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Long-Term Safety Study of ACP-204 for Adults with Alzheimer's Disease Psychosis

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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 long-term effects of a medication called ACP-204 in adults who have a condition known as Alzheimer's Disease Psychosis. Alzheimer's Disease Psychosis is a condition where individuals with Alzheimer's disease experience symptoms such as hallucinations or delusions. The medication being tested, ACP-204, is taken in the form of a capsule and is designed to help manage these symptoms.

The purpose of this study is to evaluate how safe and tolerable ACP-204 is when used over a long period, specifically 52 weeks. Participants in the study will take the medication orally, meaning they will swallow the capsule. The study will monitor participants for any side effects or adverse reactions to the medication during this time. This is an extension study, meaning it follows up on a previous study to gather more information about the medication's long-term use.

Throughout the study, participants will be regularly assessed to ensure their well-being and to track any changes in their condition. The study aims to provide valuable information on the safety of ACP-204 for individuals with Alzheimer's Disease Psychosis, contributing to a better understanding of how this medication can be used in managing the condition over an extended period.

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

    Joining the study

    Participation begins after successful completion of the ACP-204-006 study.

    Eligibility requires being between 55 and 85 years old, with specific conditions for females and males regarding childbearing potential.

    A study partner or caregiver must be designated to assist throughout the study.

    A signed informed consent form is required, involving a caregiver or legal representative.

  2. Step 2

    Medication administration

    The medication used is acp-204 tartrate, administered in capsule form.

    The route of administration is oral use.

    The study aims to evaluate the long-term safety and tolerability of this medication in individuals with Alzheimer's Disease Psychosis (ADP).

  3. Step 3

    Treatment duration

    The study is conducted over a period of 52 weeks.

    Participants will receive the medication throughout this duration.

  4. Step 4

    Monitoring and evaluation

    The primary focus is on identifying any treatment-emergent adverse events over the 52 weeks.

    The study will monitor the number of subjects experiencing adverse events, discontinuations due to adverse events, and serious adverse events.

    A secondary evaluation involves the Clinical Global Impression-Improvement in the ADP context (CGI-I-ADP) score.

Who can join the trial?

5 criteria

  • The patient must have successfully completed the ACP-204-006 study.
  • The patient can be male or female, aged between 55 and 85 years old. If female, she must not be able to have children. If male, he must use a suitable method to prevent pregnancy if his partner can have children.
  • The patient must have a designated study partner or caregiver. This is someone who helps and supports the patient during the study.
  • The patient and their study partner or caregiver must be able to attend all study visits together.
  • The patient must have signed a consent form, which is an agreement to participate in the study, with the help of a caregiver or legal representative.

Who cannot join the trial?

7 criteria

  • Patients who do not have a diagnosis of Alzheimer's 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 adults, so children and very elderly individuals may not be eligible.
  • Patients who are not able to follow the study procedures or take the study medication as required cannot participate. This means if someone cannot understand or follow the instructions, they may not be eligible.
  • Patients who have other serious health conditions that might interfere with the study cannot participate. This means if someone has another illness that could affect the study results, they may not be eligible.
  • Patients who are pregnant or breastfeeding cannot participate. This is to ensure the safety of both the mother and the baby.
  • Patients who are currently participating in another clinical trial cannot participate. This is to avoid any interference between different study treatments.
  • Patients who have a history of allergic reactions to the study medication cannot participate. This is to prevent any potential allergic reactions during the study.
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Investigated drugs

ACP-204 is a medication being studied for its effects on adults with Alzheimer's Disease Psychosis. The trial aims to evaluate the safety and tolerability of using this medication over a long period. Participants in the study will receive ACP-204 to see how well they can tolerate it and to monitor any side effects that may occur during the treatment.

What is already known about the treatment

ACP-204 – ACP-204 is administered orally in the form of tablets. It is currently under investigation in clinical trials, specifically in a 52-week open-label extension study, to assess its safety and tolerability for long-term use in adults with Alzheimer's Disease Psychosis. The main therapeutic indication for ACP-204 is to manage symptoms associated with psychosis in Alzheimer's patients. At the molecular level, ACP-204 is believed to work by modulating neurotransmitter systems in the brain, which may help alleviate psychotic symptoms. It is classified pharmacologically as an antipsychotic medication.

Investigated diseases

Alzheimer's Disease Psychosis – Alzheimer's Disease Psychosis is a condition that occurs in some individuals with Alzheimer's disease, characterized by symptoms such as hallucinations and delusions. These symptoms can significantly affect the behavior and emotions of the person experiencing them. The progression of Alzheimer's Disease Psychosis can vary, with symptoms potentially becoming more frequent or severe over time. It is often associated with the later stages of Alzheimer's disease, although it can occur at any stage. The presence of psychosis can complicate the care and management of individuals with Alzheimer's, impacting their quality of life and interactions with caregivers.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-507351-29-00Protocol codeACP-204-008Estimated enrolment752 patientsSponsorAcadia Pharmaceuticals Inc.

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