Evaluation of Adhesion Properties of Rotigotine Transdermal Patch in Parkinson's Disease: A Randomized, Open-Label, Crossover Study

The primary objective of this clinical trial is to assess the **skin adhesion** properties of a newly developed Rotigotine 12 mg/24 h transdermal patch, specifically at the end of the dosing interval. This involves a comparative evaluation of the adhesion properties between the Test and Reference products. The clinical relevance of this objective lies in ensuring the effective delivery of the active substance, **Rotigotine**, which is crucial for managing symptoms in patients with Parkinson's disease. Proper adhesion is essential to maintain consistent drug delivery and therapeutic efficacy.

Secondary objectives include:

• Evaluating the skin tolerability of both the Test and Reference products through a standardized assessment of Adverse Events of Special Interest.
• Providing a descriptive characterization of the safety and tolerability of the investigational medicinal products in the trial population.

The clinical trial involves participants diagnosed with **Parkinson's disease**, specifically idiopathic Parkinson's disease. The study population includes both male and female subjects aged 18 years or older. Participants are required to be of Caucasian ethnicity and must have been on a stable dose of at least 12 mg/24 h rotigotine for a minimum of two weeks prior to enrollment. The trial population was selected based on these criteria, and participants must agree to refrain from swimming, bathing, or using a sauna on assessment days. The sponsor has not provided information regarding the total number of participants. The study includes a vulnerable population, and all participants have provided written informed consent after being informed about the potential risks and benefits of the trial.

The clinical trial is designed as a **randomized**, open-label, crossover study to evaluate the adhesiveness of a newly developed **rotigotine** 12 mg/24 h transdermal patch in patients diagnosed with **Parkinson's disease**. The trial aims to assess the skin adhesion properties of the test product compared to a reference product at the end of the dosing interval. The study is expected to commence on October 15, 2025, with an estimated completion date of December 15, 2025, indicating a total trial duration of approximately two months.

Participants will be required to attend several study visits, beginning with an inclusion (screening) visit to confirm eligibility based on criteria such as age, diagnosis, and current medication regimen. The principal inclusion criteria include being of Caucasian ethnicity, aged 18 years or older, having a diagnosis of idiopathic Parkinson's disease, and being on a stable dose of at least 12 mg/24 h **rotigotine** for a minimum of two weeks prior to enrollment. Participants must also agree to refrain from swimming, bathing, or using a sauna on assessment days. Written informed consent is mandatory.

Following the screening, participants will undergo a series of follow-up visits to monitor the primary endpoints, which include the mean adhesion of the test patch at 23 hours and 55 minutes, and the difference in adhesiveness between the test and reference products at the same time point. Secondary endpoints will focus on the frequency of adverse events of special interest (AESIs) and other adverse events (AEs). The end-of-study visit will conclude the trial, where final assessments and data collection will occur.

The expected length of participant involvement is approximately two months, aligning with the trial's overall duration. Conditions that may lead to early termination from the study include non-compliance with the study protocol, withdrawal of consent, or the occurrence of significant adverse events. The trial is categorized as a Phase 4 study, focusing on the practical application of the patch in a real-world setting, and is not considered a low-intervention trial.

The clinical trial involves the use of **rotigotine** in the form of a transdermal patch, specifically the Neupro 8 mg/24 h transdermal patch. This patch is manufactured by UCB PHARMA S.A. and is designed for **transdermal use**. The patch delivers a maximum daily dose of 8 mg of rotigotine, with a total maximum dose of 16 mg over a treatment period of up to 2 days. The patch is applied once every 24 hours, ensuring continuous delivery of the active substance. The primary and secondary labeling and packaging of the product have been modified for the trial. The Neupro patch is classified as a dopamine agonist and is not a pediatric formulation.

Another product used in the trial is the ROT-TDS transdermal patch, which also contains **rotigotine** as the active substance. This patch is produced by LUYE PHARMA SWITZERLAND AG and is similarly intended for **transdermal use**. The ROT-TDS patch provides a higher maximum daily dose of 12 mg, with a total maximum dose of 24 mg over a 2-day treatment period. Like the Neupro patch, the ROT-TDS is applied once every 24 hours. It is also categorized as a dopamine agonist and is not formulated for pediatric use. The trial aims to assess the skin adhesion properties of this newly developed patch in patients with Parkinson's disease.

The efficacy of the clinical trial will be assessed through the evaluation of the skin adhesion properties of a newly developed **rotigotine** 12 mg/24 h transdermal patch in patients with Parkinson's disease. The primary endpoints for efficacy include the mean adhesion of the test product at 23 hours and 55 minutes, as well as the difference in adhesiveness between the test and reference products at the same time point. These measurements will provide a comparative assessment of the skin adhesion properties of the test and reference products.

Secondary endpoints will focus on the safety profile, including the frequency of adverse events of special interest (AESIs) and the overall frequency of adverse events (AEs). The trial is designed as a comparative, randomized, open, crossover study, ensuring a robust evaluation of the patch's adhesiveness. The trial is set to begin recruitment on October 15, 2025, with an estimated end date of December 15, 2025. The study will involve the administration of a stable dose of at least 12 mg/24 h **rotigotine** for at least two weeks prior to enrollment, ensuring consistency in the evaluation of the patch's adhesion properties.