Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Recruiting

A study testing direclidine compared to placebo in adults with schizophrenia who need hospital care

Fast replyInvestigationalNo placebo
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

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

This study is looking at schizophrenia, which is a mental health condition that affects how a person thinks, feels, and behaves. People with schizophrenia may experience symptoms such as hearing voices, having unusual beliefs, feeling confused, or having difficulty organizing their thoughts. The treatment being tested is called NBI-1117568, also known by its scientific name direclidine, which comes in capsule form and is taken by mouth. Some people in the study will receive the actual medication while others will receive a placebo.

The purpose of this study is to see if NBI-1117568 works better than placebo at improving the behavioral and psychological symptoms of schizophrenia in adults. The study will look at whether the medication can help reduce symptoms and improve the overall condition of people who are experiencing a sudden worsening of their schizophrenia symptoms that requires them to stay in the hospital. The study will also check how safe the medication is and whether people can tolerate it well.

People taking part in this study will be adults with schizophrenia who are currently in the hospital because their symptoms have gotten worse recently. The study will last for 5 weeks, during which time participants will take either NBI-1117568 or placebo capsules. Throughout the study, doctors will measure changes in symptoms using rating scales to see how well the treatment is working compared to placebo.

The research process

The trial runs in 4 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial hospitalization and baseline assessment

    Upon joining the study, you will be hospitalized as an inpatient. This hospitalization is necessary because your symptoms have suddenly worsened or returned within the last two months.

    During this initial phase, your condition will be assessed using standardized rating scales. The PANSS (Positive and Negative Syndrome Scale) will be used to measure the severity of your symptoms. This scale evaluates various aspects of your condition including positive symptoms (such as hallucinations or delusions), negative symptoms (such as reduced emotional expression), and general symptoms.

    Your overall illness severity will also be evaluated using the CGI-S (Clinical Global Impression-Severity) scale, which provides a general assessment of how severe your condition is at this starting point.

    These initial measurements will serve as the baseline to compare changes throughout the study.

  2. Step 2

    Treatment period with study medication

    You will be randomly assigned to receive either NBI-1117568 (the active study medication containing direclidine) or a placebo (an inactive capsule that looks identical to the active medication but contains no active substance).

    The study is double-blind, which means neither you nor your medical team will know which treatment you are receiving during the study period.

    You will take the assigned medication orally in the form of hard capsules.

    The treatment period will last for 5 weeks.

    Throughout this period, you will remain hospitalized so that your response to the treatment and any side effects can be closely monitored.

  3. Step 3

    Regular monitoring and assessments

    During the 5-week treatment period, your behavioral and psychological symptoms will be regularly evaluated.

    Your medical team will monitor your safety and how well you tolerate the study medication.

    Regular assessments will be conducted to track any changes in your symptoms and overall condition.

  4. Step 4

    Final assessment at week 5

    At the end of the 5-week treatment period, a final comprehensive assessment will be performed.

    The same rating scales used at the beginning (PANSS and CGI-S) will be used again to measure any changes in your symptoms compared to the baseline.

    The change in your PANSS total score from the beginning to week 5 will be the primary measure of whether the treatment was effective.

    The change in your CGI-S score from the beginning to week 5 will provide additional information about your overall improvement.

Who can join the trial?

4 criteria

  • You must be 18 years old or older and 65 years old or younger
  • You must have a main diagnosis of schizophrenia, which is a mental health condition that affects how a person thinks, feels, and behaves
  • You must be experiencing a sudden worsening or return of symptoms that started less than 2 months before the screening visit
  • Your current symptoms must be serious enough that you need to stay in a hospital for treatment

Who cannot join the trial?

10 criteria

  • The study does not include children or teenagers, only adults can participate
  • Patients who do not have a confirmed diagnosis of schizophrenia (a mental health condition that affects how a person thinks, feels, and behaves) cannot participate
  • People who are allergic or have had bad reactions to the study medication NBI-1117568 or similar medications cannot join
  • Patients who are currently participating in another clinical trial or have recently finished one may not be eligible
  • Women who are pregnant or breastfeeding cannot participate in this study
  • People with serious medical conditions affecting the heart, liver, kidneys, or other major organs may not be able to join
  • Patients with a history of drug or alcohol abuse within a recent period may be excluded
  • People who have attempted suicide recently or have active thoughts of harming themselves cannot participate
  • Patients taking certain medications that might interact with the study drug may not be eligible
  • People who cannot follow the study requirements or attend regular visits may be excluded
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

  • NBI-1117568

    is an investigational medication being studied for the treatment of schizophrenia. This medicine is being tested to see if it can help improve behavioral and psychological symptoms in adults with schizophrenia who need to stay in the hospital for treatment. The study will compare how well this medication works against a placebo to determine its effectiveness and safety.

  • Placebo

    is an inactive substance that looks like the real medication but contains no active medicine. It is used in this study to compare against the investigational medication to help researchers understand if the actual medication is working better than no treatment at all.

What is already known about the treatment

NBI-1117568 – NBI-1117568 is an investigational medication currently being studied in clinical trials for the treatment of schizophrenia in adults. This drug is being tested in hospitalized patients to see if it can improve behavioral and psychological symptoms associated with schizophrenia, such as hallucinations, delusions, and disordered thinking. The exact way this medication works in the body and its specific form of administration have not been publicly disclosed yet, as it is still in the research phase. This compound is being compared against placebo in a controlled study to determine whether it is safe, well-tolerated, and effective for managing symptoms of this serious mental health condition.

Investigated diseases

Schizophrenia – Schizophrenia is a chronic mental disorder that affects how a person thinks, feels, and behaves. People with this condition may experience distorted perceptions of reality, including hallucinations where they see or hear things that are not present, and delusions which are false beliefs. The disorder also causes disorganized thinking and speech, making it difficult for affected individuals to communicate clearly or follow logical thought patterns. Behavioral symptoms include reduced emotional expression, decreased motivation, and withdrawal from social activities. The condition typically emerges in late adolescence or early adulthood and tends to persist throughout life with varying levels of severity. Symptoms are generally categorized as positive symptoms such as hallucinations and delusions, negative symptoms such as reduced emotional response and social withdrawal, and cognitive symptoms affecting memory and attention.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2025-521215-39-00Protocol codeNBI-1117568-SCZ3030Estimated enrolment284 patientsSponsorNeurocrine Biosciences Inc.

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

ClinicalTrials.eu

Every clinical trial in Europe, in plain language.

Explore the full ecosystem of clinical research in Europe.

Search trials

Legal notice · Published by CTIN POLAND sp. z o.o., ul. rtm. Witolda Pileckiego 67/109, 02-781 Warsaw, Poland · KRS 0001111334 · REGON 528919042 · NIP 9512598637

© 2026 Clinical Trials EU – European Clinical Trials Information Network

GDPR compliance, ISO 9001 and ISO 27001 certified (LL-C Certification)

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).