are covered during participation.
- Voluntary Participation: You may withdraw at any time without affecting your standard medical care.
More studies in Phenylketonuria
- A Long-Term Safety Study of PTC923 in Participants With Phenylketonuria — Aurora, Colorado
- Rapid Drug Desensitization Study in Adults Experiencing Hypersensitivity Reactions to Palynziq — Chevy Chase, Maryland
- A Phase 1/Phase 2 Open-label Study to Evaluate the Safety, Tolerability, and Efficacy of a Single Intravenous Administration of SAR444836 in Adult Participants With Phenylketonuria — San Francisco, California
- Immune Modulation During Palynziq® Treatment in Adults (IMPALA) — Los Angeles, California
- A Study to Evaluate Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of AG-181 in Subjects With Phenylketonuria — Indianapolis, Indiana
Explore by condition: All Phenylketonuria clinical trials
💡 How to Participate
- Check the checklist above to see if you may qualify.
- Contact the study coordinator using the phone/email above.
- Ask about the visit schedule, what is covered at no cost, and any travel support.
- Confirm with your own doctor before making a decision.