Exploring the serotonin system's role in pain for Parkinson's patients

Pathophysiology of Pain in Parkinson's Disease: Exploration of the Serotonin System in Positron Emission Tomography (PET [18F]-MPPF)

Not applicable Interventional University Hospital, Toulouse · NCT06008704

This study is trying to understand how the serotonin system affects pain in people with Parkinson's Disease to help improve pain management for them.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment34 (estimated)
Ages40 Years to 80 Years
SexAll
SponsorUniversity Hospital, Toulouse Academic / other
Locations1 site (Toulouse, Haute-Garonne)
Trial IDNCT06008704 on ClinicalTrials.gov

What this trial studies

This project investigates how the serotonin system contributes to central pain in patients with Parkinson's Disease (PD). It will involve brain imaging techniques, including positron emission tomography (PET) to visualize serotonin receptors and MRI to assess brain structure and function. The study will compare PD patients experiencing central pain with those who do not, aiming to understand the underlying mechanisms of pain in this population. By examining the nociceptive integration process and the role of serotonin, the research seeks to provide insights into pain management for PD patients.

Who should consider this trial

Good fit: Ideal candidates include Parkinson's patients with chronic central pain or those without pain but meeting specific cognitive and health criteria.

Not a fit: Patients with Parkinson's Disease who do not experience chronic pain or have a VAS score below 4 may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved pain management strategies for patients with Parkinson's Disease.

How similar studies have performed: Previous studies have indicated potential involvement of the serotonergic system in PD-related pain, suggesting this approach may yield valuable insights.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients with PD defined according to United Kingdom Parkinson's Disease Brain Bank (UKPDSBB) criteria
* Patients with stable anti-parkinsonian treatment for at least 4 weeks prior to inclusion
* Patients with a Montreal Cognitive Assessment (MoCA) score \> 25
* Patients with a Hospital Anxiety and Depression Scale (HADS)-D score ≥ 11
* Person affiliated or benefiting from a social security scheme.
* Free, informed and written consent signed by the participant and the investigator (at the latest on the day of inclusion and before any examination required by the research).

  • For patients with pain
* Patients with PD-related central pain defined according to the criteria of Marques et al, 2019
* Patients with chronic central pain (i.e. present for at least 3 months)
* Patients who have average pain over the previous month according to a VAS ≥ 4.

  • For patients without pain
* Patients who do not have pain defined as VAS ≤ 4, meaning that it does not interfere with daily activity.

Exclusion Criteria:

* Patients treated with second line therapy
* Patients with a history of significant psychiatric pathology according to the investigator
* Patients treated with drugs interacting with 5HT1A receptors in the previous 4 weeks
* Patients with contraindication to MRI
* Patients refusing to be informed of an abnormality discovered during brain imaging
* Patients with dyskinesias judged by the investigator to be disabling for imaging.
* Patients under guardianship or other legal protection, deprived of their liberty by judicial or administrative decision
* Pregnant woman, breastfeeding woman

Where this trial is running

Toulouse, Haute-Garonne

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Parkinson DiseasePD-related central painPET [18F] MPPFserotoninergic systemmultimodal imagingpain threshold
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.