Normal questions, asked by families and by people living with HD. Here is what the evidence actually shows.
These are the ones that come up most often — supplements people are already taking, trials half-remembered, treatments advertised online, and techniques in the news. The answers here follow the same rule as the rest of this site: what the evidence actually shows, including when the honest answer is it was tested and it didn't work, or nobody knows yet.
Several of the compounds below were taken seriously enough that researchers ran large, carefully designed trials to test them. That is exactly how it is supposed to work, and it means these questions have real answers rather than rumours — which is more than can be said for most things in this disease. Entries are listed A to Z; jump straight to whichever one you came for.
If you have been taking some of these for years. Many people have — often on a doctor's passing mention, or a recommendation from someone in a support group who meant well. That was a reasonable thing to do with what was known at the time. These were the most promising ideas of their moment; that is precisely why they were given large trials rather than ignored. Finding out now that a trial answered the question is not a reason to feel foolish.
Two practical points. Supplements like creatine or coenzyme Q10 are not medications that need to be tapered, so there is no urgency and nothing to undo — but it is still worth one conversation rather than a decision made off a web page, because a few of them interact with prescription drugs. And the most useful thing to do with this page is not to act on it alone: bring it to your next appointment as a list of questions.
Also filed under: fish oil → Omega-3 · gene editing → CRISPR · Q10, ubiquinone → Coenzyme Q10 · vitamin B3, NAD+ → Nicotinamide riboside · RP103 → Cysteamine
Broader questions: Do these trials apply to me if I'm not early-stage? · How do I judge whether a trial is worth joining? · Is there anything that actually does help?
Two phrases worth knowing before you start. A trial's primary endpoint is the one question it was designed to answer, chosen in advance; results on anything else are weaker evidence. Stopped for futility means independent monitors looked at the data partway through and concluded the trial was very unlikely to show a benefit by the end, so continuing would expose people to inconvenience and risk for nothing. It does not mean the drug was found to be harmful.
"What about CoQ10? I've been taking it for years."
Tested — no benefit foundThe 2CARE trial gave 2,400 mg of coenzyme Q10 a day, or placebo, to 609 people with early HD at 48 sites in North America and Australia, run by the Huntington Study Group. On 14 July 2014 the NIH's neurological institute stopped it for futility. The dose tested was well above what is usually taken by choice.
One detail worth stating plainly rather than burying: there were more deaths in the coenzyme Q10 group (7%) than in the placebo group (4%). The monitoring board attributed these mostly to the disease itself, and the difference was not statistically significant — meaning it is within the range that chance produces in a trial this size. So this is not evidence that CoQ10 is dangerous. It is a reason not to assume that something sold as a supplement is automatically harmless.
Bottom line: coenzyme Q10 was not found to help people with early Huntington's.
Sources: HDSA / Huntington Study Group closure announcement · ClinicalTrials.gov NCT00608881
"Does creatine help? I keep seeing it recommended."
Tested — no benefit foundCreatine was taken seriously. From 2009 to 2014, a trial called CREST-E gave high-dose creatine or placebo to 553 people with early symptomatic HD at 46 sites across North America, Australia and New Zealand, funded by the National Institutes of Health. The dose was escalated to 40 grams a day — worth noting, because that is roughly ten times what people typically take on their own — and continued for up to four years.
At the first scheduled interim analysis, the independent monitors concluded that continuing would not demonstrate a benefit, and the trial was stopped. The result, published in Neurology in 2017, was that creatine did not slow functional decline. Stomach and bowel side effects were more common on creatine, and more people withdrew from the creatine group (35%) than from placebo (26%). An analysis afterwards hinted that men might respond better than women; findings like that, picked out after the fact, are a starting point for a future study rather than a result, and they often do not hold up when someone tests them directly.
Bottom line: CREST-E found no benefit from creatine in early Huntington's, at a dose far higher than anyone takes by choice. A smaller dose is not a reason for optimism — it is a reason for less.
Sources: NIH summary of CREST-E · Hersch et al., Neurology, 2017
"Why can't they just use CRISPR to cut out the bad gene?"
Not yet tested in peopleIt is a reasonable question. Huntington's is caused by one known mutation in one known gene, which sounds like precisely the problem gene editing was built for.
The biggest obstacle is not making the edit — it is delivery: getting the editing machinery into enough of the right cells deep inside a living human brain. But it is not the only obstacle. An edit cannot be undone, so anything that goes wrong is permanent; the body can mount an immune response to the delivery system; edits can land in places they were not meant to; and there is a real design question about whether to silence only the faulty copy of the gene or both, since the healthy copy does useful work.
Where it stands: CRISPR approaches for HD are preclinical. HDSA's pipeline lists IG-HD01 from Incisive Genetics as preclinical, with a clinical trial targeted for 2027, alongside a second programme, LETI-101. Work published in 2026 includes a CRISPR nuclease designed to target huntingtin, and separately CRISPR editing of MSH3 — a DNA-repair gene tied to how fast the repeat expands — which reduced disease signs in mice. All of this is cell and animal work.
Bottom line: real, and moving. But no person with Huntington's has yet received a CRISPR therapy in a trial, the nearest stated target is 2027, and target dates slip.
Sources: HDSA pipeline · pan-HTT CRISPR nuclease, Molecular Therapy, 2026 · Somatic CRISPR editing of Msh3 in mice
"I read that cysteamine slowed HD by 25%. What happened to it?"
Benefit not shownThis one is worth walking through slowly, because it is a useful lesson in reading a press release.
CYST-HD was a Phase 2/3 trial of cysteamine (RP103) in 96 people in France — 18 months blinded against placebo, then 18 months in which everyone received the drug. The primary endpoint was not met. Motor scores declined about 32% more slowly on cysteamine at 18 months, but the result was not statistically significant (p=0.19), meaning it sits well within the range chance alone produces. A significant result did appear among patients who were not taking tetrabenazine — but HDBuzz, reporting at the time, noted that this subgroup had not been specified in advance, which makes it a lead for a future trial rather than a finding.
At 36 months the company reported 25% slower motor decline (p=0.18, not significant) and 23% slower loss of functional capacity (p=0.25, not significant), with one measure — an independence scale — reaching significance (p=0.008). In December 2015 it announced it would advance toward a registration study. That is where the "25%" figure still in circulation comes from. No confirmatory trial has since shown that cysteamine slows Huntington's, and it is not an approved treatment for the disease.
HDBuzz's assessment at the time was blunt and still holds: we do not yet have evidence that cysteamine makes HD better. The European Huntington Association's write-up was titled Looking Past the Spin.
Bottom line: a drug can look encouraging, generate genuine headlines, and still never be shown to work.
Sources: HDBuzz on the cysteamine results · European Huntington Association, "Looking Past the Spin" · Company 36-month release, December 2015 · Verny et al., Movement Disorders, 2017
"Someone told me methylene blue works for HD but was buried because it's cheap. True?"
Lab onlyPartly true, and importantly overstated.
The laboratory work is real. A 2012 study from Leslie Thompson's group found that methylene blue interferes with mutant huntingtin clumping, and was protective in test tubes, cultured cells, fruit flies and fast-progressing mice — though in flies it helped only when given early, and in mice it delayed rather than prevented symptoms. The interest has persisted: a rat study published in the journal Biology in October 2026 reported partial improvements in working memory and mitochondrial function, with no effect on several other measures, and described methylene blue as a promising but partial candidate.
What is missing is the part that matters most. As of October 2026 there is no registered trial of methylene blue in Huntington's disease, and none has been reported in the fourteen years since that 2012 paper. So there is no evidence it helps patients — only that it does interesting things in cells and rodents, which is also true of a long list of compounds that later failed in people. Creatine and coenzyme Q10, elsewhere on this page, both looked good in animals too.
On "buried because it's cheap," there is a real kernel. Methylene blue is an old generic, so no company holds a patent that would justify the cost of a large trial, and that genuinely does leave promising repurposing candidates untested — it is a real structural gap in how drug development is funded. But two scientific obstacles also sit in the way. It is not clear it reaches the human brain at the doses that worked in animals. And it turns urine and the whites of the eyes blue, which complicates running a proper placebo-controlled trial, since participants could tell which group they were in — solvable with careful design, but it adds cost and difficulty to a trial nobody is currently paying for.
Bottom line: "never properly tested, partly for unglamorous funding reasons and partly for hard scientific ones" is accurate. "Proven to work and suppressed" is not.
Sources: HDBuzz, "Dyeing to prevent dying?" · Sontag et al., Journal of Neuroscience, 2012 · Rat study, Biology, October 2026 · FDA drug safety communication on methylene blue
"Is NAC worth taking? I've seen it mentioned for HD."
Being tested nowNAC is an antioxidant, and unlike most things on this page it is currently in a real trial. NAC-preHD is a Phase 2 study run through Western Sydney Local Health District, enrolling 160 participants who carry the expansion but do not yet have symptoms, with clinical and imaging outcomes measured at three years.
Worth being clear about what that does and does not mean. A trial being underway is a sign that serious people think the question is worth answering properly — it is not a sign of an answer, and a registered trial is not an endorsement of the compound. No results have been reported.
Bottom line: the question is being asked properly for the first time. Waiting for the answer is not pessimism; trials are the only thing that has ever actually told anyone anything.
Sources: NAC-preHD trial record · HDSA pipeline
"What about NR, or the NAD+ supplements people talk about?"
Being tested nowNicotinamide riboside is a form of vitamin B3 that raises NAD+ levels in cells. It is being tested in the NAD-HD study: Phase 2, run by Oslo University Hospital, 2,000 mg a day against placebo, 120 participants, two years of treatment, recruiting since March 2025. The question it asks is the change in a combined score of Huntington's symptoms after 730 days.
As with NAC, a trial underway means the question is being taken seriously, not that there is an answer — and being listed as a trial is not an endorsement of the supplement. No results have been reported. Note also that the trial dose is high and supervised, which is not the same as buying a bottle off a shelf.
Source: NAD-HD, ClinicalTrials.gov NCT06853743
"Does fish oil help?"
Tested — no benefit foundA purified omega-3, ethyl-EPA (marketed as Miraxion), got as far as Phase 3. The TREND-HD trial gave 2 grams a day or placebo to 316 people with HD at 42 sites in the United States and Canada for six months. The result, announced in April 2007: no statistically significant difference from placebo on the primary endpoint or on any secondary measure. The drug was safe and well tolerated. It simply did not work for HD.
Smaller earlier data had looked promising in a subset of patients, and the large trial did not confirm it — a pattern that repeats on this page, and the whole reason large trials exist.
Sources: Amarin announcement, April 2007 · ClinicalTrials.gov NCT00146211
"A clinic says it can treat HD with stem cells. Should we go?"
Handle with careTwo very different things get called "stem cells," and keeping them apart is most of the answer.
The real research. There are genuine early-stage stem-cell programmes in HD. HDSA's pipeline lists Cellavita HD, tested in Brazil using cells derived from dental tissue; BrainStorm, which modifies a person's own bone-marrow cells in the lab; and Trailhead Biosystems. These are early, and HDSA notes that Cellavita's Phase 3 "has not been confirmed to have started, and its status remains uncertain." No stem-cell therapy is an approved treatment for Huntington's anywhere in the world. Cell therapies can and do get approved for other conditions — the FDA approved one for a complication of bone-marrow transplant in December 2024 — but none for HD.
The sales operation. Separately from that research, clinics sell stem-cell and "regenerative medicine" injections for cash, for serious neurological diseases. The FDA's consumer alert is direct: such products are illegally marketed, "have not been shown to be safe or effective," and may "have significant safety issues that put patients at risk." The FDA's list of conditions these are wrongly marketed for names multiple sclerosis, ALS, Alzheimer's, Parkinson's, epilepsy and stroke. Huntington's is not on that list, but the pattern is identical and HD families do get approached.
What actually distinguishes them is less tidy than it is usually made to sound, so it is worth being precise. Being asked to pay for the treatment itself is the single strongest warning sign — legitimate trials do not sell you the experimental therapy. But "there are no costs at all" is not the test either: taking part in a real trial can still involve travel, time off work, and routine care billed to insurance. And being listed on ClinicalTrials.gov is a record, not a seal of approval — registration does not mean a regulator reviewed the study or that it is scientifically sound. The reliable move is not to judge it yourself from a website: take the specific offer to an HD specialist or an HDSA Center of Excellence, or call HDSA at 1-800-345-HDSA, before you spend anything or travel anywhere.
Sources: FDA consumer alert on regenerative medicine products · FDA approval of remestemcel-L, December 2024 · HDSA pipeline
"What about trehalose?"
Lab onlyTrehalose is a sugar that entered HD research in 2004, when a mouse study in Nature Medicine found it reduced huntingtin aggregates and produced modest improvement. It has been studied in cells and animals since, and it is sold as a supplement, which is why the question comes up.
No controlled trial has established that trehalose benefits people with Huntington's, and no registered HD trial of it was found as of October 2026. There is therefore nothing to report about whether it helps people — in either direction.
Source: Tanaka et al., Nature Medicine, 2004
"Those trials were in people with early symptoms. I'm premanifest — or further along."
A fair question, and one that usually goes unasked. CREST-E and 2CARE both enrolled people with early symptoms. Strictly speaking, they answer the question for that group, at those doses. In principle a compound could help earlier, before much damage is done, or later, and not show up in a trial of early-stage patients. Timing genuinely matters in this disease — it is part of why huntingtin-lowering is still being pursued after the tominersen setback.
But two things keep that from being grounds for optimism. The doses tested were far above what anyone takes by choice, so the "maybe my amount is different" instinct points the wrong way. And "it might work in a group nobody tested" is a hypothesis, not evidence — it is the reason to run a trial, not a reason to take something in the meantime.
The honest statement: creatine and coenzyme Q10 were not shown to help people with early HD, and no one has shown they help anyone else with HD either.
The practical questions families ask about trials are rarely the scientific ones. A few straight answers.
You may get the placebo. In a two-arm trial that often means roughly a coin flip. This is not a trick — it is the only way to find out whether a drug does anything — but it is worth knowing before you build a year of hope on being treated. Many trials offer an open-label extension afterwards, in which everyone can receive the drug.
It asks something of you. Expect repeated visits, questionnaires, cognitive testing, blood draws, scans, and in huntingtin-lowering trials often lumbar punctures. Travel and time off work are real costs even when the study drug is free.
You can leave. Consent is not a contract. You can take the consent document home, read it with someone, ask for it in plain language, and withdraw at any point without giving a reason and without affecting your care.
Where to start. An HD specialist or an HDSA Center of Excellence will know which trials you are actually eligible for, which is usually a much shorter list than it first appears. Enroll-HD is a different thing worth knowing about: a global observational study with no drug and no placebo, which builds the long-term dataset nearly every HD trial design depends on. For many families it is the most concrete contribution available to them.
Sources: HDSA Centers of Excellence · Enroll-HD, ClinicalTrials.gov NCT01574053
Yes — and this deserves as much space as the disappointments above, because a page full of things that did not work can leave the impression that nothing is worth doing. That is not the case. The honest framing is that these things improve how people live with HD; none of them has been shown to slow the underlying disease.
Exercise and physiotherapy have actual clinical guidelines. In February 2020 a group of HD physiotherapy researchers published clinical recommendations in Neurology, with a plain-language summary from the European Huntington's Disease Network. They advise seeing a physiotherapist soon after diagnosis and roughly every six months — more often if walking, transfers or falls are a problem — and at least three sessions a week of 20 to 30 minutes of moderate exercise: aerobic work, strengthening or circuit training, regular walking, and practising transfers like getting in and out of a chair or bed. The guidance is careful about what this delivers: it may improve movement, endurance, breathing and getting around. It does not claim to slow the disease. It is still the best-supported thing on this entire page.
Specialist care changes daily life. An HDSA Center of Excellence coordinates neurology, psychiatry, physiotherapy, speech and swallowing, nutrition, genetic counselling and social work in one place. Chorea, depression, irritability, sleep, swallowing difficulty and weight loss all have treatments that genuinely work. These are not consolation prizes — for most families, most of the time, they are where the real available gains are.
Research participation. Enroll-HD and clinical trials are the mechanism by which the next answer arrives, and taking part is the one lever families hold over how fast that happens.
Sources: Quinn et al., clinical recommendations for physical therapy in HD, Neurology, 2020 · EHDN plain-language summary · HDSA
A pattern worth noticing. Creatine, coenzyme Q10 and omega-3 all looked promising in animals before they were tested in people, and none slowed the disease. That is not a reason to dismiss early science — early science is where every real treatment starts. It is a reason to treat "promising in mice" and "shown to help people" as genuinely different claims, and to be wary of anyone who blurs them, whether they are selling hope or selling a product.
A question that isn't here? If something is being asked in your family or your support group and it is not on this page, send it to [email protected] and it will be researched and added. Corrections are equally welcome — especially if something here is wrong.
Every entry on this page was verified against its cited sources on 16 October 2026.