A Randomized, Placebo-controlled, Tourette Syndrome Study.

This study consists of three phases: Screening/Washout Phase, Double-Blind Phase and Taper Phase.

SCREENING/WASHOUT PHASE: Your study doctor or his staff will review with you any medications that you are currently taking and may instruct you, if appropriate, to discontinue taking certain medications. Your study doctor or his staff will explain how long you need to stop taking each drug before you can start the study. Depending on the type of medications you may be taking, the Screening/Washout Visit (Visit 1 of the study) may have to be completed in two visits. The screening/washout phase may take up to 90 days. If you agree to participate, the study doctor or his staff will carry out tests to see if you are eligible for this study. At the Screening/Washout Visit, you will have a medical and psychiatric history review (including medications you have taken for treating Tourette Syndrome) and a physical examination (including sitting blood pressure, pulse, temperature, weight and height). A blood sample will be taken (approximately 2-3 teaspoons) and tested to rule out any abnormalities. You will be asked to give a urine sample that will be tested for drug use and, if you are a female that is capable of having a child, to ensure that you are not pregnant at the time of study entry. The pregnancy test must be negative for you to continue in the study. Additionally, you may not currently be breastfeeding to continue in the study. You will undergo a medical and psychiatric evaluation. You will be asked to answer questions using scales, including one that measures the severity of your symptoms of Tourette Syndrome and one that measures your symptoms, if any, of attention deficit hyperactivity disorder (A-D/HD).

TITRATION/MAINTANENCE PHASE: If you continue to qualify for the study after the Visit 1 tests have been reviewed by the study doctor or his staff and you have completed the washout phase, you will return to your study doctor's office for Visit 2. The length of time between Visit 1 and Visit 2 will depend on the kind of medications you are taking (and may need to stop before entering this study). At Visit 2, you will have your blood pressure, pulse and weight measured. You will be asked to answer questions for the same two scales that you completed at Visit 1. You are asked to return all medication bottles (even if empty, partially used or unused) to each study visit. It is very important for us to be able to check study drug compliance.

You will be asked questions about how you are feeling and if you have started taking any new medications or had changes in other medications you may be taking since your last visit.

If you continue to meet eligibility requirements for the study, you will enter the study. You will be assigned by chance to one of two treatment groups. You may receive either topiramate or placebo (an inactive substance). This makes the assessment of the study drug much fairer. The chances you are receiving the study drug versus placebo are 1 to 1 or equal (50% chance that you will receive topiramate and 50% chance that you will receive placebo).

The study will last approximately 10 weeks. You will begin the study by taking 1 tablet of study medication (topiramate 25 mg or placebo) in the evening. This will be Day 1 of the study. After one week of this phase of the study, your study medication dose will be increased to 2 tablets (topiramate 50 mg or placebo) one tablet in the morning and one in the evening. Your study medication dose may continue to be increased until you have reached the dose level the study doctor determines to be appropriate for you, or, you are taking a maximum dose of 200 mgs per day of study medication (topiramate or placebo). Your study doctor may adjust your study medication dose as necessary. Study medication will be provided in 25 mg tablets of topiramate or placebo. Medication is provided in child-resistant bottles. All bottles should be returned (regardless of whether they are partial, empty or full) at each visit. It is important that you follow your study doctor or his staff's instructions on when and how to take the study medication. You will be expected to visit your study doctor or his staff again on Day 28 (Visit 3), Day 56 (Visit 4) and Day 70 (Visit 5) after beginning treatment. At Visit 5 (Day 70), you will be given instructions about reducing your study medication gradually for the next week.

At each visit, you will have your blood pressure, pulse, temperature and weight measured. You will be asked how you are feeling and if you have started taking any new medications or had changes in other medications you may be taking. At Visits 3 and 5 you will be asked again to answer questions for all of the scales that you completed at Visit 2. At Visits 3, 4 and 5, the study doctor or his staff will complete the scale that assesses the severity of your condition. At Visits 3 and 5, the study doctor or his staff will complete one scale that assesses the severity of your Tourette Syndrome symptoms. At Visits 3, 4 and 5 you will have a urine pregnancy test performed again if you are a female capable of bearing a child. The test must be negative to continue in the study. You will have blood drawn again (approximately one teaspoon) at Visits 3 and 5 to make sure that your liver is functioning properly and that your electrolytes (blood chemistry measurements) are also within normal range. At Visit 5 you will have another physical examination.

You will be called weekly between Visits 2 and 3 (Days 7, 14 and Day 21 of the study) and Visits 3 and 4 (Days 35 and 42 of the study) on the telephone by one of the people working on this study. During these phone calls you will be asked how you are feeling, if you have had any changes in medications you are taking and how you are doing with the study medication.

TAPER PHASE: You will visit the study doctor or his staff again on Day 77 (Visit 6) after you have completely stopped taking the study medication. You must keep all medication packaging and any unused medication, and bring it back to the study doctor or his staff at each visit. At this visit, you will have your blood pressure and pulse taken and your weight measured. You will be asked again to answer questions for the scale that measures the severity of your symptoms of Tourette Syndrome. If you are a female capable of bearing a child, a urine pregnancy test will be performed. You will be asked how you are feeling and if you have started taking any new medications or had changes in other medications you may be taking.

Joseph Jankovic, Joohi Jimenez-Shahed and Lawrence Brown J. Neurol. Neurosurg. Psychiatry published online 1 Sep 2009; doi:10.1136/jnnp.2009.185348