Not recruiting

Study of KarXT (trospium chloride and xanomeline tartrate) in patients with inadequately controlled schizophrenia symptoms

Fast replyInvestigational

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What is this trial about?

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

This study focuses on people with schizophrenia who still experience symptoms despite taking their current medication. The research examines a new drug called KarXT, which contains two active substances: trospium chloride and xanomeline tartrate. KarXT will be tested as an additional treatment alongside existing medications for schizophrenia.

The purpose of this research is to determine if KarXT, when added to current schizophrenia treatment, can help reduce symptoms better than placebo. During the study, participants will continue taking their regular schizophrenia medication while also receiving either KarXT capsules or placebo capsules. The medication will be taken by mouth.

The study will last 6 weeks, during which the effectiveness of KarXT will be measured by tracking changes in schizophrenia symptoms. Throughout the study, participants will need to visit the clinic regularly for check-ups. The medication dose may be adjusted during the study period, with the highest possible daily dose being 310 milligrams.

The research process

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

Step 1
Initial evaluation
Your eligibility for the study will be assessed based on specific criteria, including age (18-65 years), current symptoms, and existing treatment regimen
You must have been taking a stable dose of one specific antipsychotic medication (risperidone, paliperidone, aripiprazole, ziprasidone, lurasidone, or cariprazine) for at least 8 weeks
Your PANSS total score (a measure of schizophrenia symptoms) must be 70 or higher
Step 2
Study medication period
The study will last 6 weeks
You will receive either KarXT capsules or placebo capsules (inactive substance) to take by mouth
You will continue taking your current antipsychotic medication throughout the study
Blood tests will be performed to confirm the presence of your regular antipsychotic medication in your system
Step 3
Regular assessments
Your symptoms will be evaluated using the PANSS scale (measures schizophrenia symptoms)
Your overall illness severity will be assessed using the CGI-S scale (measures illness severity)
Your daily functioning will be evaluated using the PSP scale (measures personal and social performance)
These assessments will occur throughout the study, with final measurements taken at week 6
Step 4
Study completion
The final evaluation will occur at week 6
The main goal is to measure the change in your PANSS total score from the beginning to the end of the study
Additional measurements will include changes in your daily functioning and overall illness severity

Who can join the trial?

12 criteria

Age between 18 and 65 years at the time of study entry
Must have a confirmed diagnosis of schizophrenia based on medical evaluation and confirmed through specialized psychiatric interview
Currently taking one of these medications at a stable dose for at least 8 weeks: risperidone, paliperidone, aripiprazole, ziprasidone, lurasidone, or cariprazine
Body Mass Index (BMI) must be between 18 and 40
Must have a stable living situation
Must have a reliable support person who can help with study activities
Must be able to visit the clinic regularly as an outpatient and follow study instructions
Must be able to understand and sign the informed consent form
Must have certain levels of symptoms as measured by specialized assessment tools (PANSS score of 70 or higher and CGI-S score of 4 or higher)
Must have detectable levels of current antipsychotic medication in their system
Must not have been hospitalized for psychiatric reasons or needed crisis intervention in the past 8 weeks
For women who can become pregnant and men with partners who can become pregnant: must agree to use effective birth control during the study and for 30 days after

Who cannot join the trial?

14 criteria

Current diagnosis of substance use disorder (addiction to drugs or alcohol) within the past 6 months
History of treatment-resistant schizophrenia (condition not improving with at least 2 different antipsychotic medications)
Presence of severe depression or thoughts of self-harm
Significant heart problems or abnormal heart rhythm
Unstable medical conditions that could affect study participation
Use of medications that could interact with the study drug
Pregnancy or breastfeeding
Participation in another clinical trial within the past 30 days
History of serious allergic reactions to similar medications
Inability to follow study procedures or provide informed consent
Severe cognitive impairment (significant problems with memory or thinking) that could interfere with assessments
History of violence or aggressive behavior in the past 6 months
Significant abnormal laboratory test results
Use of certain prohibited medications within 5 half-lives or 14 days before starting the study

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Verified sites

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

Medical Center Medconsult Pleven OOD
Verified
Pleven, Bulgaria
University Multiprofile Hospital For Active Treatment Saint Georgi EAD
Responsive
Plovdiv, Bulgaria

Trial locations

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Investigated drugs

KarXT is an investigational medication being studied as an add-on treatment for people with schizophrenia whose symptoms are not adequately controlled by their current medications. This medication works differently from existing antipsychotic treatments and aims to help reduce both positive symptoms (such as hallucinations and delusions) and negative symptoms (such as lack of motivation and social withdrawal) of schizophrenia.

What is already known about the treatment

KarXT - An investigational medication administered orally for the treatment of schizophrenia, particularly in patients whose symptoms are not adequately controlled by current treatments. It represents a novel approach to treating schizophrenia by targeting both muscarinic and nicotinic receptors in the brain, which differentiates it from traditional antipsychotic medications. This drug is currently being studied in Phase 3 clinical trials as an adjunctive (add-on) therapy for patients with schizophrenia who continue to experience symptoms despite their current treatment regimen. The medication aims to improve overall symptoms of schizophrenia as measured by the Positive and Negative Syndrome Scale (PANSS), which evaluates various aspects of the condition including positive symptoms (such as hallucinations) and negative symptoms (such as social withdrawal).

Investigated diseases

Schizophrenia - A chronic mental disorder that affects how a person thinks, feels, and behaves. It typically appears in late teens or early adulthood and is characterized by a combination of hallucinations, delusions, and disordered thinking and behavior. The condition often includes both positive symptoms (such as hearing voices or having false beliefs) and negative symptoms (such as reduced emotional expression or lack of motivation). People with schizophrenia may experience difficulties with memory, concentration, and social interactions. The condition varies in severity and presentation from person to person, with symptoms typically developing gradually over time.