Phenylketonuria (PKU)Phase 2CIPheRNCT07694440
A Study of MZE782 in Adults With PKU
A Phase 2 study testing MZE782 in people with Phenylketonuria (PKU), run by Maze Therapeutics at 9 sites in 3 countries.
Trial summary
The purpose of this study is to evaluate the safety, tolerability, and efficacy of MZE782 in adults with Phenylketonuria (PKU). Read more about this study
- Who is it for?
- Ages 18 to 75 years
- Conditions the study is for
- Phenylketonuria (PKU)
- What is being tested?
- MZE782
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 38 participants
- Where
- 9 sitesin 3 countries
- Study dates
- 23 Jun 2026to Feb 2028
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Males and females 18 to 75 years old
- Confirmed diagnosis of PKU
- Willing and able to keep diet and protein intake consistent during the study
- For some study groups, is willing and able to stop certain PKU medications before starting study treatment
- For some study groups, may need to meet additional blood phenylalanine level or background-treatment requirements
- Meets minimum blood phenylalanine level requirements for study group
Who cannot join
- Is pregnant, breastfeeding, or planning to become pregnant or conceive a child during the study
- Medical conditions or abnormal test results that could make participation unsafe or make it difficult to complete study procedures or interpret study results
- Has recently received another investigational drug
- Is unable to swallow tablets or tolerate oral medication
- Other inclusion/exclusion criteria defined in protocol apply.
Trial locations and contacts
9 sites in 3 countries. Contact the study team or a site near you to ask about taking part.
9 sites in 3 countries
United States7 sites, 7 recruiting
- Recruiting
Ann and Robert H. Lurie Children's Hospital of Chicago
Chicago, Illinois, 60611
- Recruiting
Clinic for Special Children
Gordonville, Pennsylvania, 17529
- Recruiting
Indiana University School of Medicine
Indianapolis, Indiana, 46202
- Recruiting
University of Kentucky Medical Center
Lexington, Kentucky, 40536
- Recruiting
University of Tennessee Health Science Center Le Bonheur Children's Hospital
Memphis, Tennessee, 38103
- Recruiting
UCSF Benioff Children's Hospital Oakland
Oakland, California, 94609
- Recruiting
Stanford University Clinical and Translational Research Unit
Palo Alto, California, 94304
France1 site, 1 recruiting
- Recruiting
CHRU Hôpitaux de Tours - Hôpital Bretonneau
Tours, 37044
United Kingdom1 site, 1 recruiting
- Recruiting
University College Hospital
London, NW1 2BU
About this study
Official title: A Phase 2, Randomized, Double-blind, Placebo-controlled, Dose-ranging Study to Evaluate the Safety, Tolerability, and Efficacy of MZE782 in Adults With Phenylketonuria (PKU)
The purpose of this study is to evaluate the safety, tolerability, and efficacy of MZE782 in adults with Phenylketonuria (PKU).
- Conditions
- Phenylketonuria (PKU)
- Being tested
- MZE782, Placebo
- Keywords
- PKU, Phenylketonuria
- Medical subject headings
- Phenylketonurias
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
MZE782Drug
Tablet, Low Dose
PlaceboOther
Tablet
MZE782Drug
Tablet, High Dose
| Study group | Role | What they receive |
|---|---|---|
| MZE782 Low Dose (Cohort 1A) | Experimental | Not described Receives: Drug: MZE782 |
| Placebo (Cohort 1A) | Placebo comparator | Not described Receives: Other: Placebo |
| MZE782 High Dose (Cohort 1B) | Experimental | Not described Receives: Drug: MZE782 |
| Placebo (Cohort 1B) | Placebo comparator | Not described Receives: Other: Placebo |
| MZE782 High Dose (Cohort 2) | Experimental | Not described Receives: Drug: MZE782 |
| Placebo (Cohort 2) | Placebo comparator | Not described Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Safety and tolerability based on incidence of adverse events (AEs)
Measured: Week 0 to Week 17
For Cohorts 1A and 1B: Absolute change in plasma Phe levels from Baseline to the mean of plasma Phe levels
Measured: Baseline and Weeks 2, 3, and 4
Secondary outcomes (3)
For Cohorts 1A and 1B, analyzed separately: Geometric mean plasma concentrations of MZE782
Measured: Weeks 1, 2, 3, 4, 8, and 13
For Cohorts 1A and 1B, analyzed separately: Absolute and Percent change in plasma Phe levels from Baseline to the mean of plasma Phe levels
Measured: Baseline up to Week 13
For Cohorts 1A and 1B, analyzed separately: Proportion of participants with mean plasma Phe levels ≤600 μMol/L, ≤360 μMol/L, and ≤120 μMol/L
Measured: Baseline and Weeks 2, 3, 4, 8, 10, and 13
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Jul 2026
- Study start23 Jun 2026
- Primary completionDec 2027 (estimated)
- Study completionFeb 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Phenylketonuria (PKU)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 38 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Maze Therapeutics
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Medical Director, Study director, Maze Therapeutics
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07694440
- Sponsor's protocol ID
- MZE782-201
- Acronym
- CIPheR
- Status last verified
- Oct 2026
- First submitted
- 2 Jul 2026
- Last updated
- 23 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No