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Study on the Effects of (+)-α-Dihydrotetrabenazine for Treating Tardive Dyskinesia in Patients with Schizophrenia, Mood, or Gastrointestinal Disorders

Verified siteFast replyInvestigationalNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying a condition known as tardive dyskinesia, which is a movement disorder that can occur in people who have been taking certain medications for mental health conditions. The trial will test a treatment called (+)-α-dihydrotetrabenazine, also known as (+)-α-DHTBZ, which is given as an oral solution. The purpose of the study is to evaluate how effective, safe, and tolerable this treatment is for people with tardive dyskinesia.

Participants in the study will receive different doses of the treatment to find the most effective and safe amount. The study will last for a period of eight weeks, during which participants will take the medication either once or twice a day. Throughout the study, participants will be monitored for any changes in their symptoms and any side effects they might experience. This will help researchers understand how well the treatment works and how it affects the body.

The study will also involve regular check-ups, including physical exams and tests to monitor participants' health. These tests will include assessments of movement symptoms, as well as checks on overall health, such as heart function and mental well-being. The information gathered from this study will contribute to understanding how (+)-α-DHTBZ can be used to help people with tardive dyskinesia manage their symptoms more effectively.

The research process

The trial runs in 7 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes a review of medical history and current health status.

    A urine drug screen and alcohol breath test are performed to ensure compliance with study requirements.

  2. Step 2

    Baseline evaluation

    A baseline evaluation is conducted to assess the severity of tardive dyskinesia (TD) symptoms using the AIMS Dyskinesia Total Score.

    Additional assessments may include the Clinical Global Impression of Tardive Dyskinesia (CGI-TD) and other scales to evaluate mental health and cognitive function.

  3. Step 3

    Medication administration

    The study involves the administration of (+)-α-dihydrotetrabenazine ((+)-α-DHTBZ) as an oral solution.

    Doses range from 10 to 20 mg once daily or 25 mg twice daily, depending on individual response and tolerance.

  4. Step 4

    Dose titration

    The dose of (+)-α-DHTBZ is adjusted over time to find the most effective and tolerable dose for each participant.

    Regular monitoring ensures safety and helps manage any side effects.

  5. Step 5

    Ongoing assessments

    Throughout the study, regular assessments are conducted to monitor the severity of TD symptoms and overall health.

    These assessments include the AIMS Dyskinesia Total Score, CGI-TD, and other relevant scales.

  6. Step 6

    Safety monitoring

    Safety is monitored through clinical evaluations, laboratory tests, and vital sign checks.

    Any adverse events are recorded and managed appropriately.

  7. Step 7

    Final evaluation

    At the end of the study, a final evaluation is conducted to assess the overall effectiveness and safety of the treatment.

    This includes a comparison of TD symptoms from baseline to the end of the study.

Who can join the trial?

11 criteria

  • Must be a male or female aged between 18 to 85 years old.
  • Should have good hearing, vision, and language skills to follow the study procedures.
  • Must have a negative urine drug test at the start of the study, except for those on a stable dose of certain medications. If positive for cannabinoids, the participant must agree to stop using them during the study. Also, must have a negative alcohol breath test at the start.
  • Must provide a signed and dated informed consent, which means agreeing to participate after understanding the study details.
  • Must have a clinical diagnosis of schizophrenia, schizoaffective disorder, mood disorder, gastrointestinal disorder (like gastroparesis or gastroesophageal reflux disease), and neuroleptic-induced tardive dyskinesia (TD) for at least 3 months before the study, with TD being moderate or severe.
  • Any medication for schizophrenia, schizoaffective disorder, mood disorders, or gastrointestinal disorders (except metoclopramide) must be at a stable dose for at least 30 days before the study.
  • If not using antipsychotic medication, must have a stable mental health status. Those with bipolar disorder must be on a stable dose of mood stabilizers (like lithium, valproate, or olanzapine) for at least 30 days before the study.
  • All medications and the conditions being treated must be stable for at least 30 days before the study and expected to remain stable during the study.
  • Participants who can have children must agree to use a highly effective method of birth control during the study.
  • Must be in good general health and expected to complete the study as planned.
  • Must have a body mass index (BMI) between 18 to 38 kg/m2.

Who cannot join the trial?

5 criteria

  • Patients who are not diagnosed with tardive dyskinesia. Tardive dyskinesia is a condition that causes involuntary movements, often due to long-term use of certain medications.
  • Patients who are not within the specified age range for the study. The study includes specific age groups, so those outside these groups cannot participate.
  • Patients who do not have schizophrenia, schizoaffective disorder, mood disorder, gastrointestinal disorder, or neuroleptic-induced tardive dyskinesia. These are specific conditions related to the study.
  • Patients who are not able to follow the study procedures or take the study medication as required.
  • Patients who are part of a vulnerable population that the study does not include. Vulnerable populations may include groups like children, pregnant women, or others who need special consideration.
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Investigated drugs

(+)-α-DHTBZ is being studied for its potential to treat tardive dyskinesia, a condition that causes involuntary movements. This medication is being tested to see how effective, safe, and tolerable it is for people with conditions like schizophrenia, schizoaffective disorder, mood disorders, gastrointestinal disorders, or tardive dyskinesia caused by other medications. The study is exploring different ways to take the medication, including once or twice a day.

What is already known about the treatment

(+)-α-DHTBZ – This medication is administered orally, with doses ranging from 10 to 20 mg taken once daily, or 25 mg taken twice daily. It is currently in a phase 2 clinical trial, focusing on its efficacy, safety, and tolerability for treating tardive dyskinesia, a movement disorder. The main therapeutic indication is for individuals with tardive dyskinesia, particularly those with schizophrenia, schizoaffective disorder, mood disorders, gastrointestinal disorders, or neuroleptic-induced tardive dyskinesia. At the molecular level, (+)-α-DHTBZ works by modulating neurotransmitter activity in the brain, which helps reduce involuntary movements. It is classified pharmacologically as a vesicular monoamine transporter 2 (VMAT2) inhibitor.

Investigated diseases

Tardive Dyskinesia – Tardive dyskinesia is a movement disorder characterized by involuntary, repetitive body movements. These movements often include grimacing, tongue movements, lip smacking, and rapid eye blinking. It can also affect the limbs and trunk, leading to jerky or writhing motions. The condition typically arises as a side effect of long-term use of certain medications, particularly antipsychotics. Symptoms may vary in intensity and can sometimes be subtle, making them difficult to detect in the early stages. Over time, the movements can become more pronounced and persistent.
Trial detailsLast updated 22 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-519105-35-00Protocol code2022-01Estimated enrolment6 patientsSponsorAdeptio Pharmaceuticals Limited

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