Trial results
AI generated results summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
According to the results reported on ClinicalTrials.gov, this trial (NCT01590888) looked at a drug called PBT2 in people with Huntington's disease. A total of 109 people took part — 36 received the higher dose of PBT2 (250 mg), 38 received the lower dose (100 mg), and 35 received a sugar pill (placebo). The trial's main goal was to measure how many participants in each group experienced at least one unwanted or unexpected health event (called an adverse event) while taking the treatment. It also measured changes in thinking skills, movement, everyday functioning, behaviour, and an overall impression of how participants were doing. The reported data shows that, for the primary measure — the number of people who experienced at least one adverse event — 32 out of 36 in the 250 mg group, 30 out of 38 in the 100 mg group, and 28 out of 35 in the sugar pill group reported at least one such event. For the thinking skills tests, scores are expressed as "z-scores" — a way of comparing individual results to an average, where a higher number means a better result relative to that average. The reported change from the start of the trial showed a small positive shift for the 250 mg group (around +0.06 to +0.23 depending on the test grouping), while the 100 mg and sugar pill groups showed small negative shifts. For movement, the 250 mg group showed a small decrease in their score of −0.7 (lower scores mean less impairment), the sugar pill group showed −1.3, and the 100 mg group showed +1.3. Changes in everyday functioning were similar across all three groups (around +1.1 to +1.3). Behaviour scores changed by −2.3 for the 250 mg group, +0.7 for the sugar pill group, and +3.0 for the 100 mg group (where lower scores indicate less disturbance). The overall investigator impression score — which weighs perceived benefit against side effects — was reported as 1.31 for the 250 mg group, 1.28 for the 100 mg group, and 1.18 for the sugar pill group; all values above 1 indicate the investigator judged some therapeutic effect was present. These are the results as reported to ClinicalTrials.gov. They are not medical advice — always discuss what they mean for you with your doctor.
View full results on ClinicalTrials.gov ↗ · Read the linked publication on PubMed (PMID 25467848) ↗
These are the results as reported to ClinicalTrials.gov, not medical advice. Verify independently with the trial site and discuss what they mean for you with your doctor.
Phase 2 Huntington's Disease Trial, Completed
Who may be able to join
AI generated eligibility summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
Who might be able to join this trial:
- You are willing and able to sign a consent form agreeing to take part in the study.
- You have been diagnosed with Huntington's disease, including both the physical symptoms and a specific genetic marker (a CAG repeat number of 36 or higher).
- Your level of day-to-day functioning falls within a certain range, meaning you are not in the very early or very late stages of the disease (confirm with trial site).
- You show some level of cognitive (thinking and memory) difficulty, but not severe impairment, based on a standard thinking skills test.
- You are 25 years of age or older.
- If you are taking the medication tetrabenazine, you have been on the same dose for at least 3 months.
- If you are a woman who could become pregnant, you are using a reliable form of birth control; or you are a woman who cannot become pregnant.
- If you are a man who could father a child, you are using a reliable form of birth control; or you are a man who cannot father a child.
- You have a "study partner" (such as a family member or carer) who spends at least 2 hours a day with you, at least 4 days a week, speaks fluent English, and is willing to attend some study visits and answer questions about you.
- You are able to swallow capsules by mouth.
- You speak fluent English and have enough vision, hearing, and physical ability to complete the study tasks.
Who may not be able to join:
- You have a known allergy to the study drug (PBT2) or any of its ingredients.
- You have another brain condition that causes memory or thinking problems.
- You have a memory or thinking condition caused by a disease outside the brain (confirm with trial site).
- You have another condition that is causing significant problems with your thinking or memory, in the doctor's opinion.
- You have any serious uncontrolled physical or mental health condition, including a history of seizures, in the opinion of the study doctor.
- You have a serious heart, liver, kidney, lung, metabolic, or hormonal condition that could affect your ability to take part, in the opinion of the study doctor.
- Your kidneys are not working well enough, based on a blood test result at the screening visit (confirm with trial site).
- You have been diagnosed with cancer within the last 2 years before joining the study.
- You are currently pregnant or breastfeeding.
Important: Always verify eligibility with the trial site directly before applying.
Based on publicly available eligibility criteria from ClinicalTrials.gov. Verify directly with the trial site before acting. This is not medical advice.
Contact this trial
Principal Investigator: Ray Dorsey, Johns Hopkins University
Australian sites
Contact details sourced from ClinicalTrials.gov. Verify directly with the trial site before attending.
GP referral letter
Print a one-page summary to share with your doctor.
Trial details
Where this trial is recruiting
5 site(s) in Australia. Confirm current status and contact details directly with the trial site.
Primary endpoints
Safety and Tolerability of PBT2 in Patients With HD
Can't join this trial?
Data last synced from ClinicalTrials.gov: 28 July 2026. Trial status can change. Always verify current status directly with the trial site before making any decision.