A Long-Term Safety Study of PTC923 in Participants With Phenylketonuria
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Phase
Phase 3
Status
Active, not recruiting
Study type
Interventional
Design
Na · None · Treatment
Enrollment
200estimated
Sites
46
Countries
Australia, Brazil, Canada +16
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2022-02-14 | actual | When the study began enrolling |
| Primary completion | 2026-06-30 | estimated | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2026-06-30 | estimated | The whole study's end, after follow-up |
| First posted | 2021-12-21 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-06-23 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Phenylketonuria
Intervention
- Drug: PTC923 — also filed as Sepiapterin, Sephience
Primary outcomes
what the primary-completion date above is the date OFNumber of Treatment-Emergent Adverse Events (TEAEs)
measured Baseline up to end of study (up to 4 years)
Change From Baseline in Dietary Phe/Protein Consumption at Week 26, Measured During Phe Tolerance Assessment Period
measured Baseline, Week 26
Publications
- PMID 41537382 — linked by the registry
Linked on the registry record. A “linked by the registry” entry is NLM's own automated PubMed match, not a claim by the sponsor that the paper reports this study.
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