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Study on Valbenazine for Patients with Schizophrenia Not Responding Well to Antipsychotic Treatment

Fast 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 the effects of a medication called Valbenazine on individuals with Schizophrenia. Schizophrenia is a mental health disorder that affects a person's ability to think, feel, and behave clearly. The study aims to evaluate how well Valbenazine works when used alongside other treatments for people who have not had enough improvement with their current antipsychotic medications.

Participants in the study will be randomly assigned to receive either Valbenazine or a placebo, which looks like the medication but does not contain the active ingredient. The study is designed to be double-blind, meaning neither the participants nor the researchers will know who is receiving the actual medication or the placebo. This helps ensure that the results are not influenced by expectations about the treatment. The study will last for a period of 10 weeks, during which participants will take the medication in capsule form by mouth.

The main goal of the study is to observe any changes in the symptoms of schizophrenia over the course of the treatment. Researchers will monitor participants' progress and gather data to determine the safety and effectiveness of Valbenazine as an additional treatment option for schizophrenia. The study will also assess how well participants tolerate the medication, looking at any side effects or other issues that may arise during the trial period.

The research process

The trial runs in 5 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 the diagnosis of schizophrenia and the current treatment regimen. This includes verifying the stability of the antipsychotic medication and ensuring that the symptoms meet the study criteria.

    A body mass index (BMI) check is performed, and for female participants, a pregnancy test is conducted to ensure eligibility.

  2. Step 2

    Baseline evaluation

    A baseline evaluation is conducted to record the initial Positive and Negative Syndrome Scale (PANSS) total score and the Clinical Global Impression of Severity (CGI-S) score. These scores help in assessing the severity of symptoms.

    The participant's current antipsychotic medication levels are measured to ensure they are within the required range.

  3. Step 3

    Randomization and treatment

    Participants are randomly assigned to receive either valbenazine or a placebo. The medication is administered in capsule form and taken orally.

    The dosage and frequency of administration are determined by the study protocol, and participants are required to adhere to the prescribed regimen for the duration of the study.

  4. Step 4

    Ongoing monitoring

    Throughout the study, participants attend regular visits to monitor their response to the treatment. This includes repeated assessments of the PANSS and CGI-S scores.

    Participants are also monitored for any side effects or changes in their condition.

  5. Step 5

    Final assessment

    At the end of the study period, a final assessment is conducted to evaluate changes in the PANSS and CGI-S scores from baseline to Week 10.

    The Personal and Social Performance Scale (PSP) score is also assessed to determine any improvements in personal and social functioning.

Who can join the trial?

15 criteria

  • Must have completed a written informed consent form, which is a document that explains the study and confirms your agreement to participate.
  • Your diagnosis of **schizophrenia**, current antipsychotic treatment, and symptom severity must be confirmed by the study team before starting the study treatment.
  • You need to have an adult informant, such as a family member, partner, or caregiver, who can provide information about you.
  • Your **body mass index (BMI)**, which is a measure of body fat based on height and weight, must be between 18.0 and 40.5.
  • If you are a female who can become pregnant, you must have a negative pregnancy test before starting the study and agree to use birth control during the study and for 30 days after.
  • Male participants must agree to use birth control during the study and for 30 days after the last dose of the study treatment.
  • You must be willing and able to follow all study procedures and restrictions, and the study team must believe you can do so.
  • You must be at least 18 years old at the time of signing the informed consent form.
  • You must have a medically confirmed diagnosis of **schizophrenia** according to specific guidelines and confirmed by a structured interview.
  • Your initial diagnosis of **schizophrenia** must have been made at least one year before the screening visit.
  • You must be receiving a stable dose of antipsychotic medication, other than clozapine, equivalent to 3 mg to 8 mg of risperidone daily.
  • Your blood levels of at least one antipsychotic medication must be detectable by a test.
  • You must have a stable treatment plan with antipsychotic medication.
  • You must meet specific criteria on certain scales that measure symptoms of **schizophrenia** at both the screening visit and the first day of the study.
  • You must be an outpatient, meaning you are not currently hospitalized, and your symptoms must be stable.

Who cannot join the trial?

7 criteria

  • Individuals who do not have a diagnosis of schizophrenia cannot participate. Schizophrenia is a mental health condition that affects how a person thinks, feels, and behaves.
  • Participants must be adults, as the study is not open to children or teenagers.
  • Both men and women can participate, but those who are pregnant or breastfeeding may be excluded for safety reasons.
  • Individuals who are unable to provide informed consent, meaning they cannot understand the study and agree to participate, are not eligible.
  • People who have a history of severe allergic reactions to the study medication or similar drugs cannot join the study.
  • Participants must not have any other serious medical conditions that could interfere with the study or put them at risk.
  • Individuals who are currently participating in another clinical trial may be excluded to avoid interference with the study results.
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Investigated drugs

Valbenazine is a medication being studied to see if it can help improve symptoms in people with schizophrenia who are not responding well to their current antipsychotic treatments. It is used as an additional treatment to see if it can provide better control of symptoms when combined with other antipsychotic medications.

What is already known about the treatment

Valbenazine – Valbenazine is administered orally in the form of capsules. It is currently being studied in clinical trials as an adjunctive treatment for schizophrenia, particularly for patients who do not respond adequately to standard antipsychotic medications. The medication works by selectively inhibiting vesicular monoamine transporter 2 (VMAT2), which reduces the release of dopamine in the brain, potentially helping to manage symptoms of schizophrenia. Valbenazine is classified as a vesicular monoamine transporter 2 inhibitor.

Investigated diseases

Schizophrenia – Schizophrenia is a chronic mental health disorder that affects how a person thinks, feels, and behaves. Individuals with schizophrenia may experience symptoms such as hallucinations, delusions, and disorganized thinking. These symptoms can lead to difficulties in distinguishing between what is real and what is not. The disorder often begins in late adolescence or early adulthood and can vary in severity. Over time, individuals may also experience reduced motivation, emotional flatness, and social withdrawal. The progression of symptoms can fluctuate, with periods of worsening and improvement.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-508433-14-00Protocol codeNBI-98854-ATS3019Estimated enrolment415 patientsSponsorNeurocrine Biosciences Inc.

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).