ClinicalTrials.gov record NCT04041713

A Pilot Study of an Antioxidant Cocktail vs. Placebo in the Treatment of Children and Adolescents With Rett Syndrome

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Jul 27, 2026

A Pilot Study of an Antioxidant Cocktail vs. Placebo in the Treatment of Children and Adolescents With Rett Syndrome

StatusRecruitingThe study is currently enrolling participants. Only the study team can say whether a particular person can join.
Study typeInterventionalA study in which researchers assign participants to one or more interventions, such as a drug, procedure, device, behavioural programme or other approach, to measure their effects.
PhasePhase 2A study that tests whether a treatment has the intended effect and continues to check safety, usually in a larger group than phase 1.
Age2 years old to 21 years old
SexFemale
LocationCanada
AI summaryWhat this study is about, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

This randomized, quadruple‑masked crossover study compares daily Rett‑T (an antioxidant powder) with matching placebo in females with Rett syndrome. Participants receive one treatment for 8 weeks, a 2‑week washout, then the other treatment for 8 weeks. The study measures motor function, behavior, sleep, seizures and safety, and will explore biological markers of safety and treatment response.

What it is studying. The study tests whether daily Rett‑T changes core motor function and is safe compared with placebo in children and adolescents with Rett syndrome, and it will explore biological markers linked to safety and treatment response.

What the researchers hope to learn. To assess whether Rett‑T affects motor function in Rett syndrome (primary outcome: Motor Behavior Assessment) and to evaluate safety and tolerability. Secondary goals include exploring effects on gross motor skills, maladaptive behaviors, anxiety, sleep, seizure measures, global clinical impression, caregiver top concerns, and biological markers of safety and response.

What this study is about

The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.

This study will examine the potential efficacy and safety of Rett-T for core motor deficits of Rett syndrome, and will explore biological markers of safety and treatment response.

Interventions being studied

Being studied in this trial does not mean the treatment or procedure is approved or available for this condition.

Drug
  • Rett-T
Other
  • Placebo

Eligibility

The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.

Inclusion criteria

  • Female outpatients 2-21 years of age inclusive.
  • Diagnosis of Rett syndrome.
  • At least partially ambulatory (may need assistive device to take a step).
  • If already receiving stable interventions must meet the following criteria:
  • If already receiving stable concomitant medications or nutraceuticals affecting behaviour, must be on a stable dose during the preceding 1 month prior to Screening (with the exception of fluoxetine, where a period of 6 weeks is needed), and will not electively initiate new or modify ongoing medications for study duration.
  • Have normal laboratory test results at Screening/Baseline. If abnormal, the finding(s) must be deemed clinically insignificant by the Investigator.
  • Ability to complete assessments, fluency in English (parent/legal guardian; participant, if verbal).
  • Ability to obtain assent (if developmentally appropriate), as well as written informed consent from their parent(s)/legal guardian(s).

Exclusion criteria

  • Pregnant females; sexually active females on inadequate birth control (extremely unlikely in this population).
  • Have another serious medical condition that, based on Investigator judgment, might interfere with the conduct of the study, confound interpretation of the study results, or endanger their own well-being. Have evidence or history of malignancy or any significant hematological, endocrine, cardiovascular (including any rhythm disorder), respiratory, renal, hepatic, or gastrointestinal disease, not including mild common pediatric diseases in these areas that are stable (e.g. mild asthma, constipation, etc.).
  • Have hypersensitivity to any components of Rett-T.
  • Have one or more of the following: HIV, HBV, HCV, hemophilia (bleeding problems, recent nose and brain injuries), drug abuse, immunity disorder, major depressive episode or psychosis.
  • Unable to tolerate venipuncture procedures for blood sampling.
  • Receiving concomitant medications/nutraceuticals that include any of the components of Rett-T.
  • Actively enrolled in another intervention study.

Study description and what participation involves

The study's detailed description, as published on ClinicalTrials.gov.

Detailed description from the registry

There are currently no available medicines shown to be effective for Rett syndrome. Numerous studies implicate mitochondrial dysfunction and oxidative stresses in the pathophysiology of Rett syndrome. Mitochondrial dysfunction has been reported in Rett patients, Rett mouse models and MECP2-deficient cells. Collaborators have tested a combination of specific antioxidants known to enhance mitochondrial function in a cell and mouse model of Rett syndrome. The formulation normalized mitochondrial membrane potential in MECP2 neurons, and MECP2-deficient mice displayed improved exploratory, locomotor and social behavior compared to MECP2-deficient mice. These results support testing anti-oxidative strategies for benefit in individuals with Rett syndrome.In this study, the formulation has been adjusted and optimized based on current guidelines for human use, with the goal of translating a potential new treatment from the animal model to use in humans. Results of this study could lead to the first approved medication treatment for the disorder.

AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

Participants are randomized and blinded to receive a daily oral powder (Rett‑T or placebo) for 8 weeks, then have a 2‑week washout, then receive the other product for 8 weeks (18 weeks total). Dose depends on weight (<30 kg: 4 g once daily; ≥30 kg: 8 g once daily) and the powder is dissolved in water. Study visits include motor function assessments and questionnaires about behavior, sleep and anxiety, safety monitoring (including blood draws), and tracking of seizures/symptoms; many study staff and participants will not know which product is given. Participants must keep stable medication/nutraceutical regimens during the study and avoid products containing components of Rett‑T.

How the study is structured. Participants are randomly assigned and blinded to receive either Rett‑T or a matching placebo as a daily oral powder (weight‑based dose: <30 kg = 4 g; ≥30 kg = 8 g) for 8 weeks, followed by a 2‑week washout, then 8 weeks on the alternate treatment (crossover). The study is quadruple‑masked (participant, care provider, investigator, outcomes assessor masked) and uses standardized motor and behavior scales plus safety monitoring over the 18‑week study period.

Questions you could ask

These questions are suggestions for a conversation with the study team or your own clinician, not advice.

  • Some participants receive a placebo. How is that decided, and what happens for placebo-group participants when the study ends?
  • The listed sites are in Canada. Is any of them reachable for me, and does the study help with travel?
  • Which of the eligibility criteria would need to be checked with tests before I could join?

More on Rett syndrome

Clinical trials20 trials listed for Rett syndromeEvery trial the registry lists for Rett syndrome, with recruitment status, phase and sites, updated from ClinicalTrials.gov.See all trials →Research updatesWhat changed in Rett syndrome researchLatest monthly update: September 2026. Includes: Seizure add-on drug. New research summarized each month in plain language, with links to every source paper.Read the latest update →

Important dates

Study start
Aug 24, 2026 (estimated)
Primary completion
Dec 30, 2027 (estimated)
Study completion
Dec 30, 2027 (estimated)
Target enrollment
35 participants (estimated)
Last updated on registry
Sep 2, 2026
Data verified
Oct 10, 2026

Sponsor and research team

The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.

Lead sponsor
Holland Bloorview Kids Rehabilitation Hospital
Collaborators
  • Ontario Brain Institute
  • Unity Health Toronto

Central study contact

If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.

Participating sites (1)

Terms used on this page · explanations by MedicalUpdates.ai

concomitant medications
Other medicines a participant takes during the study. Some must be reported; some are restricted.
stable dose
A dose that has not changed for a defined period before the study starts. Studies may require this so that background treatment is relatively stable when study measurements begin.
prior to Screening
The checks done before enrolment to see whether a person qualifies, such as tests, scans or a review of medical history.
Baseline
Measurements taken at the start of the study, before any study treatment, so that later results can be compared with them.
legal guardian
A person who is legally allowed to make decisions, including consent to research, on behalf of someone who cannot consent for themselves.
assent
A child's or dependent adult's agreement to take part, given alongside the formal consent of a parent or legal representative.
written informed consent
The process of explaining a study, including its risks and what participation involves, so that a person can decide freely whether to take part. Consent is usually documented in writing, and a participant can choose to leave the study later.
Inclusion Criteria
The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
Exclusion Criteria
The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.

The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.

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