After another critical Huntington’s disease clinical trial proves negative, a time to embrace self-care and caregiving

 

A long-awaited clinical trial of a drug aimed at improving daily function  in the early stages of Huntington’s disease has produced negative results, Prilenia Therapeutics announced on April 25 at the American Academy of Neurology meeting in Boston.

 

According to Prilenia, the drug, pridopidine, failed to show improvement for trial participants on its primary and secondary measurements of symptoms (endpoints).

 

"Unfortunately, the failure of the PROOF-HD trial to meet its primary endpoint in preliminary analyses is a huge disappointment for the HD community,” Jody Corey-Bloom, M.D., Ph.D., the director of the Huntington’s Disease Society America (HDSA) Center of Excellence in San Diego, wrote me in an e-mail on April 25. “There was, however, some suggestion of benefit on other clinical measures, particularly a computerized assessment of motor function [a person’s movements], and I suspect we will see additional detailed analyses in the coming months.”

 

“We won’t sugar-coat this: the trial results were unfortunately negative,” the HD science site HDBuzz concluded. “The drug did not slow progression of HD as measured by the TFC [Total Functional Capacity]. Failing to meet its primary endpoint means that pridopidine will not get licensed by the FDA and other regulatory agencies.”

 

“The data obtained as part of the study remain useful and will be analyzed further for new insights they can provide,” Martha Nance, M.D., the HDSA Center of Excellence director in Minneapolis, wrote me. “We will not stop looking for better answers.”

 

Seeking a disease-modifying therapy

 

As an HD gene carrier who will inevitably develop symptoms, I had hoped to take pridopidine – if prescribed by a doctor – to help prevent or slow disease onset and maintain my daily activities. At 63, I have reached far beyond my HD-stricken mother’s onset in her late 40s. She died at 68.

 

Pridopidine would have been the first drug to potentially affect the progression of HD. Also, unlike drugs in other key trials that require spinal injection or direct injection into the brain (requiring an operation), pridopidine is a pill.

 

The news about pridopidine is the latest in a series of disappointing clinical trial news over the past two years. Last October, the highly innovative Triplet Therapeutics, Inc., had to shut down because of investor nervousness about the HD field. In December, Novartis had to end a program of developing its own pill for HD, branaplam, because of serious side effects in volunteers in a clinical trial.

 

PROOF-HD was a definitive Phase 3 trial. There are no other Phase 3 HD trials in progress for disease-modifying therapies.

 

Researchers remain hopeful that they will ultimately develop effective therapies. In January, Roche announced the start of GENERATION HD2, a second, less ambitious clinical trial of its gene-silencing drug tominersen. Other trials are in progress. This week, scientists and drug hunters focused on the cutting-edge developments at the 18th Annual HD Therapeutics Conference in Dubrovnik, Croatia (click here to read more).

 

Prilenia CEO and founder Michael Hayden, M.D., Ph.D., reporting the negative results for improvement in Total Functional Capacity in PROOF-HD participants at the HD Therapeutics Conference, April 27, 2023 (photo from HDBuzz)

 

Stepping back from advocacy

 

With the rest of the HD community, I have been riding the “clinical trial roller coaster” of emotional ups and downs in the quest for therapies.

 

I am also acutely aware of the passage of time – and that I may never get to participate in a clinical trial. GENERATION HD2, for example, restricts participation to ages 25-50. In the 30 years since the discovery of the huntingtin gene, we still have not seen a therapy to slow, stop, or reverse the disease. This month marks 25 years of my work as an HDSA volunteer advocate.

 

Recently, due to unforeseen circumstances unrelated to HD, I have had to step back from my advocacy, including this blog. My current challenges come on top of the juggling act that has characterized my fight against HD since my mother’s diagnosis in 1995 and positive test for the mutation in 1999.

 

So I have struggled to maintain my sense of meaning and purpose – crucial in slowing cognitive decline in HD. 

 

I have thus felt the need to concentrate on self-care. I believe there is wisdom in recognizing the importance of self-care – especially for someone like me facing a challenge for which science has yet to find an answer.

 

As I have learned, my first obligation is to my own health – remaining symptom-free and therefore fully available for my family, friends, and others I love and care for.

 

In this blog I have aimed for transparency about my health. For my own and the community’s benefit, I have sought to report accurately and thoughtfully on the quest for therapies, the endeavor to provide better care, and the many ramifications of HD (click here to read more).

 

Prioritizing diet, sleep, and exercise

 

So, as an advocate striving to be the best version of himself, I want to embrace self-care.

 

Last August and September, though fully vaccinated and having masked except for meals, I fought off an infection of COVID-19 caught in Boston while attending HD2022: Milton Wexler Biennial Symposium, sponsored by the HD-focused Hereditary Disease Foundation. I have been deeply concerned about COVID-19 because of the many instances of long COVID, the disease’s neurological symptoms, and the devastating impact on people in their 60s and older.

 

The pandemic has highlighted the need for self-care and caregiving.

 

To continue HD-free, I must prioritize the triad of a healthy diet, adequate sleep, and regular, vigorous exercise. I tell myself about swimming: in terms of health, “this is the most important thing you can do today.”

 

Recently, after challenges replacing my retired psychotherapist of 24 years, I began working with a new therapist – a profound form of self-care.

 

Self-care for me also includes continued participation in Enroll-HD and other HD research studies.

 

 Gene Veritas (aka Kenneth P. Serbin) swimming in his backyard pool (family photo)

 

Addressing deficits in care and caregiving

 

With the negative results from PROOF-HD and other recent trials, I am reminded of the debate and tensions over “care versus cure” that I witnessed at the start of my HDSA advocacy in the late 1990s and early 2000s. We need both. I saw my mother’s desperate need for care as HD devastated her and fought with fellow advocates to support the search for a cure.

 

As I age, and with the continued lack of effective therapies, the likelihood that I will not take a disease-modifying drug increases – as does, therefore, the likelihood that I will need caregivers. For HD gene carriers like me, improvements in caregiving will become essential.

 

As one key study has shown, serious deficits HD in care and caregiving remain, and plans for addressing this issue remain aspirational.

 

Most HD funding goes to biomedical research. Greater resources for HDSA and other patient advocacy organizations could help address the care and caregiving shortfalls.

 

Being patient and gentle with human fragility

 

Upon entering this world, we are all subject to illness, both genetic and non-genetic. The fight against HD, COVID-19, and other illnesses highlights our human fragility.

 

We are all potential caregivers and recipients of care, at various times in our lives.

 

I have found heart in the words of Pope Francis during his historic May 2017 audience with the HD community at the Vatican, which I attended with my family: “Fragility is not an ill, and disease, which is an expression of fragility, cannot and must not make us forget that in the eyes of God we are priceless. Disease can also be an opportunity for encounter, for sharing, for solidarity.”

 

As I patiently and gently await the recharging of my mental and spiritual batteries, I am mindful of my own – and others’ – fragility and the new opportunities for solidarity in achieving research progress and improved caregiving.

After other firms’ setbacks, Prilenia readies for readout on Huntington’s drug that improves daily function

 

August brought more difficult news for the Huntington’s disease community with the halting of yet two more clinical trials. However, Prilenia Therapeutics announced at a major research conference last week that it expects to obtain definitive results from a study of a drug proposed to improve function in the early stages of the disease.

 

Prilenia CEO and founder Michael Hayden, M.D., Ph.D., a leading HD scientist, reported that the Phase 3 clinical trial of pridopidine is on schedule, with administrators expected to release results early in the second quarter of 2023. (Click here for background on pridopidine, Dr. Hayden, and Prilenia.)

 

On August 25 Dr. Hayden provided a brief update on the trial, called PROOF-HD (PRidopidine Outcome On Function In Huntington Disease), at HD2022: Milton Wexler Biennial Symposium, sponsored by the HD-focused Hereditary Disease Foundation. It was held August 24-27 at the Royal Sonesta Hotel in Cambridge, MA.

 

If successful, the PROOF-HD trial will result in a landmark not just for HD, but neurodegenerative diseases in general. Its potential significance has increased because of the disappointing results from two important HD gene silencing clinical trials in March 2021 and the news this month that key trials by Novartis and uniQure had to stop dosing because of safety concerns.

 

In an August 27 interview with me, Dr. Hayden explained pridopidine’s benefits.

 

“It's the only drug that has showed some impact on stabilizing TFC [total functional capacity], keeping patients functional, keeping them managing their finances, keeping them at work, keeping them going for walks with their children and grandchildren, keeping them doing activities of daily living for longer,” Dr. Hayden said.

 

Analysis of pridopidine has demonstrated that patients taking the drug showed a slower decline in TFC. In early patients, pridopidine can maintain TFC and slow deterioration

 

Dr. Michael Hayden (left) confers with Peter McColgan, M.D., the clinical director for the HD program at Roche, during a break in the Milton Wexler Symposium (photo by Gene Veritas, aka Kenneth P. Serbin)

 

Neuroprotective effects

 

The earlier, revised analysis of pridopidine led to a “surprising but very welcome result,” Dr. Hayden continued. Pridopidine works as a “highly potent and highly selective sigma-1 receptor agonist.” An agonist is a drug that mimics a natural substance, while sigma-1 is “a molecular chaperone,” a chemical that helps proteins perform the important function of folding. He called pridopidine “the most potent and selective” sigma-1 agonist ever described.

 

In everybody’s cells, decreased sigma-1 has a negative impact on monitoring stress, including for the endoplasmic reticulum, a key organelle (subunit) that manages stress. In HD, this subunit experiences disturbances that cause an imbalance in the cell, Dr. Hayden said.

 

Overall, a reduction in sigma-1 makes neurodegeneration (slow and progressive loss of brain cells) get worse, Dr. Hayden explained.

 

However, pridopidine enhances sigma-1. The drug has “all in all neuroprotective effects,” by reducing cellular stress and even increasing the critical “connectivity” of the brain and the removal of “toxic products.”

 

Critically, pridopidine is “the only [HD] drug that has shown stabilization of neurofilament,” an important marker of disease progression, Dr. Hayden observed. An increase in levels of neurofilament, which makes up a brain cell's scaffolding, indicates dysfunction.

 

A Prilenia poster demonstrating the positive effect of pridopidine on total functional capacity and stabilization of neurofilament (photo by Gene Veritas)

 

A safe and tolerable drug

 

PROOF-HD seeks to confirm pridopidine’s efficacy so that it might be approved as a drug by the U.S. Food and Drug Administration (FDA).

 

“We submitted this to the FDA, and the FDA was hugely supportive,” Dr. Hayden said. Last November the FDA granted pridopidine a “fast track” designation to potentially speed drug approval, because HD is a “significant unmet need,” Dr. Hayden noted.

 

The designation “allows us to have a closer relationship with the regulators as we go through this process,” he said.

 

Despite the coronavirus pandemic, PROOF-HD began ahead of schedule in October 2020 and is on schedule to report results in about eight months. It recruited 499 clinical trial volunteers, more than the goal of 480, at several dozen sites in the U.S., Canada, and Europe.

 

So far, the standard safety monitoring board has found no reason halt the trial.

 

“So that's also encouraging that this is a very safe and tolerable drug,” said Dr. Hayden. 

 

A Prilenia slide with an overview of PROOF-HD, including the main goals (endpoints) (photo by Gene Veritas)

 

Seeking to prevent disease

 

In contrast with other top HD drug programs using brain or spinal injections, pridopidine is taken orally twice daily, “without any need for nursing care,” Dr. Hayden pointed out.

 

If PROOF-HD is highly successful, inviting a priority review by the FDA, Dr. Hayden said that pridopidine could become available for patients in mid-2024.

 

“My vision for pridopidine is that it could become a standard of care for neuroprotection,” Dr. Hayden stated in a January interview. “For diseases where we can define patients who are close to onset of a neurodegenerative condition, an oral therapy with a benign safety profile – which is what we are trying to establish in our current and planned clinical trials – could become a preventative treatment option.”

 

In a January 2021 Huntington’s Disease Society of America (HDSA) webinar, Sandra Kostyk, M.D., Ph.D, the co-principal investigator for PROOF-HD in the U.S., referred to pridopidine as a possible “disease-modifying intervention – something that slows the course of the disease.” The data indicate that early-stage HD patients could obtain “long-term beneficial effects” from an approved pridopidine drug for five years or more, she said.

 

A Prilenia slide about the advantages of small molecule drugs, the preferred method of treatment in HD. Pridopidine is in that category (photo by Gene Veritas)
 

An upcoming update, a caution, and hope

 

On September 7, HDSA will host a webinar further updating PROOF-HD and featuring Dr. Hayden, Dr. Kostyk, and Andrew Feigin, M.D., the trial’s principal investigator in the U.S. Click here to register.

 

“Of course, there's no certainty that this drug will be successful,” Dr. Hayden told me. “Forty percent of Phase 3 trials fail. So, we have a 60 percent chance. In a Phase 3 trial, things fail for all kinds of unexpected reasons, as sadly we've seen in the Huntington's field.”

 

Pursuing successful trials for pridopidine “has been a long struggle for everybody,” Dr. Hayden concluded. “This is hopeful, but we're not there yet. But hold on as we go on this journey as co-travelers in the attempt to find some way to moderate the course of this dreadful illness.”

 

(Future articles will cover other aspects of the Milton Wexler Symposium. Also see @HDBuzzFeed on Twitter and this article.)

 

Dr. Hayden (right) and Nicholas Caron, Ph.D., exchange ideas at the poster session of the Milton Wexler Symposium (photo by Gene Veritas).

With PROOF-HD in the lead, the Huntington’s disease drug pipeline is still ‘full of hope’ (Coping with disappointing clinical trial results – Part II)

 

Despite the recent disappointing news about two fundamental programs seeking Huntington’s disease treatments, significant drug-discovery initiatives proceed steadily. They include two major clinical trials: KINECT-HD, sponsored by Neurocrine Biosciences, and PROOF-HD, backed by Prilenia Therapeutics.

 

As reported in Part I of this two-part series and a previous article, Roche announced that it had halted dosing in its historic Phase 3 gene silencing clinical trial, followed by Wave Life Sciences’ revelation that a similar effort to reduce the level of mutant huntingtin protein had fallen short.

 

In all likelihood, these drug candidates – at least the current version of them – will not become HD treatments.

 

However, other candidates abound.

“Our pipeline is full of hope,” said George Yohrling, Ph.D., the chief scientific officer for the Huntington’s Disease Society of America (HDSA), in a March 25 webinar held to address the devastating clinical trial news. “Our pipeline is deep and diverse.”

 

The HD research community “has not put all their eggs” in the Roche “basket,” Dr. Yohrling explained. “We know what causes the disease, and it’s the expansion of the huntingtin gene and the expression of this mutant protein. There is a wide array of approaches that we are using to tackle that. We’re hopeful that one or many of them will prove efficacious and modify the course of the disease.”

 

Advancing programs

 

Although two Wave drug compounds failed in early-stage trials, the company plans to start a trial of a third compound later this year.

 

Both Roche and Wave are scheduled to make the first scientific presentations about their recent results this week at the greatly anticipated 16th Annual HD Therapeutics Conference, April 27-29, a virtual event because of the COVID-19 pandemic. The research community is confident that a deep analysis of these studies will guide its next steps in the quest for therapies.

 

Researchers and companies are investigating dozens of distinct designs for the type of drug used by Roche and Wave, an antisense oligonucleotide (ASO).

 

Using surgery to inject its drug directly into the brain, Uniqure has started the first-ever HD gene therapy safety trial in a small number of trial participants.

 

Triplet Therapeutics aims to start a Phase 1 clinical trial in the second half of this year of a unique ASO targeted at stopping the mutant huntingtin gene’s tendency for continued expansion with age (click here  to read more).

 

Genetic modification is not the only approach under study, however. Several other firms have Phase 2 programs in the works to treat symptoms and reduce disability due to HD, and Neurocrine expects to complete KINECT-HD – its Phase 3 trial of a chorea-reducing drug called valbenazine – by year’s end. Chorea is the involuntary movements that afflict many people with HD. (On KINECT-HD, also click here.)

 

Two similar drugs for chorea – Xenazine and Austedo – are the only HD drugs approved by the U.S. Food and Drug Administration (FDA). They do not stop progression of the disease.

 

A big goal: helping HD people function normally

 

A second major study, called PROOF-HD, is currently underway, led by the Huntington Study Group (HSG), and sponsored by Prilenia. This is a Phase 3 trial (the final step before a drug can be approved by the FDA) of a drug called pridopidine, which is proposed to improve function in people in the early stages of HD.

 

PROOF-HD stands for “PRidopidine Outcome On Function In Huntington Disease.”

 

The clinical trial investigators believe that, if tested successfully, pridopidine would help early-stage HD-afflicted individuals maintain the ability to function normally in five key areas: occupation/employment, managing personal finances, performing household chores, performing activities of daily life (such as bathing and dressing), and the ability to live in a home environment. These five domains comprise the Shoulson-Fahn Total Functional Capacity Scale (TFC), developed almost 40 years ago, and used daily in HD clinics and research studies since then.

 

“The bigger the effect, the better,” Prilenia CEO Michael Hayden, M.D., Ph.D., said in an April 1 interview about pridopidine with Evaluate Vantage. “But any significant change in TFC would be regarded as meaningful. There’s never been a drug that has had any impact on TFC.”

 

Dr. Hayden is one of the world’s foremost HD scientists (click here to watch our 2011 interview at the Therapeutics Conference.) Prior to founding Prilenia in 2018, Dr. Hayden served as the president of global R&D and chief scientific officer at Teva Pharmaceutical Industries, Ltd. from 2012-2017, where he oversaw ongoing research on pridopidine. He is also a professor at the University of British Columbia and a senior scientist at the Centre for Molecular Medicine and Therapeutics, having mentored over 100 graduate students.

 

In a January 28 HDSA webinar, Sandra Kostyk, M.D., Ph.D., a professor Ohio State University and the co-principal investigator for PROOF-HD in the U.S., pointed out that individuals’ Total Functional Capacity ranges from zero (severely reduced function) to 13 (full function). In early and mid-early HD, people on average lose about one point on the scale a year, she explained.

 

In later stages of the disease, TFC may be less reflective of the rate of decline, Dr. Kostyk continued.

 

A slide from the January 2021 HDSA webinar on the PROOF-HD trial illustrating the Total Functional Capacity Scale and the effect of  pridopidine (screenshot by Gene Veritas, aka Kenneth P. Serbin)

 

Stopping the house from burning down

 

As an HD gene carrier who saw his mother devastated by the disease, I have most feared losing my ability to function normally.

 

In three previous clinical trials of pridopidine, carried out between 2008 and 2018, both the original developer of the drug and Teva failed to achieve the goal of reducing HD persons’ difficulties with both voluntary and involuntary movements. At that time, scientists thought that pridopidine affected levels of dopamine, an important chemical in the brain affecting movements in both HD and Parkinson’s disease.

 

However, additional analysis (done after the trials) showed that patients taking the study drug showed a slower decline in TFC than expected from previous studies. “In early patients with Huntington disease we have shown that the functional capacity may be maintained,” Dr. Hayden observed in a January HSG podcast. “There also appears to be an improvement and less deterioration in patients with early HD.”

 

Referring to research conclusions published in the Journal of Huntington’s Disease last December and co-authored by Dr. Hayden and five others, he asserted that the stabilized TFC results were the “first time that this has ever been shown in any analysis for any drug. This was exciting.” Significantly, the FDA accepts TFC as a way of measuring drug efficacy in HD clinical trials, he added.

Those observations now require confirmation in PROOF-HD, Dr. Hayden said.

 

Also, he continued, pridopidine “appears to have beneficial effects around protecting neurons,” whatever the injury might be. The goal, he said, is to prevent these brain cells from dying – one of the major symptoms of HD.

 

“You want to treat them before they've died,” he explained. “If you're trying to stop a fire taking care of a house, you don't want the house to be burned down. And that's why treating early becomes effective because there are still injured neurons, but not dead neurons.”

 

In the HDSA webinar, Dr. Kostyk referred to pridopidine as a possible “disease-modifying intervention – something that slows the course of the disease.” The data indicate that early-stage HD patients could obtain “long-term beneficial effects” from an approved pridopidine drug for five years or more, she said.

 

That could buy valuable time for older asymptomatic individuals like me and the HD community in general as we await other gene-modifying or huntingtin-lowering drugs.

 

Prilenia: seeking to soothe the impact of disease

 

Dr. Hayden explained the name and goals of Prilenia: “Prilenia, which comes from pri, as in pridopidine, and lenia, which comes from the Greek, to sooth or to cure. It's an aspiration that we can have some impact on soothing some aspects of this disease and potentially others as well.”

 

Privately held and based in Israel and the Netherlands, in 2020 Prilenia raised $68.5 million to support PROOF-HD and also a Phase 2/3 trial in sufferers of amytrophic lateral sclerosis (ALS).

 

The ALS trial is currently enrolling participants at 54 sites across the US.

 

Pridopidine taken as a pill

 

For HD sufferers, Pridopidine has another major advantage: whereas ASOs so far have been injected into the spine and Uniqure’s drug has been infused via brain surgery, pridopidine in the PROOF-HD trial is very conveniently dosed in a 45-milligram pill – a hard gelatin capsule – taken twice daily (click here for official details of the trial). 

 

Pridopidine has been extensively studied in several previous clinical trials over more than a decade, with more than 1,300 people taking the drug, most of them with Huntington’s, Dr. Kostyk said. As a result, researchers have high confidence in its safety, she added.

 

Other HD research projects and biopharmaceutical firms are seeking so-called small molecule drugs that can enter cells easily and be taken as a pill.

 

A key receptor in the brain

 

Dr. Hayden and his colleagues now believe that the benefits of pridopine are due to its ability to activate the sigma-1 receptor (S1R). “It’s highly selective and fairly potent,” Dr. Hayden explained about the action of pridopidine on S1R in response to a question that I posed about the drug’s basic mechanism during his presentation at the 27th Annual HSG Meeting (held online) in October 2020.

 

Dr. Hayden observed further that ample data demonstrates that activation of S1R leads to protection of neurons. Deficiencies in S1Rs leads to disease. He cited the case of patients lacking the S1R gene, resulting in juvenile onset ALS.

 

“The activation of the sigma-1 receptor has multiple mechanisms of action that should lead to neuroprotection in HD and help stabilize cell function,” stated Dr. Kostyk, noting that S1Rs are plentiful in the striatum – the inner core of the brain where HD is especially devastating – and in the cortex, the large outer area of the brain in charge of thought, language, and consciousness.

 

“One could think of the role of S1R as being like that of a high school guidance counselor,” Martha Nance, M.D., director of the HDSA Center of Excellence at Hennepin HealthCare in Minneapolis, MN, wrote me in an e-mail. “When the receptor is turned on, materials, molecules, and traffic within the cell flow as it should, and the cell stays healthy, much as the counselor helps students in trouble to be safe, find resources to keep healthy, and stay in school. Supporting S1R early in the course of HD might help more brain cells to remain healthy and function well for longer.”

 

A relatively easy trial seeking practical results

 

Initiated last October, PROOF-HD investigators hope to enroll a total of 480 clinical trial volunteers by year’s end at 30 sites in the U.S. and Canada and 30 more in Europe. Over 15 months, half will get pridopidine, and half will get a placebo. Patients must have a diagnosis of HD, be 25 or older (no upper age limit), and have a TFC score of at least 7, in line with the project’s goal of testing the drug in the earlier stages of the disease.

 

Participants will undergo measurements of their TFC, cognition, quality of life, and motor symptoms (difficulties with voluntary and involuntary movements). They will also get blood and safety tests. All participants can take part in the potential extension of the trial, with everybody receiving the drug. Dr. Kostyk described PROOF-HD as an “easy” trial, with no brain scans or spinal taps (used in the Roche trial, for instance). The study design has been adapted to accommodate the challenges posed by COVID-19.

 

PROOF-HD emphasizes practical results. “What’s most important for us it to get an agent out that’s working,” Dr. Kostyk said, and “not necessarily” the kinds of measurements used in other trials in order to demonstrate how the drug works.

 

A separate trial might be designed later for later-stage HD-afflicted individuals, Dr. Hayden said.

 

For more information on PROOF-HD, click here or call 800-487-7671.

 

A potential major step forward

 

“Our overall goal is to get this agent FDA-approved as soon as possible so that we can start using it in individuals affected by Huntington’s disease,” said Dr. Kostyk. The more quickly patients enroll in the study, the sooner it will be completed, hopefully by late 2022 or early 2023.  Because this is a Phase 3 trial, if it is successful, the next step will be an application to the FDA for approval as a drug that doctors can prescribe.

 

Andrew Feigin, M.D., the HSG chair and principal investigator in the U.S. for PROOF-HD, said in the HDSA webinar that Prilenia has also shown interest in a possible future trial involving pre-symptomatic individuals like me.

 

Past skepticism about pridopidine focused on the lack of hard evidence that the drug could really slow HD progression (click here to read more). However, that debate came before the discovery of a clearer picture of pridopidine as a potential protector of neurons.

 

As will all clinical trials, the Huntington's community will be rooting for success in PROOF-HD. Although pridopidine may not cure HD, enabling people to have a few more years of normal daily function would be a major step in the quest to manage this complex disease.