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Study on the Effectiveness of Aripiprazole and Paliperidone in Patients Experiencing Their First Episode of Schizophrenia

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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 treatment of patients experiencing their first episode of schizophrenia or related conditions, such as treatment-resistant schizophrenia. The study will compare the effectiveness and safety of two medications: Aripiprazole (known as Abilify Maintena) and Paliperidone (known as Xeplion). These medications are given as injections that release the drug slowly over time.

The purpose of the study is to use advanced techniques to identify biological markers that can predict how well a patient will respond to these treatments. Patients will receive either Aripiprazole or Paliperidone for a period of up to one year. The study will monitor changes in symptoms and overall health at three and twelve months to determine the effectiveness of the treatments. The study will also look at how long patients continue with their initial treatment and any side effects they may experience.

Throughout the study, various aspects of the patients' health will be assessed, including changes in symptoms, quality of life, and any side effects. The study aims to provide a better understanding of how these medications work in treating schizophrenia and related conditions, ultimately helping to improve treatment strategies for these patients.

The research process

The trial runs in 6 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 verifying age (15-40 years), residence in the area, and diagnosis of a first psychotic episode within the schizophrenia spectrum.

  2. Step 2

    Treatment assignment

    Participants are randomly assigned to receive either aripiprazole or paliperidone. These medications are administered as prolonged-release injections.

  3. Step 3

    Medication administration

    The medication is given as an injection. Aripiprazole is provided as 'Abilify Maintena 300 mg', and paliperidone as 'Xeplion 150 mg' or 'Xeplion 100 mg'. The injections are administered at regular intervals as determined by the study protocol.

  4. Step 4

    Three-month evaluation

    After three months, the effectiveness of the treatment is evaluated. This involves assessing changes in psychotic symptoms using specific scales designed to measure symptom severity and response to treatment.

  5. Step 5

    Ongoing monitoring

    Participants continue to receive their assigned medication and are monitored for changes in symptoms, side effects, and overall health. Evaluations occur at three and twelve months, focusing on symptom changes, side effects, and quality of life.

  6. Step 6

    Final assessment

    At the end of the study period, a final assessment is conducted to evaluate the long-term effectiveness of the treatment. This includes measuring the time to discontinuation of the medication and overall treatment response.

Who can join the trial?

4 criteria

  • Patients must be between 15 and 40 years old.
  • Patients should live in the area where the study is being conducted.
  • Patients must be experiencing their first psychotic episode. A psychotic episode is a period when a person has trouble distinguishing between what is real and what is not.
  • Patients must have a diagnosis within the schizophrenia spectrum according to the DSM-5. This includes conditions like schizophreniform disorder (a condition similar to schizophrenia but shorter in duration), schizophrenia (a mental disorder affecting how a person thinks, feels, and behaves), schizoaffective disorder (a condition featuring symptoms of both schizophrenia and mood disorder), brief psychotic disorder (a short-term condition with sudden onset of psychotic symptoms), or psychotic disorder not otherwise specified (a condition with psychotic symptoms that do not fit other specific categories).

Who cannot join the trial?

6 criteria

  • Patients who have not experienced a first psychotic episode. A psychotic episode is a period when a person loses touch with reality, which can include seeing or hearing things that aren't there or having unusual thoughts.
  • Patients who do not have schizophrenia. Schizophrenia is a mental health condition that affects how a person thinks, feels, and behaves.
  • Patients who do not have treatment-resistant schizophrenia. This means that the usual treatments for schizophrenia have not been effective for them.
  • Patients who are not within the specified age range for the study.
  • Patients who are not willing or able to follow the study procedures.
  • Patients who are part of a vulnerable population, which means they might need special protection or care.
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Investigated drugs

  • Aripiprazole

    is a medication used to treat certain mental health conditions, such as schizophrenia. It helps to restore the balance of certain natural chemicals in the brain, which can improve mood, behavior, and thinking. In this trial, aripiprazole is being evaluated for its effectiveness in reducing symptoms in patients experiencing their first episode of psychosis.

  • Paliperidone

    is another medication used to treat schizophrenia and similar mental health conditions. It works by helping to balance the chemicals in the brain, which can help reduce symptoms like hallucinations and improve overall mental function. This trial is assessing how well paliperidone works in patients who are experiencing their first psychotic episode.

  • Risperidone

    is a medication that is also used to treat schizophrenia and other mental health disorders. It helps to manage symptoms by affecting the activity of certain neurotransmitters in the brain. In this study, risperidone is being compared to other treatments to see how effective it is for patients with a first episode of psychosis.

What is already known about the treatment

  • Aripiprazole

    Aripiprazole is administered orally in tablet form and is currently used in the treatment of schizophrenia and related psychotic disorders. It is well-documented in medical literature as an effective antipsychotic, particularly for patients experiencing their first psychotic episode or those with treatment-resistant schizophrenia. Aripiprazole works by modulating dopamine and serotonin receptors in the brain, helping to balance neurotransmitter activity. It is classified as an atypical antipsychotic, known for its ability to reduce symptoms of psychosis with a lower risk of certain side effects compared to older antipsychotics.

  • Paliperidone

    Paliperidone is available in extended-release tablet form and is used to treat schizophrenia, including cases that are resistant to other treatments. It is recognized in medical literature for its efficacy in managing symptoms of psychosis, particularly in patients with a first episode of schizophrenia. Paliperidone acts by blocking dopamine and serotonin receptors, which helps to stabilize mood and reduce hallucinations and delusions. It belongs to the class of atypical antipsychotics, offering a favorable side effect profile compared to traditional antipsychotic medications.

Investigated diseases

  • First Psychotic Episode

    A first psychotic episode refers to the initial occurrence of psychotic symptoms in an individual. These symptoms may include hallucinations, delusions, disorganized thinking, and impaired insight. The onset can be sudden or gradual, and the severity of symptoms can vary. This condition marks the beginning of a potential long-term mental health disorder, often requiring medical evaluation and intervention. Early intervention is crucial to manage symptoms and improve outcomes. The progression can lead to further episodes if not addressed.

  • Schizophrenia

    Schizophrenia is a chronic mental health disorder characterized by disruptions in thought processes, perceptions, emotional responsiveness, and social interactions. Symptoms are typically divided into positive symptoms, such as hallucinations and delusions, and negative symptoms, such as lack of motivation and social withdrawal. The disorder often begins in late adolescence or early adulthood and can vary in severity and duration. Individuals may experience periods of remission and relapse. Schizophrenia affects daily functioning and requires ongoing management. The exact cause is unknown, but it involves a combination of genetic, brain chemistry, and environmental factors.

  • Treatment-resistant Schizophrenia

    Treatment-resistant schizophrenia occurs when a person with schizophrenia does not respond adequately to standard antipsychotic medications. This condition is characterized by persistent symptoms despite treatment efforts. Individuals may continue to experience significant positive and negative symptoms, impacting their quality of life. The progression of this condition can lead to increased disability and challenges in daily functioning. It often requires alternative therapeutic strategies and a comprehensive treatment approach. Understanding the underlying reasons for treatment resistance is crucial for effective management.

Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-516768-28-00Protocol codeSchizOMICSEstimated enrolment244 patientsSponsorConsorcio Centro De Investigacion Biomedica En Red

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