RecruitingPhase 2 / PHASE3

ACP-204 in Adults With Alzheimer's Disease Psychosis

A Master Protocol for Three Independent, Seamlessly Enrolling, Double-blind, Placebo-controlled Efficacy and Safety Studies of ACP-204 in Adults With Alzheimer's Disease Psychosis

Lead sponsor

ACADIA Pharmaceuticals Inc.

Asset

ACP-204

Listed sites

145

Recruiting sites

Enrollment

1,074

estimated

Study population

Alzheimer’s disease

Key I/E criteria

•Alzheimer's disease•MMSE 6-24•Study partner/caregiver required•AD symptomatic therapy: stable

Primary endpoint

•Scale for the Assessment of Positive Symptoms-Hallucinations

Footprint

Where this trial recruits

Site locations as reported to ClinicalTrials.gov. Site count is not enrollment count; per-site enrollment is not available from source.

Identifiers

Registered as

Org study IDACP-204-006

NCT IDNCT06159673

Timeline

Milestones

Study start2023-11-14actual

Study first posted2023-12-07actual

Last update posted2026-06-16actual

Primary completion2028-01estimated (month precision)

Study completion2028-02estimated (month precision)

Assets

Drug assets

ACP-204

Study populations

Who this study enrolls

Alzheimer’s disease

Eligibility

Who can enroll

Minimum age55 Years

Maximum age95 Years

SexAll

Healthy volunteersNot accepted

Inclusion criteria

•Is male or female and ≥55 and ≤95 years of age living in the community or in an institutionalized setting

•Meets clinical criteria for possible or probable AD based on the 2011 National Institute on Aging-Alzheimer Association (NIA-AA) criteria

•Meets the revised criteria for psychosis in major or mild neurocognitive disorder established by the International Psychogeriatrics Association (IPA)

•Has either blood-based biomarker or documented evidence (e.g. positron emission tomography, cerebrospinal fluid biomarker) indicating amyloid plaque deposition and neuropathologic change consistent with AD

•Has a prior magnetic resonance imaging or computed tomography scan of the brain that is consistent with the diagnosis of AD

•Meets revised criteria for psychosis in major or mild neurocognitive disorder as per International Psychogeriatrics Association

•MMSE score ≥6 and ≤24

•Psychotic symptoms for at least 2 months

•Lives in a stable place of residence and there are no plans to change living arrangements

•Has a designated study partner/caregiver

•Able to complete all study visits with a study partner/caregiver

•Must be on a stable dose of cholinesterase inhibitor or memantine, if applicable

Exclusion criteria

•Requires treatment with a medication prohibited by the protocol

•Is in hospice and receiving end-of-life palliative care, or has become bedridden

•Requires skilled nursing care

•Psychotic symptoms that are primarily attributable to delirium, substance abuse, or a medical or psychiatric condition other than dementia

•Known history of cerebral amyloid angiopathy, epilepsy, central nervous system neoplasm, or unexplained syncope

•Atrial fibrillation

•Symptomatic orthostatic hypotension

•Protocol-defined exclusionary clinical laboratory findings

•Treatment with anti-tau therapy or donanemab within 2 months prior to Screening

Additional inclusion/exclusion criteria apply. Subjects will be evaluated at screening to ensure that all criteria for study participation are met.

Endpoints (2)

What's being measured

Protocol endpoints and posted registry outcome measures, grouped into outcome categories. Composite endpoints show their component event types. Standard codes (LOINC, SNOMED CT) are shown where available.

Coverage by outcome category

Other clinical outcomes

Other (unclassified)

Other clinical outcomes

1 endpoint

Secondary/protocol endpoint

Clinical Global Impression-Severity in the ADP context (CGI-S-ADP) score

Time frame:Baseline to Week 6

descriptive

Other (unclassified)

1 endpoint

Primary/protocol endpoint/low confidence

Scale for the Assessment of Positive Symptoms-Hallucinations and Delusions subscales (SAPS-H+D) total score change from baseline (Substudies 1, 2A, 2B)

Time frame:From baseline to Week 6

change from baseline, improvement

Provenance

Sources

Trial identity, design, statusClinicalTrials.gov API v2

Snapshot dateJuly 21, 2026

Endpoint classificationDelfa ADRD endpoint taxonomy

Results tableno registry results posted yet

Trial facts come from public ClinicalTrials.gov records. Endpoint categories are Delfa's classification of those records, not a ClinicalTrials.gov field. All figures reflect the July 21, 2026 snapshot.