A Phase 2 interventional study of ACP-204 and Placebo in Lewy Body Dementia Psychosis, sponsored by ACADIA Pharmaceuticals Inc.. Recruiting at 62 sites in 6 countries. Open to participants aged 55 Years to 84 Years. Per ClinicalTrials.gov, last updated 2026-11-04.
Sponsored by ACADIA Pharmaceuticals Inc. · Phase 2, Interventional, and Treatment
Multicenter, randomized, 6-week, double-blind, placebo-controlled, parallel-group, Phase 2 study in subjects with LBDP.
Study Website: https://illumerastudy.com/
239 studies on the registry are indexed under Lewy Body Disease; 89 are open to participants now.
This study's planned enrollment of 180 is above the median of 89 across 152 interventional studies indexed under Lewy Body Disease.
Browse Lewy Body Disease studies →ACADIA Pharmaceuticals Inc. is the lead sponsor of 41 studies on the registry; 5 are open to participants now.
Of its 26 completed or terminated interventional studies of FDA-regulated products, 24 (92%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Can provide written . If the subject is deemed not competent to provide informed consent, the following requirements for consent must be met:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ACP-204 dose of 30 mg once daily
Drug: ACP-204
ACP-204 dose of 60 mg once daily
Drug: ACP-204
Placebo once daily
Drug: Placebo
Provided as 1 capsule, to be taken orally once daily
Provided as 1 capsule, to be taken orally once daily
Change from Baseline in SAPS-LBDP total score at Week 6
Change from Baseline in Scale for the Assessment of Positive Symptoms- Lewy Body Dementia Psychosis (SAPS-LBDP) total score at Week 6
Time frame: 6 weeks
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Plan to share: No
No publications or documents are linked to this record.
Started Aug 2025 (actual). Primary completion is estimated for Feb 2028, 30 months after the start.
Of 24 phase 2 interventional studies under Lewy Body Disease, half reached primary completion within 26 months of starting (the median), counting those still running; a quarter within 16 and three quarters within 45. This study's planned 30 months is above that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drug tested here: Remlifanserin