A study to evaluate whether prasinezumab can slow down certain signs of Parkinson’s disease (PD) progression compared to placebo, and how safe prasinezumab is, in people already treated for symptoms of Parkinson’s disease.

How does the PADOVA trial work? 

The purpose of this clinical trial is to compare the effects, good or bad, of prasinezumab against placebo in patients with PD when taken with other medications to treat symptoms of PD. A ‘placebo’ medicine looks the same as the medicine in the trial (active medicine) but does not contain any active medicine. In this clinical trial, participants will get either prasinezumab or placebo on top of usual PD medication to treat symptoms.

How do I take part in this clinical trial? 

To be able to take part in this clinical trial, you must have a diagnosis of PD for at least 6 months to a maximum of 3 years, be treated with PD medication to treat symptoms for at least 6 months (with stable doses for 3 months prior to the first administration of prasinezumab), and be aged 50-85 years old. 

It is also expected that your PD medication to treat symptoms remains unchanged (dose and type of medication) throughout the study duration and that you are willing to use a smartphone application to measure your PD-related symptoms on a daily basis for the duration of the study. 

You must not have been diagnosed with another central nervous system disease other than PD (e.g. dementia, stroke, epilepsy ….). You cannot participate in this study if you have uncontrolled hypertension or if within the last year you suffered from a significant cardiovascular disease.

While taking part in the clinical trial, women (not currently pregnant but who can become pregnant) will need to either not have heterosexual intercourse or take contraceptive medication for safety reasons.

If you think this clinical trial may be suitable for you and would like to take part, please talk to your doctor. If your doctor thinks that you might be able to take part in this clinical trial, he/she may refer you to the closest clinical trial doctor. They will give you all the information you need to make your decision about taking part in the clinical trial. You can also find the clinical trial locations on this page.

You will have some tests to make sure you will be able to take the treatments given in this clinical trial. This process is called “screening”. Some of these tests or procedures may be part of your regular medical care. They may be done even if you do not take part in the clinical trial. Before starting the clinical trial, you will be told about any risks and benefits of taking part in this trial. You will also receive information regarding the test and procedures included in this trial and the duration of the trial.

What treatment will I be given if I join this clinical trial?  

Everyone who joins this clinical trial will be assigned to one of 2 groups randomly (like flipping a coin) and given either: 

• prasinezumab, given as an infusion (into the vein) every 4 weeks for at least 18 months (1.5 years), in addition to your usual PD medication to treat your symptoms
• OR placebo, given as an infusion (into the vein) every 4 weeks for at least 18 months (1.5 years), in addition to your usual PD medication to treat your symptoms.

This is a ‘placebo-controlled’ clinical trial, which means that one of the groups will be given medicine with no active medicine (‘placebo’). You will have an equal chance of being placed in any group. 

As this is also a “double-blind” clinical trial, neither you nor your clinical trial doctor can choose or know the group you are in. However, your clinical trial doctor can find out which group you are in for health and safety reasons. 

How often will I be seen in follow-up appointments, and for how long?

You will be required to attend visits every 4 weeks during the treatment period. You will receive the clinical trial treatment prasinezumab OR placebo for at least 18 months (1.5 years). The treatment period will continue at least until the last participant included in the study has been treated for a minimum of 18 months (1.5 years). This is necessary to collect enough data to answer the question this study is designed to ask. Because of this, the length of your treatment period will depend on whether you were one of the first or last participants to join the trial. As a result, it is not possible to determine ahead of time exactly how long you will be receiving study treatment. Your time receiving treatment could range from approximately 18 months (1.5 years) to more than 30 months (2.5 years). 

You are free to stop being in this clinical trial at any time. After being given your very last dose, you will still be seen by the clinical trial doctor 2 times for your safety. These visits will include tests and procedures to see how you are responding to the treatment and any side effects that you may be having. 

What happens if I am unable to take part in this clinical trial?

If this clinical trial is not suitable for you, you will not be able to take part. Your doctor will suggest other clinical trials that you may be able to take part in or other treatments that you can be given. You will not lose access to any of your regular care.

For more information about this clinical trial see the For Expert tab on the specific ForPatient page or follow this link to ClinicalTrials.gov https://www.clinicaltrials.gov/ct2/show/NCT04777331

Trial-identifier: NCT04777331