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First-in-Human, Multiple Part Clinical Study of JNT-517 in Healthy Participants and in Participants With Phenylketonuria
NCT05781399 · View on ClinicalTrials.gov ↗
Study Summary
The goal of Parts A and B of this Phase 1/2, first-in-human, randomized study is to assess the safety, tolerability, and pharmacokinetics (PK) of single (SAD) and multiple (MAD) ascending doses of oral JNT-517 in healthy participants. In Part C, the goal is to evaluate the differences in bioavailability between a tablet and suspension formulation of JNT-517 and the food effect in healthy volunteers. All participants in Part C will receive JNT-517. The goal of Part D is to assess the safety, tolerability, PK, and effect on urinary Phe and other amino acids of JNT-517 in participants with phenylketonuria (PKU). Participants in Part D will receive either JNT-517 or placebo and will be blinded to their treatment assignment. The study consists of 6 parts: * Part A: SAD in healthy participants -randomized, double-blind, placebo-controlled * Part B: MAD in healthy participants (14 days)-randomized, double-blind, placebo-controlled * Part C: Relative bioavailability of 2 formulations and food effect in healthy participants-randomized, open-label * Part D: Phase 2 in participants with PKU (4 weeks)-randomized, double-blind, placebo-controlled * Part E: Phase 2 in participants with PKU (4 weeks) open label * Part F: SAD Phase 1 in healthy participants, randomized, double-blind, placebo-controlled In each part, participants will complete a Screening Period, a Treatment Period, and a Follow-up Period for safety.
Conditions Studied
Interventions
- DRUG JNT-517 Tablet
- DRUG Placebo Tablet
- DRUG JNT-517 Suspension
- DRUG Placebo Suspension
Study Locations (15)
Florida
- University of Florida College of Medicine — Gainesville
- University of South Florida — Tampa
Pennsylvania
- Children's Hospital of Philadelphia — Philadelphia
- UPMC Children's Hospital of Pittsburgh — Pittsburgh
Texas
- UT Southwestern Medical Center — Dallas
- University of Texas Health Science Center at Houston — Houston
Georgia
- Rare Disease Research — Atlanta
Illinois
- Ann & Robert H. Lurie Children's Hospital of Chicago — Chicago
Nebraska
- University of Nebraska Medical Center — Omaha
Oregon
- Oregon Health & Sciences University — Portland
Utah
- Utah Health - The University of Utah Hospital — Salt Lake City
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 135 participants |
| Start Date | 2022-10-31 |
| Est. Completion | 2025-12-15 |
| Phase | Phase 1 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT05781399
The ClinicalTrials.gov registry entry for NCT05781399 describes a study currently listed as active not recruiting. It is categorized as Phase 1, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 135 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Otsuka Pharmaceutical Development & Commercialization, which has 79 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 1 condition, with Phenylketonuria appearing as the primary indexed condition, and to 4 interventions — of which JNT-517 Tablet is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT05781399 reports 15 study locations spanning 12 distinct geographic areas — top geographies include Florida, Pennsylvania, Texas. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT05781399 about?
NCT05781399 is a clinical study titled "First-in-Human, Multiple Part Clinical Study of JNT-517 in Healthy Participants and in Participants With Phenylketonuria". The goal of Parts A and B of this Phase 1/2, first-in-human, randomized study is to assess the safety, tolerability, and pharmacokinetics (PK) of single (SAD) and multiple (MAD) ascending doses of oral JNT-517 in healthy participants. In Part C, the goal is to evaluate the differences in bioavailabi...
What is the current status of trial NCT05781399?
This trial is currently active not recruiting. It is a Phase 1 study. The enrollment target is 135 participants. The study started on 2022-10-31. Estimated completion is 2025-12-15.
What conditions does trial NCT05781399 study?
This clinical trial studies the following conditions: Phenylketonuria. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT05781399?
The interventions under investigation include: JNT-517 Tablet (DRUG), Placebo Tablet (DRUG), JNT-517 Suspension (DRUG), Placebo Suspension (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT05781399?
This trial is sponsored by Otsuka Pharmaceutical Development & Commercialization, which has 79 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT05781399 being conducted?
This trial has 15 study locations across Florida, Georgia, Illinois, Nebraska, Oregon. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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