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Study of ACP-204 for Treating Psychosis in Adults with Alzheimer's Disease

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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 a condition known as Alzheimer's Disease Psychosis, which affects some individuals with Alzheimer's disease, causing symptoms like hallucinations and delusions. The trial will test a new treatment called ACP-204, which is taken as a capsule. The purpose of the study is to evaluate how effective and safe ACP-204 is for treating these symptoms in adults.

Participants in the study will receive either ACP-204 or a placebo, which looks like the treatment but does not contain the active substance. The study will compare the effects of two different doses of ACP-204, 30 mg and 60 mg, to see how well they work in reducing symptoms. The treatment period will last up to six months, during which participants will take the medication orally, meaning by mouth.

The study aims to gather information on how ACP-204 affects the symptoms of Alzheimer's Disease Psychosis over time. Participants will be monitored regularly to assess changes in their condition and to ensure their safety throughout the study. This research is important for understanding potential new treatments for managing symptoms associated with Alzheimer's disease.

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, eligibility is confirmed based on specific criteria such as age, living situation, and medical history related to Alzheimer's disease and psychosis.

    A study partner or caregiver is required to assist with study visits and ensure adherence to the study protocol.

  2. Step 2

    Initial assessment

    An initial assessment is conducted to establish a baseline for the study. This includes evaluating psychotic symptoms and cognitive function using standardized scales.

    A blood-based biomarker or other documented evidence is reviewed to confirm amyloid plaque deposition consistent with Alzheimer's disease.

  3. Step 3

    Medication administration

    Participants receive either ACP-204 or a placebo in capsule form, taken orally.

    The dosage of ACP-204 is either 30 mg or 60 mg, administered as per the study protocol.

  4. Step 4

    Ongoing assessments

    Regular assessments are conducted to monitor the efficacy and safety of the treatment. This includes evaluating changes in psychotic symptoms from baseline to Week 6 using the Scale for the Assessment of Positive Symptoms-Hallucinations and Delusions subscales.

    Secondary assessments may include other scales to measure overall improvement.

  5. Step 5

    Completion of study

    The study is expected to continue until 2028, with participants completing all required visits and assessments as per the study schedule.

    Final evaluations are conducted to assess the overall impact of the treatment on Alzheimer's disease psychosis.

Who can join the trial?

11 criteria

  • The patient must be a male or female aged between 55 and 85 years old, living either in the community or in a care facility.
  • The patient should be able to attend all study visits with a study partner or caregiver.
  • If the patient is taking a medication called a cholinesterase inhibitor or memantine, the dose must be stable. These medications are often used to help with memory and thinking problems.
  • The patient must meet the clinical criteria for possible or probable Alzheimer's Disease (AD) based on guidelines from the National Institute on Aging-Alzheimer Association (NIA-AA).
  • The patient must meet the revised criteria for psychosis in major or mild neurocognitive disorder as established by the International Psychogeriatrics Association (IPA). Psychosis refers to symptoms like seeing or hearing things that are not there.
  • The patient must have either a blood test or other evidence, like a brain scan or spinal fluid test, showing amyloid plaque buildup and changes in the brain that are consistent with Alzheimer's Disease.
  • The patient must have had a previous brain scan, such as a magnetic resonance imaging (MRI) or computed tomography (CT) scan, that supports the diagnosis of Alzheimer's Disease.
  • The patient must have a score between 6 and 24 on the Mini-Mental State Examination (MMSE), a test that measures thinking and memory skills.
  • The patient must have experienced psychotic symptoms for at least 2 months.
  • The patient must live in a stable place of residence with no plans to change living arrangements.
  • The patient must have a designated study partner or caregiver.

Who cannot join the trial?

5 criteria

  • Patients who do not have Alzheimer Disease psychosis cannot participate. This means the study is only for those who have this specific condition.
  • Patients who are not within the specified age range cannot participate. The study is for certain age groups only.
  • Patients who are not part of the specified clinical trial groups cannot participate. This means the study is for specific groups of people.
  • Both male and female patients can participate, but those who do not meet other criteria cannot join.
  • Patients who are not considered part of a vulnerable population cannot participate. A vulnerable population includes people who might need special protection or care.
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Investigated drugs

ACP-204 is a medication being studied for its potential to help adults with Alzheimer's Disease who experience psychosis. The trial aims to understand how effective ACP-204 is in treating symptoms of psychosis in these patients. The study will also look at how the body responds to the medication to determine the best dose for treatment.

What is already known about the treatment

ACP-204 – ACP-204 is administered orally in tablet form and is currently being studied in clinical trials for its effectiveness in treating psychosis associated with Alzheimer's disease. It is in the Phase 2 stage of clinical trials, where its efficacy and dose response are being evaluated. The main therapeutic indication for ACP-204 is to manage symptoms of psychosis in individuals with Alzheimer's disease. At the molecular level, ACP-204 is believed to work by modulating neurotransmitter systems in the brain, which may help reduce psychotic symptoms. It is classified pharmacologically as an antipsychotic medication.

Investigated diseases

Alzheimer Disease Psychosis – This condition is a manifestation of Alzheimer's disease characterized by symptoms such as hallucinations and delusions. It typically occurs in the later stages of Alzheimer's, affecting the patient's perception of reality. Hallucinations may involve seeing or hearing things that are not present, while delusions are false beliefs that are resistant to reason or contrary evidence. These symptoms can lead to increased distress and confusion for the individual. The progression of psychosis in Alzheimer's can vary, with symptoms sometimes fluctuating in intensity. Understanding and managing these symptoms is crucial for improving the quality of life for those affected.
Trial detailsLast updated 4 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-507325-42-00Estimated enrolment1 074 patientsSponsorAcadia Pharmaceuticals Inc.

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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).