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Recruiting Phase 4 NCT04373317

NCT04373317 Pimavanserin vs. Quetiapine for Treatment of Parkinson's Psychosis

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Clinical Trial Summary
NCT ID NCT04373317
Status Recruiting
Phase Phase 4
Sponsor VA Office of Research and Development
Condition Parkinson's Disease Psychosis
Study Type INTERVENTIONAL
Enrollment 358 participants
Start Date 2022-10-24
Primary Completion 2026-10-24

Eligibility & Interventions

Sex All sexes
Min Age 40 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
PimavanserinQuetiapine

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 4 studies follow an already-approved treatment in real-world conditions to monitor long-term safety and effectiveness.

This trial targets 358 participants in total. It began in 2022-10-24 with a primary completion date of 2026-10-24.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

Patients with Parkinson's disease (PD) sometimes experience symptoms affecting their movement, such as slowness, tremor, stiffness, and balance or walking problems. Many patients also have other symptoms not related to movement, called non-motor symptoms, which may affect one's mood or emotions, memory or thinking, or cause one to see or hear things that aren't real (hallucinations) or believe things that aren't true (delusions). Hallucinations or delusions, together called psychosis, occur in up to 60% of PD patients at some point in time. Parkinson's disease psychosis can sometimes be associated with decreased quality of life, increased nursing home placement, increased rate of death, and greater caregiver burden. There are approximately 50,000 Veterans with Parkinson's disease receiving care in the VA, and up to 30,000 (60%) of them will experience psychosis at some point in time. Quetiapine is an antipsychotic drug approved by the Food and Drug Administration (FDA) that is the most commonly used medication to treat PD psychosis, but more studies are needed to determine if it works for this condition and is also well tolerated and safe. Pimavanserin is a newer antipsychotic drug approved by the Food and Drug Administration (FDA) specifically to treat PD psychosis, but more studies are needed to determine if it works and its safety. The purpose of this research is to gather additional information on the safety and effectiveness of both Quetiapine and Pimavanserin. By doing this study, the investigators hope to learn which of these medications is the most effective course of treatment for people with PD psychosis. Enrollment is open to Veterans nationwide, see your VA provider about the possibility of being referred to one of the study's Hub sites. This can be done through contact from your provider to the study's NSC (Tamara Boney at 267-303-9829).

Eligibility Criteria

Inclusion Criteria: * Veteran * Age 40 years or older * Diagnosis of Parkinson's Disease consistent with UK Parkinson's Disease Society Brain Bank Clinical Diagnostic Criteria * Psychosis \[with Neuropsychiatric Inventory (NPI) hallucinations (B) or delusions (A) score 4 or greater\] * Stable dose of PD medications for at least 2 weeks * If on an acetylcholinesterase inhibitor (AChEI) initially prescribed at least 3 months prior and stable dose (no dose or medication change) for past month * Informed other must provide informed consent and agree to attend all study visits. The informed other must be at least 18 years of age and have regular contact with the patient (on average at least 4 days per week and at least 2 hours per day, or at least 3 days per week and at least 4 hours per day, that is with patient) via in-person, video, or telephone * English-speaking INFORMED OTHER * Age 18 years or older * Must have regular contact with the patient (on average at least 4 days per week, and at least 2 hours per day, or at least 3 days per week and at least 4 hours pr day, that is with patient) via in-person, video, or telephone * Agree to attend all study visits * Be able to provide informed consent * English-speaking Exclusion Criteria: * Psychosis symptoms severe enough to preclude enrollment in a clinical trial and require prompt clinical care instead * Treatment with quetiapine \>50 mg/day or pimavanserin in the past 3 months, or quetiapine 50 mg/day or another antipsychotic in the past week prior to study randomization * Deep brain stimulation (DBS) surgery within 3 months or has had stimulator adjustments in the previous 2 weeks * History of a psychotic disorder prior to PD, including bipolar disorder, schizophrenia, schizoaffective disorder, and major depressive disorder with psychotic features, if it is thought to be the cause of the current psychosis symptoms * Suspected atypical parkinsonian disorder or dementia with Lewy bodies (DLB) * Psychosis secondary to other toxic or metabolic disorder * History of long QT syndrome * Documented chart evidence indicating persistent hypoglycemia, hypokalemia, hypomagnesemia that would put patient at increased risk for QTc prolongation. * History of ventricular arrhythmias, except when treated with an implantable cardioverter defibrillator (ICD) or pacemaker, or untreated or unstable atrial fibrillation/flutter * Currently taking medications that are moderate or strong CYP3A4 inducers or strong CYP3A4 inhibitors * Concomitant use of drugs that prolong the QTc interval with a known risk of Torsades de Pointes * Comorbid medical condition determined too severe by Site Investigator to allow participation in clinical trial * Failure to tolerate quetiapine or pimavanserin previously * Severe cognitive impairment (MoCA score \<5) * Nursing home placement at screening or planned placement during the study, unless approved by study Co-Chairs. Approval will depend upon nursing facility agreement to receive, return, and administer medications or allow participant to self-administer study medications; appropriate IO availability; and transportation availability for study visits. * Currently enrolled in another therapeutic or interventional study * Pregnant, or a female of child-bearing potential who is unwilling to use a reliable form of contraception

Contact & Investigator

Central Contact

Daniel Weintraub, MD

✉ daniel.weintraub@va.gov

📞 (215) 823-5800

Principal Investigator

Daniel Weintraub, MD

STUDY CHAIR

Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA

Frequently Asked Questions

Who can join the NCT04373317 clinical trial?

This trial is open to participants of all sexes, aged 40 Years or older, studying Parkinson's Disease Psychosis. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT04373317 trial and what does that mean for participants?

Phase 4 studies are conducted after a treatment has been approved. They monitor long-term safety and real-world effectiveness in a broader patient population.

Is NCT04373317 currently recruiting?

Yes, NCT04373317 is actively recruiting participants. Contact the research team at daniel.weintraub@va.gov for enrollment information.

Where is the NCT04373317 trial being conducted?

This trial is being conducted at Tucson, United States, Loma Linda, United States, Palo Alto, United States, San Francisco, United States and 11 additional locations.

Who is sponsoring the NCT04373317 clinical trial?

NCT04373317 is sponsored by VA Office of Research and Development. The principal investigator is Daniel Weintraub, MD at Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA. The trial plans to enroll 358 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: July 2026  ·  Data Methodology