An observational study in Parkinson's Disease, sponsored by Bayer. Recruiting at 27 sites in United States. Open to participants aged 45 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-09-04.
Sponsored by Bayer · Observational
This is an observational study in which data are collected and studied from Parkinson's disease patients who have movement symptoms despite taking standard Parkinson's medications. In observational studies, observations are made without any changes to the participant's healthcare or treatment plan. No investigational product will be administered in this study, as participants will be treated with the standard of care that medical experts currently consider most appropriate.
Parkinson's disease (PD) is a condition that affects the brain and causes problems with movement and other body functions. The symptoms of Parkinson's disease can worsen over time. People with Parkinson's disease may experience shaking (tremor), slow movements, stiff muscles, trouble walking, and problems with balance. They can also have other symptoms, such as difficulty thinking clearly, changes in mood, or difficulty sleeping. Parkinson's disease mostly affects older adults, but it can happen to younger people too. There is no cure, but treatments can help manage the symptoms and improve quality of life.
While doctors and researchers know that Parkinson's disease affects people in different ways and can worsen over time, there are still many things they don't fully understand-especially for people who experience movement symptoms despite taking their usual Parkinson's medicines. Earlier studies did not follow these patients long enough or collect all the important information needed. This study is being done to fill those gaps.
The main purpose of this study is to better understand how Parkinson's disease changes over time in patients who experience movement symptoms while taking standard oral Parkinson's medications, what challenges patients and their care partners face, and how their treatments are working in real life. To do this, researchers will collect data on:
Data will come from questionnaires or rating scales conducted by the doctor with the patient during study visits, diaries and logs completed by the patient, medical records, health insurance claims records, blood samples and skin biopsies, a digital device that records movement/non-movement symptoms, and questionnaires completed by the care partner.
Data will be collected from December 2025 to December 2032. Each participant may be followed for up to 5 years.
4,487 studies on the registry are indexed under Parkinson Disease; 1,082 are open to participants now.
This study's planned enrollment of 300 is above the median of 96 across 1,057 observational studies indexed under Parkinson Disease.
Browse Parkinson Disease studies →Bayer is the lead sponsor of 1,643 studies on the registry; 57 are open to participants now.
Of its 209 completed or terminated interventional studies of FDA-regulated products, 129 (62%) have results posted.
Counted across the registry records on this site, refreshed daily.
Patients with Parkinson's disease experiencing motor complications while on antiparkinsonian medications
Inclusion Criteria for Patient:
Exclusion Criteria for Patient:
Inclusion Criteria for Care Partner:
Exclusion Criteria for Care Partner:
A single cohort of patients with Parkinson's disease experiencing motor complications while receiving standard-of-care oral therapies. The care partner of the patient may also participate in the study.
Other: Standard of Care
The care partner of the patient may also participate in the study.
Follow clinical practice/administration. No investigational products will be administered in this study. Patients will be treated in accordance with standard of care as determined by their clinician.
Descriptive summary of motor outcomes among Parkinson's disease patients treated with oral antiparkinsonian medications who experience motor complications.
This outcome will be assessed using Parkinson's disease (PD) Motor (Hauser) Diary, Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Parts II-IV (each part has several items scored from 0-normal to 4-severe; with higher scores indicating greater impairment), modified Hoehn \& Yahr (stages Parkinson's disease severity from 1 \[unilateral involvement only\] to 5 \[wheelchair-bound or bedridden unless aided\]), Universal Dyskinesia Rating Scale (UDysRS) (items scored from 0-none to 4-severe; higher scores indicate more severe dyskinesia), medical records, and digital health technology.
Time frame: From baseline up to 5 years
Descriptive summary of non-motor outcomes among Parkinson's disease patients treated with oral antiparkinsonian medications who experience motor complications.
This outcome will be assessed using Montreal Cognitive Assessment (MoCA, score 0-30, higher = better cognition), MDS-UPDRS I (4-point scale, higher = greater impairment), modified Schwab \& England Activities of Daily Living (0-100%, higher = greater independence), MDS Non-Motor Rating Scale (MDS-NMS, 4-point scale, higher = more severe non-motor symptoms), Parkinson's Disease Questionnaire-39 (PDQ-39, 0-100 scale, higher = worse quality of life), Parkinson's Disease Health Index (PD-HI, higher = worse health status), Parkinson's Disease Sleep Scale 2 (PDSS-2, 4-point scale, higher = more severe sleep problems), Clinical Global Impressions Severity (CGI-S, 7-point scale, higher = greater severity of illness), Patient Global Impression Severity (PGI-S, 7-point scale, higher = greater severity), EuroQoL 5-Dimension 5-Level (EQ-5D-5L, 5 dimensions, 5 levels, plus visual analogue scale (VAS) 0-100 \[100=best imaginable health\]), medical records, and digital health technology.
Time frame: From baseline up to 5 years
Descriptive summary of Parkinson's medications and treatments received
This outcome will be assessed by the logs (Parkinson's medications, Parkinson's advanced therapies, rehabilitation therapies \& mobility assistance devices) completed by the patient, medical records, and health insurance claims records.
Time frame: From baseline up to 5 years
Descriptive summary on the burden of care - psychological dimension
This outcome will be assessed using the Zarit Burden Interview (ZBI), a 22-item questionnaire scored 0-88 (higher scores indicate greater burden).
Time frame: From baseline up to 5 years
Descriptive summary on the burden of care - economic dimension
This outcome will be assessed using the Caregiver Indirect and Informal Care Cost Assessment Questionnaire (CIIQ), which includes 13 questions on work status, productivity, and informal care costs.
Time frame: From baseline up to 5 years
Plan to share: No — Currently, there is no established plan for the sharing of Individual Patient Data (IPD) from this study. The availability of this study's data will later be determined according to Bayer's commitment to the EFPIA/PhRMA 'Principles for responsible clinical trial data sharing.' This pertains to the scope, timepoint, and process of data access. As such, Bayer commits to considering requests from qualified researchers for patient- / study-level clinical trial data, and documents from clinical trials involving medicines and indications approved in the US and EU. However, this commitment does not reflect an active IPD sharing plan. This applies to data on new medicines and indications that have been approved by the EU and US regulatory agencies on or after January 01, 2014. Researchers can use www.vivli.org to request access to IPD and documents from clinical studies to conduct research. Information on Bayer's criteria for listing studies is provided in the member section of the portal.
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