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NCT05781399 · ClinicalTrials.gov registry record · Phase 1

First-in-Human, Multiple Part Clinical Study of JNT-517 in Healthy Participants and in Participants With Phenylketonuria

A Phase 1 study of Phenylketonuria, sponsored by Otsuka Pharmaceutical Development & Commercialization.

Active
Registry status
Phase 1
Development phase
135
Enrollment target
15
Study locations

NCT05781399: Active Phase 1 study of Phenylketonuria, sponsored by Otsuka Pharmaceutical Development & Commercialization.

NCT05781399 is a Phase 1 study of Phenylketonuria that is active but no longer recruiting, run by Otsuka Pharmaceutical Development & Commercialization. The registered enrollment target is 135 participants, above the 88-participant average among 12 other Phenylketonuria trials with a reported enrollment target (53% higher). The trial reports 15 study locations across 12 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT05781399, a Phase 1 study of Phenylketonuria, is active but no longer recruiting, sponsored by Otsuka Pharmaceutical Development & Commercialization.

ACTIVE NOT RECRUITING
Registry status
Phase 1
Development phase
135 participants
Enrollment target
15
Study locations

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.

Primary Outcome

Reported based on results of 12-lead ECGs, vital signs, clinical laboratory tests, and other medical assessments.

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

FieldValue
Enrollment Target 135 participants
Start Date 2022-10-31
Est. Completion 2025-12-15
Phase Phase 1

What the registry record for NCT05781399 still lists

NCT05781399 is an interventional study that assigns participants to a tested intervention. The registered 135 participants enrollment target is mid-sized for trials with a published cap, above the 88-participant average among 12 other Phenylketonuria trials with a reported enrollment target (53% higher).

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.

NCT05781399 lists 15 locations in 12 states (Florida, Pennsylvania, Texas).

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.

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).

Who is sponsoring clinical trial NCT05781399?

This trial is sponsored by Otsuka Pharmaceutical Development & Commercialization, which has 221 total clinical trials registered on ClinicalTrials.gov.

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.

Similar trials for Phenylketonuria

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT05781399's enrollment target sits among peer trials

135 4th of 12 higher than 9 of 12 other Phenylketonuria trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phenylketonuria trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT05781399, the US trial registry maintained by the National Library of Medicine. NCT05781399 (mid enrollment · multi site footprint · active not recruiting) retrieved and formatted by PlainTrial, see methodology.