A Study of PTC923 in Participants With Phenylketonuria

Recruiting in Palo Alto (17 mi)

+47 other locations

Age: Any Age

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 3

Waitlist Available

Sponsor: PTC Therapeutics

Pivotal Trial (Near Approval)

Prior Safety Data

Approved in 2 jurisdictions

Trial Summary

What is the purpose of this trial?This trial is testing a medication called PTC923 to see if it can lower blood phenylalanine levels in people with phenylketonuria (PKU). PKU patients have trouble breaking down phenylalanine, which can lead to health issues. The study will measure how well PTC923 works by comparing blood phenylalanine levels over time.

Eligibility Criteria

Inclusion Criteria

Uncontrolled blood Phe level ≥360 μmol/L on current therapy anytime during screening and uncontrolled blood Phe level ≥360 μmol/L on current therapy when taking the average of the 3 most recent Phe levels from the participant's medical history (inclusive of the screening value).

Clinical diagnosis of phenylketonuria with hyperphenylalaninemia (HPA) documented by past medical history of at least 2 blood Phe measurements ≥600 μmol/L.

You are male and you are sexually active with women of childbearing potential

+2 more

Participant Groups

3Treatment groups

Experimental Treatment

Placebo Group

Group I: Part 2: PTC923Experimental Treatment1 Intervention

Participants will receive PTC923 20 mg/kg daily for Weeks 1 and 2, then PTC923 40 mg/kg daily for Weeks 3 and 4, then PTC923 60 mg/kg daily for Weeks 5 and 6.

Group II: Part 1: PTC923Experimental Treatment1 Intervention

Participants will receive PTC923 7.5 milligrams (mg)/kilogram (kg) (participants 0 to \<6 months of age), 15 mg/kg (participants 6 to \<12 months of age), 30 mg/kg (participants 12 months to \<2 years of age), or 60 mg/kg (participants ≥2 years of age) orally once daily for 14 days.

Group III: Part 2: PlaceboPlacebo Group1 Intervention

Participants will receive equivalent quantities of placebo to match the 20 to 40 to 60 mg/kg dose escalation of the PTC923 treatment arm.

PTC923 is already approved in United States, European Union for the following indications:

🇺🇸 Approved in United States as PTC923 for: