A Phase 3 interventional study of Votoplam (blinded) and Placebo in Huntington Disease, sponsored by Novartis Pharmaceuticals. Recruiting at 117 sites in 27 countries. Open to participants aged 21 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-09-22.
Sponsored by Novartis Pharmaceuticals (part of Novartis) · Phase 3, Interventional, and Treatment
Help build ClinicalTrials.gg — short surveys, remote interviews or testing, in your language. Take part →
Among 138 studies in Huntington Disease with a site in United States — 21 open to participants now, 29 under way, 4 of them phase 3. Huntington Disease · United States.
Among the 138 studies in Huntington Disease with a site in United States, this one is the 2nd largest by planned enrollment of the 90 interventional ones that give a count, is one of 4 that started in 2026, is one of 14 in phase 3, reaches primary completion later than 22 of the 28 other live ones, and was the 135th registered.
293 studies on the registry are indexed under Huntington Disease; 54 are open to participants now.
Browse Huntington Disease studies →21 of the 138 studies in Huntington Disease with a site in United States are open now. Recruiting first, the newest first:
Prilenia · Sites in United States, Belgium, Canada and 9 more countries
Ages 23–65
Leslie Thompson · Sites in United States
Ages 18–65
Skyhawk Therapeutics, Inc. · Sites in United States, Argentina, Brazil and 7 more countries
Ages 25+
The University of Texas Health Science Center at San Antonio · Sites in United States
Ages 18–85
Ohio State University · Sites in United States
Ages 30–65
A study can be open while its sites in United States have not opened yet or have stopped. Only those recruiting at a site in United States →
Of the 43 Huntington Disease studies recruiting now, 19 (44%) set no upper age limit and 20 (47%) stop at 75 or younger; 5 take children under 18; 20 take healthy volunteers.
This study: 21 Years to 70 Years · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
138 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 25 · Phase 2 39 · Phase 3 17 · Phase 4 3
First in 1999; this study’s year is marked. 4 started in 2026.
By drug class, each counting the studies that test any of its medicines:
This study's planned enrollment of 770 is above the median of 40 across 207 interventional studies indexed under Huntington Disease.
Median enrollment 44 across the 90 interventional studies, 131 across the 48 observational. Of the 99 that completed or were terminated, 36 (36%) have results posted.
This tab as a report to print or save as PDF → With an account.
50 of 138 have an industry lead sponsor. The 10 most frequent:
This study is registered under Novartis Pharmaceuticals, one of the names counted as Novartis. Under that name alone:
Novartis Pharmaceuticals is the lead sponsor of 2,718 studies on the registry; 221 are open to participants now.
Of its 585 completed or terminated interventional studies of FDA-regulated products, 438 (75%) have results posted.
Novartis has 5 studies filed under Huntington Disease — fewer than ten, so there is no comparison to draw.
9 of the studies in Huntington Disease with a site in United States that are under way reach primary completion within a year, 1 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT04713982Phase 3Vanderbilt University Medical CenterImpact of Deutetrabenazine on Functional Speech and Gait Dynamics in Huntington Disease | 2027-06-30 |
| NCT06843252The University of Texas Health Science Center at San AntonioHome-based TDCS (Transcranial Direct Current Stimulation) for Cognitive and Behavioral Symptoms in Huntington's Disease | 2026-12 |
| NCT06475898Huntington Study GroupLongitudinal Endpoint Assessment of Disease Burden in HD | 2026-12 |
| NCT05326451The University of Texas Health Science Center, HoustonHome-based Transcranial Direct Current Stimulation Open Trial for Behavioral and Cognitive Symptoms in Huntington's Disease | 2026-12-31 |
| NCT03233646Duke UniversityRetinal Imaging in Neurodegenerative Disease | 2026-12-31 |
Add all 9 to your calendar (.ics) → With an account.
Among the 138 studies in Huntington Disease with a site in United States, from their registry updates:
This tab as a report to print or save as PDF → With an account.
The purpose is to assess safety and tolerability of votoplam and to determine whether votoplam slows disease progression in patients with early symptomatic Huntington's disease (HD) compared to the control arm.
HTT227 - current compound code (former code is PTC518 from PTC Therapeutics), HTT227 is Novartis code under Novartis sponsorship.
This study will have a variable double-blind treatment duration of up to 36 months. As part of the study design, not every participant will complete 36 months of treatment.
The study consists of 3 periods:
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Meets all of the following criteria:
Exclusion Criteria:
Serologic evidence for active viral hepatitis as indicated by:
History or current diagnosis of or cardiac abnormalities indicating significant risk of safety for participants such as:
Women of , defined as all women physiologically capable of becoming pregnant from menarche until becoming , unless they have had surgical bilateral oophorectomy (with or without hysterectomy), total hysterectomy or bilateral salpingectomy at least six weeks before taking study treatment. In the case of oophorectomy alone, the reproductive status of the woman needs to have been confirmed by follow-up hormone level assessment.
o WOCBP are excluded unless they are using highly effective methods of (failure rate \< 1% per year) while taking study treatment and for 8 months after stopping study treatment.
Other protocol defined inclusion/exclusion criteria may apply
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Votoplam (blinded) taken orally, randomized in a 3:2 ratio (Votoplam: Placebo)
Drug: Votoplam (blinded)
Placebo (blinded) taken orally, randomized in a 3:2 ratio (Votoplam: Placebo)
Drug: Placebo
Votoplam (blinded) active treatment
Also known as: HTT227
Placebo
Change from Baseline in cUHDRS score
The Composite Unified Huntingtons Disease Ratings Scale (cUHDRS) is an improved composite measure to assess multi-domain clinical progression in HD. The cUHDRS is a combined weighted score of measures of motor function (TMS), cognition (SDMT and SWRT) and overall functional capacity (TFC): cUHDRS = \[(TFC-10.4)/1.9 - (TMS-29.7)/14.9 + (SDMT-28.4)/11.3 + (SWRT - 66.1)/20.1\] + 10. In conjunction with one another, these measures provide a comprehensive, sensitive and specific tool for monitoring disease progression, with lower scores indicating more severe disease. cUHDRS score range from -8 to 25.
Time frame: Baseline, Month 36
Change from Baseline in UHDRS-TFC
The UHDRS-Total Functional Capacity (TFC) focuses on the Investigator's assessment of the participant's capacity to perform a range of activities including occupation, finances, self-care, domestic chores and activities of daily living. The responses are derived from interview with the participant and/or companion, if applicable. Scores range from 0 to 13, with higher scores representing better functioning.
Time frame: Baseline, Month 36
Change from Baseline in UHDRS-IS
The UHDRS-Independence Scale (IS) measures a patient's overall level of functional independence in activities of daily living. It provides a single score ranging from 10 (total dependence/bedbound) to 100 (no special care needed) in intervals of 10, with higher scores indicating better functioning. Scores can also be assigned in increments of 5 for intermediate levels of function.
Time frame: Baseline, Month 36
The time to decline in TFC score by at least one or IS score by at least 10
The UHDRS-Total Functional Capacity (TFC) focuses on the Investigator's assessment of the participant's capacity to perform a range of activities including occupation, finances, self-care, domestic chores and activities of daily living. The responses are derived from interview with the participant and/or companion, if applicable. Scores range from 0 to 13, with higher scores representing better functioning. The UHDRS-Independence Scale (IS) measures a patient's overall level of functional independence in activities of daily living. It provides a single score ranging from 10 (total dependence/bedbound) to 100 (no special care needed) in intervals of 10, with higher scores indicating better functioning. Scores can also be assigned in increments of 5 for intermediate levels of function.
Time frame: Baseline to end of treatment up to 36 months
Change from Baseline in UHDRS-TMS
The UHDRS-Total Motor Score (TMS) is the cumulative sum of the individual motor ratings obtained during the administration of the motor assessment portion of the UHDRS. It includes items related to eye movements, speech, limb movements (including hand taps and pronation-supination), dystonia, chorea, and gait/balance. Scores range from 0 to 124, with higher scores indicating greater motor impairment.
Time frame: Baseline, Month 36
Change from Baseline in SDMT
The Symbol Digit Modality Test (SDMT) is used to assess attention, working memory, psychomotor speed and visual perceptual processing. Participants are presented with a translation key of specific numbers paired with unique abstract symbols. Below the translation key is an array of symbols paired with empty spaces, the participant's task is to match the number for each symbol as quickly as possible in a given time frame. Scores are based on number of correctly paired items and range from 0 to 110, with higher scores representing better performance.
Time frame: Baseline, Month 36
Change from Baseline in SWRT
The Stroop Word Reading Test (SWRT) is a measure of processing and psychomotor speed. Participants are presented with a list or words (color names) printed in black ink and asked to read aloud as many words as possible within a set timeframe. Scores are based on the number of words read correctly and range from 0 to 60, with higher scores representing better performance.
Time frame: Baseline, Month 36
Percent change from Baseline in blood mHTT protein
The mutant huntington protein (mHTT) which is detectable both in blood and cerebrospinal fluid (CSF), represents a reliable biomarker for HD due to its direct involvement in disease pathology. Blood mHTT is a direct product of the pathogenic HTT gene mutation and represents a proximal marker of Huntington's disease (HD) biology.
Time frame: Baseline to steady state and up to 36 months in blood mHTT protein
Change from Baseline in serum NfL
Serum Neurofilament light chain NfL is a component of the neuronal cytoskeleton, released into CSF and blood after neuro-axonal damage, serving as a marker of neurodegeneration and disease progression in HD.
Time frame: Baseline, Month 36
Incidence and severity of treatment-emergent adverse events (TEAEs), serious adverse events (SAEs) and TEAEs leading to participant withdrawal
Number of participants with AEs and SAEs, including notable findings on physical examination, changes in vital signs, laboratory parameters, ECG, etc.
Time frame: Baseline to up to 36 months
Showing the first 100 of 117 sites across 27 countries. Choose a country and city above to see the rest.
Plan to share: Yes — Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations. This trial data availability is according to the criteria and process described on www.clinicalstudydatarequest.com
No publications or documents are linked to this record.
Started Mar 2026 (actual). Primary completion is estimated for Apr 2030, 48 months after the start.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Votoplam