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Contact the study team using the details below to take part. If there are no contact details below please ask your doctor in the first instance.
Dr
Katie
McGoohan
+44 (0)2078486997
canpdp.trialoffice@kcl.ac.uk
Prof
Sagnik
Bhattacharyya
+44 (0)7936545178
canpdp.trialoffice@kcl.ac.uk
Parkinson’s disease psychosis
This information is provided directly by researchers, and we recognise that it isn't always easy to understand. We are working with researchers to improve the accessibility of this information. In some summaries, you may come across links to external websites. These websites will have more information to help you better understand the study.
People with Parkinson’s disease often suffer from unusual experiences such as hallucinations (e.g. seeing things or hearing voices that are not there) or develop delusions (i.e. false beliefs, for example, that someone may be trying to harm them) as part of their illness. These experiences are also known as psychotic symptoms and are distressing both to patients and those caring for them.
More than half of all patients with Parkinson's eventually develop these symptoms over the course of their disorder. These problems can be difficult to manage and can impact quality of life. Currently, existing medications to treat these symptoms are either not very effective or have significant side effects.
The aim of this study is to test a new treatment called cannabidiol (CBD). CBD is a non-addictive substance present in the extract from the cannabis plant that is not responsible for the effects typically produced by cannabis, such as ‘feeling high’. Previous studies not only suggest that CBD may be useful in treating symptoms of psychosis, they also suggest that it is safe to use in older adults.
Although CBD may be a promising treatment for symptoms of psychosis, it is not known whether this treatment will be tolerated well in patients with Parkinson’s-related psychosis, whether it will provide relief from psychotic symptoms, and what doses may work best for people with Parkinson’s-related psychosis. The aim of this study is to address all of these questions.
Start dates may differ between countries and research sites. The research team are responsible for keeping the information up-to-date.
The recruitment start and end dates are as follows:
You can take part if:
You may not be able to take part if:
1. Insufficient understanding of trial2. History of significant psychotic disorders prior to or concomitantly with the diagnosis of Parkinson’s disease including, but not limited to, schizophrenia or bipolar disorder3. Psychotic symptoms secondary to other toxic or metabolic disorders4. Psychosis onset after ablative stereotaxic surgery5. Diagnosis of dementia made concurrent with or prior to a PD diagnosis6. Patients on clozapine due to the requirement of special safety monitoring required for clozapine, which will unblind the safety7. Patients taking part in another intervention trial concurrently. However, those withdrawn from another study or who have recently completed another intervention study will be eligible for inclusion if they satisfy study inclusion/ exclusion criteria. For pharmacological intervention, they will be eligible only after a sufficient period of washout (~ 5 times half-life of other study drug)8. Participant no longer able to report symptoms as a result of cognitive impairment9. Presence of depressive symptoms would not be an exclusion criterion. However, we would exclude those participants who may have severe depression10. Participants who answer "yes" on the C-SSRS Suicidal Ideation Item 4 or Item 5 (Active Suicidal Ideation with Some Intent to Act, Without Specific Plan, or Active Suicidal Ideation with Specific Plan and Intent) and whose most recent episode meeting the criteria for C-SSRS Item 4 or Item 5 occurred within the last 6 months, OR Participants who answer "yes" on any of the 5 C-SSRS Suicidal Behavior Items (actual attempt, interrupted attempt, aborted attempt, preparatory acts, or behaviour) and whose most recent episode meeting the criteria for any of these 5 C-SSRS Suicidal Behavior items occurred within the last 2 years, OR Participants who, in the opinion of the investigator, present a serious risk of suicide11. Any medical or psychological condition or social circumstances which may impair their ability to participate reliably in the study, or who may increase the risk to themselves or others by participating in the study12. Significant ocular pathology13. Concomitant medication that has a clinically relevant interaction with the CYP2C19 or CYP3A classes of liver enzymes will not be permitted from two weeks before inclusion until the end of the study. Examples of co-medication that will be not allowed will include CYP3A4 inhibitors (such as itraconazole, ketoconazole, posaconazole, fluconazole, erythromycin, clarithromycin, telithromycin, HIV protease inhibitors, nefazodone, telaprevir, boceprevir, imatinib, ticagrelor, voriconazole), CYP3A4 inducers (such as carbamazepine, efavirenz, nevirapin, etravirin) and CYP2C19 inhibitors (such as moclobemine, fluvoxamine, chloramphenicol, fluoxetine)14. Female patients who are pregnant or lactating15. Female patients of childbearing potential who are not willing to use a highly effective method of contraception for the duration of the trial to prevent pregnancy, or abstain from heterosexual activity*Females of childbearing potential are females who have experienced menarche and are not surgically sterilised (e.g. by hysterectomy, bilateral salpingectomy) or post-menopausal (defined as at least 1 year since last regular menstrual period). ** Highly effective methods of birth control are those with a failure rate of < 1% per year when employed consistently and correctly, e.g. combined (oestrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation: oral, intravaginal, transdermal; progestogen-only hormonal contraception associated with inhibition of ovulation: oral, injectable, implantable; intrauterine device (IUD), intrauterine hormone-releasing system (IUS); vasectomised partnerSexual abstinence is considered to be highly effective method only if defined as refraining from heterosexual activity from the date of consent until end of treatment and for 2 weeks after. The reliability of this method should be evaluated in relation to the duration of the study and the preferred and usual lifestyle of the participant16. Known hypersensitivity to CBD, gelatine or micro-crystalline cellulose17. Mechanistic sub-study only: Patients who have any contraindications to MRI, including: pacemakers, metallic foreign body in the eye, aneurysm clip in their brain, severe claustrophobia where patients would not be able to tolerate the scan etc
Below are the locations for where you can take part in the trial. Please note that not all sites may be open.
Dr
Katie
McGoohan
+44 (0)2078486997
canpdp.trialoffice@kcl.ac.uk
Prof
Sagnik
Bhattacharyya
+44 (0)7936545178
canpdp.trialoffice@kcl.ac.uk
The study is sponsored by King’s College London and South London & Maudsley NHS Foundation Trust and funded by Parkinson's UK; Grant Codes: G-1901.
Your feedback is important to us. It will help us improve the quality of the study information on this site. Please answer both questions.
Or CPMS 43972
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