Comparing two medications for treating psychosis in Parkinson's disease and dementia with Lewy bodies
Official title: A Pragmatic Randomized Trial Comparing Antipsychotics in Lewy Body Disease
Run by The University of Texas Health Science Center at San Antonio · NCT05590637 · Data updated 2026-11-12
This study is testing which of two medications, pimavanserin or quetiapine, works better to help people with psychosis caused by Parkinson's disease or dementia with Lewy bodies.
Quick facts
| Phase | Phase 4 |
|---|---|
| Study type | Interventional |
| Sex | All |
| Enrollment | 94 (estimated) |
| Sponsor | The University of Texas Health Science Center at San Antonio Academic / other |
| Locations | 2 sites (San Antonio, Texas and 1 other locations) |
| Status | Recruiting |
| Started | April 22, 2022 |
| Main results expected | August 2026 |
| Study ends | February 2027 |
| Registry record updated | September 9, 2025 |
| Trial ID | NCT05590637 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates for this study are patients diagnosed with psychosis due to Parkinson's disease or dementia with Lewy bodies who require initiation of an antipsychotic medication.
✕Probably not a fit
Patients who are currently taking an antipsychotic medication or have medical contraindications to either pimavanserin or quetiapine may not benefit from this study.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This clinical trial aims to compare the effectiveness of two antipsychotic medications, pimavanserin and quetiapine, in treating psychosis associated with Parkinson's disease and dementia with Lewy bodies. Patients diagnosed with psychosis due to these conditions will be randomly assigned to receive either medication, and their improvement in symptoms will be assessed over a six-month period. The study seeks to provide clarity on which medication may offer better outcomes in a routine clinical setting. By focusing on real-world treatment scenarios, the trial aims to enhance understanding of psychosis management in Lewy body disease.
Why it matters
Potential benefit: If successful, this study could lead to more effective treatment options for patients experiencing psychosis due to Parkinson's disease or dementia with Lewy bodies.
How similar studies have gone: While there have been few comparison studies between these two medications, this trial aims to fill a gap in the existing literature, making it a novel approach.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * Patients seen in the neurology clinic at UT Health San Antonio * Diagnosed with psychosis due to PD or DLB * Requiring initiation of an antipsychotic medication * Clinical equipoise between quetiapine and pimavanserin must exist * The prescribing provider must be comfortable prescribing and managing both quetiapine and pimavanserin Exclusion Criteria: * Medical contraindication to either medication * Caregiver unavailable to complete NPI-Q * Currently taking an antipsychotic medication * Prescribing provider unwilling to manage either medication
Where it's running
-
University Health System
San Antonio, Texas, United States Recruiting -
UT Health Science Center - San Antonio
San Antonio, Texas, United States Recruiting
Study contacts
- Principal investigator: Sarah Horn, MD — The University of Texas Health Science Center at San Antonio
- Study coordinator: Carolyn Paiz, BS
- Email: paizc@uthscsa.edu
- Phone: 210-450-8830
Similar studies
Other studies for the same condition or treatment. Recruiting studies are listed first.
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Predicting disease progression in dementia using biomarkers and modeling
This study is trying to create a tool that helps predict how dementia will progress in people with mild cognitive impairment and different types of dementia, like Alzheimer's and Lewy Body Disease, by looking at brain scans, body fluids, and mental tests.
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This study is testing two different imaging techniques to see which one better helps doctors tell apart Parkinson's disease, multiple system atrophy, dementia with Lewy bodies, and Alzheimer's disease in patients and healthy volunteers.
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.