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Study on Vafidemstat for Treating Negative Symptoms and Cognitive Impairment in Adults with Schizophrenia

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 new treatment for schizophrenia, a mental health condition that affects how a person thinks, feels, and behaves. The treatment being tested is a medication called vafidemstat, which is taken in the form of capsules. The study will compare the effects of vafidemstat to a placebo, which looks like the medication but does not contain any active ingredients.

The purpose of the study is to evaluate how well vafidemstat works in reducing negative symptoms and improving cognitive function in people with schizophrenia. Negative symptoms can include things like lack of motivation, reduced emotional expression, and social withdrawal, while cognitive impairment refers to difficulties with memory, attention, and problem-solving. Participants in the study will be randomly assigned to receive either vafidemstat or the placebo, and neither the participants nor the researchers will know who is receiving which treatment.

The study will last for 24 weeks, during which participants will take the capsules regularly and attend scheduled visits with the research team. These visits will help monitor the participants' progress and any changes in their symptoms. The study aims to provide valuable information about the potential benefits of vafidemstat for individuals living with schizophrenia.

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

    Joining the study

    Upon joining the study, you will be assigned to one of two groups: one receiving the vafidemstat medication and the other receiving a placebo. A placebo is a capsule that looks like the medication but contains no active ingredients.

    The study is designed to be 'double-blind,' meaning neither you nor the study team will know which group you are in. This helps ensure the results are unbiased.

  2. Step 2

    Medication administration

    You will take the assigned capsules orally. The dosage and frequency will be determined by the study protocol, and you will be informed of these details at the start of the trial.

    The duration of the medication administration is planned for 24 weeks.

  3. Step 3

    Regular study visits

    Throughout the study, you will attend regular visits to monitor your health and the effects of the medication. These visits will include assessments of your symptoms and overall well-being.

    Your study partner or caregiver should accompany you to these visits to provide additional information about your cognitive and functional abilities.

  4. Step 4

    Safety and efficacy assessments

    The study will evaluate the change in your symptoms using various scales and assessments, such as the PANSS (Positive and Negative Syndrome Scale) and the BACS (Brief Assessment in Cognition in Schizophrenia).

    Safety will be monitored by tracking any adverse events or changes in your health status throughout the study period.

  5. Step 5

    End of study procedures

    At the end of the 24-week period, you will undergo final assessments to evaluate the overall impact of the treatment.

    You will be informed about the next steps and any follow-up procedures that may be necessary.

Who can join the trial?

16 criteria

  • Participant must be a male or female aged between 18 and 55 years.
  • Participant should be healthy and medically stable based on their medical history, physical exams, and lab tests.
  • Participant must be able to read and write fluently and have good hearing and vision to complete the study tests.
  • Participant must have a negative Covid-19 test if Covid-19 precautions are still in place during the screening visit.
  • Participant needs a study partner or caregiver who spends at least 4 hours a week with them and can attend study visits. This person must also provide consent.
  • Participant must have a stable living environment for more than 6 months before the screening visit, confirmed by the study partner or caregiver.
  • If the participant is fertile, they must use highly effective contraception from the screening visit until 30 days after the last dose of the study medication.
  • Female participants who can have children must have a negative pregnancy test at screening and baseline.
  • Participant and their study partner or caregiver must provide signed informed consent and be able to understand and follow study requirements.
  • Participant must have schizophrenia as confirmed by a specific interview and meet the diagnostic criteria for more than one year.
  • Participant must have persistent negative symptoms of schizophrenia with minimal positive symptoms, as measured by specific scales during screening and baseline.
  • Participant must be stable in terms of symptoms of schizophrenia over the last 3 months, according to their psychiatrist and medical records.
  • Participant should be an outpatient or in day treatment with stable symptoms for at least 3 months before the screening visit, with no recent hospitalizations or changes in medication.
  • Participant must have a stable medication regimen for at least 3 months and agree to inform the study doctor of any medication changes during the trial.
  • Participant's body mass index (BMI) should be between 18.5 and 35 kg/m² at screening. Those with a BMI between 35 and 40 kg/m² will be reviewed for safety and may need special approval.
  • Participant must be considered reliable and willing to follow the study rules and requirements.

Who cannot join the trial?

3 criteria

  • Patients who do not have a diagnosis of schizophrenia.
  • Patients who are not adults. This means anyone under the age of 18.
  • Patients who are part of a vulnerable population. This generally includes groups like pregnant women, prisoners, or those unable to give consent.
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Investigated drugs

Vafidemstat is a medication being studied for its potential to help with certain symptoms of schizophrenia. Schizophrenia is a mental health condition that can cause a range of symptoms, including negative symptoms like lack of motivation or interest in activities, and cognitive impairment, which affects thinking and memory. Vafidemstat is being tested to see if it can improve these specific symptoms in people with schizophrenia. The trial aims to find out if this medication can make a positive difference in the lives of those affected by these challenging symptoms.

What is already known about the treatment

Vafidemstat – Vafidemstat is administered orally in the form of a tablet. It is currently being studied in clinical trials for its potential use in treating schizophrenia, specifically targeting negative symptoms and cognitive impairment. The medication works by modulating certain enzymes in the brain, which may help improve mood and cognitive functions. Vafidemstat is classified as a psychiatric medication, and its primary therapeutic indication is for schizophrenia.

Investigated diseases

Schizophrenia – Schizophrenia is a chronic mental health disorder characterized by disruptions in thought processes, perceptions, emotional responsiveness, and social interactions. It typically manifests with symptoms such as hallucinations, delusions, disorganized thinking, and significant impairments in daily functioning. The disease progresses with episodes of psychosis, where individuals may lose touch with reality, interspersed with periods of more stable functioning. Negative symptoms, such as reduced emotional expression and lack of motivation, can become more prominent over time. Cognitive impairments, including difficulties with memory, attention, and problem-solving, may also develop and persist. The course of schizophrenia varies among individuals, with some experiencing a gradual worsening of symptoms, while others may have periods of improvement.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-507372-42-00Protocol codeCL09-ORY-2001Estimated enrolment239 patientsSponsorOryzon Genomics S.A.

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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).