NCT05166161Phase 3Completed

A Long-Term Safety Study of PTC923 in Participants With Phenylketonuria

Compare the available registry edits below. Primary completion is the date data collection ends for the main study measures; it does not tell you when results will be published.

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Primary completion2026-07-21Actual

Enrollment · participants247Actual

Source updated2026-09-09Last update listed in the registry record

Version history

Changes to this trial

Last 12 months

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Posted 2026-09-09 · 5 fields changed

Participant count type changed

− Before

~~Estimated~~

+ After

Actual

Enrollment · participant count changed

− Before

~~200 participants (planned)~~

+ After

247 participants (actual)

Completion date type changed

− Before

~~Estimated~~

+ After

Actual

Primary completion date changed

− Before

~~30 Jun 2026~~

+ After

21 Jul 2026

Recruitment status changed

− Before

~~Active not recruiting~~

+ After

Completed

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Posted 2026-02-10 · 2 fields changed

Primary completion date changed

− Before

~~30 Apr 2026~~

+ After

30 Jun 2026

Recruitment status changed

− Before

~~Recruiting~~

+ After

Active not recruiting

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Study details

Conditions studied

Phenylketonuria

Treatments or interventions studied

PTC923DrugAlso known as Sepiapterin, Sephience

Primary outcomes · main study measures

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measure: Number of Treatment-Emergent Adverse Events (TEAEs); description: A TEAE is any unfavorable or unintended sign (including an abnormal laboratory finding), symptom or disease in a study participant who is administered study drug in this study; timeFrame: Baseline up to end of study (up to 4 years); measure: Change From Baseline in Dietary Phe/Protein Consumption at Week 26, Measured During Phe Tolerance Assessment Period; description: Phe tolerance is defined as the total amount of dietary Phe (milligrams \[mg\]/kilogram \[kg\] per day) ingested while maintaining blood Phe levels within the range of 40 to 360 micromoles (μmol)/liter (L) (defined as ≥40 to \<360 μmol/L).; timeFrame: Baseline, Week 26

History coverage

Research sample: selected versions from May 2023 onward plus a preceding baseline where available. Only selected fields were retained; endpoint measures were truncated to 300 characters. This is not complete trial or sponsor history. Daily snapshots begin when collection starts.

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