Condition category
Nervous System Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Dr Montague Silverdale


Contact details

Salford Royal NHS Foundation Trust
Stott Lane
M6 8HD
United Kingdom
+44 1625 661782

Additional identifiers

EudraCT number number

Protocol/serial number

2007 Neuro 12

Study information

Scientific title

Antidyskinetic properties of topiramate: a double-blind, placebo-controlled trial in patients with Parkinson's disease and levodopa-induced dyskinesias


Study hypothesis

Levodopa therapy is effective for the motor symptoms of Parkinson's disease. However, around half of patients develop abnormal involuntary movements, or dyskinesia, after 4 - 6 years of treatment. Current treatment interventions for this are not satisfactory in all cases.

Topiramate administration will attenuate levodopa-induced dyskinesia in patients with Parkinson's disease (PD) without worsening parkinsonism.

Ethics approval

Leeds (West) Research Ethics Committee, 24/01/2008, ref: 07/H1307/205

Study design

Multicentre, randomised, double-blind, placebo-controlled, crossover study

Primary study design


Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet.


Parkinson's disease and levodopa-induced dyskinesia


This is a randomised, crossover study.

Topiramate group: start dose 25 mg/day orally (p.o.), to be up-titrated by 25 mg/day weekly to target dose of 100 mg/day in two divided doses. Participants to stay on maintenance dose for two weeks prior to assessment. Participants will attend having not taken usual morning medications, and response to these medications will then be assessed.

Control: placebo capsules, identical in appearance. To be titrated on same schedule as topiramate.

Following a two-week down-titration period, there will be a further two-week washout period before crossover.

Intervention type



Not Specified

Drug names


Primary outcome measures

Investigator-rated dyskinesia severity. To be scored by a blinded assessor from video recordings of participants, every 30 minutes for a total of 150 minutes. Dyskinesia to be rated at each time-point using a 5-point objective dyskinesia intensity rating scale, rating seven body parts (each limb, face, trunk and neck) with a maximum possible score of 28 at each time point. Timepoints of assessment: baseline (week 0), end of Arm 1 (week 6) and end of Arm 2 (week 16)

Secondary outcome measures

1. Investigator-rated parkinsonism. Unified Parkinson's Disease Rating Scale (UPDRS) part III to be assessed at 30-minute intervals during clinical assessment. Timepoints of assessment: week 0, 6 and 16.
2. Subject-rated dyskinesia severity:
2.1. Lang-Fahn Activities of Daily Living Dyskinesia Scale. Timepoints of assessment: week 0, 6, and 16.
2.2. Clinical Global Impression of change, assessed weekly during dose titration and at weeks 6 and 16
2.3. UPDRS Part IV. Timepoints of assessment: week 0, 6 and 16.
3. Effects on mood and activities of daily living:
3.1. UPDRS Part I, II. Timepoints of assessment: week 0, 6 and 16.
3.2. Geriatric Depression Scale-15. Timepoints of assessment: week 0, 2, 4, 6, 10, 12, 14 and 16.
4. Excessive daytime sleepiness: Epworth Sleepiness Scale. Timepoints of assessment: week 0, 2, 4, 6, 10, 12, 14 and 16.

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

1. Both males and females, no age limits
2. Patients with Parkinson's disease as defined by UK Parkinson's Disease Society Brain Bank criteria
3. Current use of levodopa, dose to be stable for one month prior to enrolment
4. Stable levodopa-induced dyskinesias

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Hypersensitivity to topiramate or its excipients
2. Prior surgery for PD
3. Hoehn and Yahr score of 5 when "off"
4. Dementia
5. History of nephrolithiasis, renal impairment, liver disease, glaucoma
6. Pregnancy and breastfeeding
7. Premenopausal females and males not using adequate contraception
8. Use of other antiepileptic drugs, carbonic anhydrase inhibitors, metformin, digoxin or illicit drugs

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Salford Royal NHS Foundation Trust
M6 8HD
United Kingdom

Sponsor information


Salford Royal NHS Foundation Trust (UK)

Sponsor details

Clinical Sciences Building
Stott Lane
M6 8HD
United Kingdom
+44 161 206 5137

Sponsor type




Funder type


Funder name

University of Manchester (UK)

Alternative name(s)

Funding Body Type

private sector organisation

Funding Body Subtype



United Kingdom

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes

09/05/2016: No publications found, verifying study status with principal investigator.