Antipsychotic Augmentation With L-Dopa
Dopamine, a chemical in the brain, has been linked to schizophrenia for a number of years. More recently, there is evidence that certain areas affected in schizophrenia (e.g. motivation, cognition) may reflect too little dopamine, whereas symptoms like hallucinations and delusions have been linked to too much dopamine.
This study is designed to evaluate the safety, tolerability, and efficacy of giving L-dopa (Sinemet) to see if it will improve those symptoms related to too little dopamine. L-dopa has been approved for other medical conditions (e.g. Parkinson's disease) and works to increase levels of dopamine.
The investigators are linking this study with neuroimaging (fMRI) which will allows us to link any changes the investigators might find in clinical symptoms with changes in the brain. This information can prove useful in better understanding the mechanisms that account for these symptoms, as well as possible new treatments.
At present , treatments for these other symptoms that seem important in functional measures of outcome (i.e. deficit symptoms, including amotivation; cognitive symptoms) in schizophrenia have not proven particularly effective. It is hoped that L-dopa may provide a treatment that is more effective; going forward, this information would also be useful in drug development and future lines of investigation.
- L-dopa will prove effective in improving deficit (also called 'primary negative' e.g. amotivation) and cognitive symptoms in schizophrenia.
- It will be well tolerated and not increase risk of psychotic symptoms when administered in conjunction with their regular antipsychotic medications.
|Schizophrenia||Drug: levodopa/carbidopa (generic version of Sinemet)||Phase 2|
|Study Design:||Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
|Official Title:||Augmentation of Antipsychotics With L-Dopa (Sinemet)|
- SANS - Schedule for the Assessment of Negative Symptoms [ Time Frame: 8 weeks ]
- MATRICS-Consensus Cognitive Battery [ Time Frame: 8 weeks ]
- BPRS - Brief Psychotic Rating Scale [ Time Frame: 8 weeks ]
- SAPS - Schedule for the Assessment of Positive Symptoms [ Time Frame: 8 weeks ]
- NIMH-MATRICS Brief Negative Symptoms Scale [ Time Frame: 8 weeks ]
- CGI-S - Clinical Global Impression - Severity Scale [ Time Frame: 8 weeks ]
- QLS - Quality of Life Scale [ Time Frame: 8 weeks ]
- CDS - Calgary Depression Scale [ Time Frame: 8 weeks ]
- SAS - Simpson Angus Scale for Extrapyramidal Symptoms [ Time Frame: 8 weeks ]
- BARS - Barnes Akathisia Rating Scales [ Time Frame: 8 weeks ]
- AIMS - Abnormal Involuntary Movement Scale [ Time Frame: 8 weeks ]
- UKU - Udvalg for Kliniske Undersogelses [ Time Frame: 8 weeks ]Measures General Side Effects
- LUNSERS - Liverpool University Neuroleptic Side-Effect Rating Scale [ Time Frame: 8 weeks ]
- BIS-11 - Barrett Impulsivity Scale [ Time Frame: 8 weeks ]
- Y-BOCS - Yale-Brown Obsessive Compulsive Scale [ Time Frame: 8 weeks ]
- DAI - Drug Attitude Inventory [ Time Frame: 8 weeks ]
- fMRI - Functional Magnetic Resonance Imaging [ Time Frame: 8 weeks ]Changes in Regional Brain Activity
- SWN - Subjective Well-Being on Neuroleptics Scale [ Time Frame: 8 weeks ]
|Study Start Date:||September 2012|
|Study Completion Date:||January 2016|
|Primary Completion Date:||December 2015 (Final data collection date for primary outcome measure)|
Experimental: L-Dopa (Sinemet)
Augmentation of current antipsychotic treatment with oral L-Dopa (levodopa/carbidopa) up to 900mg daily for 8 weeks
Drug: levodopa/carbidopa (generic version of Sinemet)
Oral levodopa 900mg daily as tolerated.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01636037
|Centre for Addiction and Mental Health|
|Toronto, Ontario, Canada, M5T 1R8|
|Principal Investigator:||Gary Remington, MD PhD FRCPC||Centre for Addiction and Mental Health|