A Phase 2 Study of JNT‑517 in Adolescent Participants With Phenylketonuria

Sponsor ID
JNT517-201
Clinicaltrials.gov ID
NCT06637514
EudraCT ID
N/A
EUCTIS ID
N/A
Sponsor
Otsuka Pharmaceutical Development & Commercialization, Inc.
Study Contact Information
N/A
Study Complete
Sponsor ID
JNT517-201
Trial Details
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Age
12 - 17 Years
Therapeutic Area
  • Phenylketonuria (PKU)
    • Sex
    Female & Male
    Trial Dates
    Jul 2025 - May 2026
    Healthy Volunteers
    No
    • Males and females 12 to less than 18 years of age, inclusive on Day 1.
    • Clinical diagnosis of PKU.
    • Ability to swallow tablets.
    • Average of 2 plasma Phe levels during the Screening period greater than 360 μM and no plasma Phe level less than 300 μM.
    • Body weight equal or greater than 45 kg and body mass index less than 40 kg/m2.
    • Females of childbearing potential must practice sexual abstinence or agree to use 2 highly effective contraceptive methods.
    • Capable of giving signed informed consent (emancipated minors) or parent/legal guardian to provide informed consent and the participant to give assent and confirm ability to comply with study procedures.
    • Any acute or chronic medical condition that would prevent the participant from complying with the procedures or place the participant at risk if they participate in the study.
    • Positive for hepatitis B or C or human immunodeficiency virus.
    • Any history of malignancy in the last 5 years, excluding nonmelanoma skin cancer.
    • Any history of liver disease.
    • Any history of cataracts or more than minimal cataracts observed during the Screening ophthalmologic examination.
    • Any surgical or medical conditions that may affect study drug absorption, distribution, metabolism, or excretion.
    • Creatinine clearance less than 90 mL/min by Cockcroft-Gault formula.
    • History of drug or alcohol abuse in the last year
    • Current, recent, or suspected infection within 14 days of Screening of SARS CoV 2/COVID 19.
    • Participation in another investigational drug trial within 30 days or, if known 5 half-lives of investigational drug (whichever is longer).
    • Unable to tolerate oral medication.
    • Allergy to JNT-517 or any component of the investigational product.
    • Received greater than 50 mL of blood or plasma within 30 days of Screening or greater than 500 mL of blood or plasma within 60 days of Screening.

    Study Summary

    The goal of this Phase 2, randomized study is to assess the safety, tolerability, and pharmacokinetics (PK) of oral JNT-517 in adolescents (12 to less than 18 years of age) with PKU. Participants will receive either JNT-517 or placebo and will be blinded to their treatment assignment. Participants will have a 4 in 5 (or 80%) chance of receiving JNT-517. The study will last for up to 63 days including a Screening period, Treatment period and Follow-up period for safety.

    Participants will:

    • Take 75 mg JNT-517 or a placebo BID (2x per day) for 28 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

    Additional Study Details

    Phase
    Phase 2
    Study Drug
    Drug: JNT-517 Tablet
    Type
    Interventional
    Masking
    Quadruple
    Estimated Enrollment
    14
    Additional Study Details

    Inclusion and Exclusion Criteria

    Inclusion Criteria

    • 1. Males and females 12 to less than 18 years of age, inclusive on Day 1.
    • 2. Clinical diagnosis of PKU.

    Exclusion Criteria

    • 1. Any acute or chronic medical condition that would prevent the participant from complying with the procedures or place the participant at risk if they participate in the study.
    • 2. Positive for hepatitis B or C or human immunodeficiency virus.
    Inclusion and Exclusion Criteria
    Inclusion Criteria:
    • Males and females 12 to less than 18 years of age, inclusive on Day 1.
    • Clinical diagnosis of PKU.
    • Ability to swallow tablets.
    • Average of 2 plasma Phe levels during the Screening period greater than 360 μM and no plasma Phe level less than 300 μM.
    • Body weight equal or greater than 45 kg and body mass index less than 40 kg/m2.
    • Females of childbearing potential must practice sexual abstinence or agree to use 2 highly effective contraceptive methods.
    • Capable of giving signed informed consent (emancipated minors) or parent/legal guardian to provide informed consent and the participant to give assent and confirm ability to comply with study procedures.
    Exclusion Criteria:
    • Any acute or chronic medical condition that would prevent the participant from complying with the procedures or place the participant at risk if they participate in the study.
    • Positive for hepatitis B or C or human immunodeficiency virus.
    • Any history of malignancy in the last 5 years, excluding nonmelanoma skin cancer.
    • Any history of liver disease.
    • Any history of cataracts or more than minimal cataracts observed during the Screening ophthalmologic examination.
    • Any surgical or medical conditions that may affect study drug absorption, distribution, metabolism, or excretion.
    • Creatinine clearance less than 90 mL/min by Cockcroft-Gault formula.
    • History of drug or alcohol abuse in the last year
    • Current, recent, or suspected infection within 14 days of Screening of SARS CoV 2/COVID 19.
    • Participation in another investigational drug trial within 30 days or, if known 5 half-lives of investigational drug (whichever is longer).
    • Unable to tolerate oral medication.
    • Allergy to JNT-517 or any component of the investigational product.
    • Received greater than 50 mL of blood or plasma within 30 days of Screening or greater than 500 mL of blood or plasma within 60 days of Screening.

    Locations

    Location
    Status
    Location
    University of Florida (UF) Health Shands Hospital
    Gainesville, Florida, United States, 32608
    Status
    N/A
    Location
    University of South Florida
    Tampa, Florida, United States, 33606
    Status
    N/A
    Location
    Oregon Health and Science University
    Portland, Oregon, United States, 97239
    Status
    N/A
    Location
    Children's Medical Center Dallas
    Dallas, Texas, United States, 75235
    Status
    N/A
    Location
    University of Texas Health (UTHealth) Science Center at Houston
    Houston, Texas, United States, 77030
    Status
    N/A
    Location
    Utah Health - The University of Utah Hospital
    Salt Lake City, Utah, United States, 84112
    Status
    N/A
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