Combatting the pandemic, Roche also forges ahead with critical Phase 3 Huntington’s disease clinical trial

Using its expertise to combat a coronavirus pandemic that has left more than 180,000 people dead worldwide and a third of the earth’s people on lockdown, pharmaceutical giant Roche is also forging ahead with its Phase 3 clinical trial for the Huntington’s disease gene silencing drug RG6042, now known by the generic name tominersen.

The final step in a clinical trial program, Phase 3 tests the efficacy of a drug. A successful Phase 3 allows a pharmaceutical company to apply to regulatory agencies for permission to market the drug. In a time of “social distancing” and a shutdown of normal life, Roche and HD clinical trial administrators are seeking to mitigate the risks associated with the spread of COVID-19, the disease caused by the coronavirus.

In an April 20 letter to the global HD community, Roche announced that it had completed recruitment for the trial, GENERATION HD1. A total of 791 symptomatic volunteers across 18 countries have been enrolled, just ten fewer people than Roche projected after the trial got under way last year – almost 99 percent of the target.

“This achievement is a result of the HD community’s commitment from the beginning, and we are very grateful to all trial participants, their families, the clinical trial sites and staff, and the broader HD community who have supported the design, initiation and recruitment phases of the study,” Roche global patient partnership directors David West and Mai-Lise Nguyen stated in the letter.

West and Nguyen reassured the community that “tominersen studies are ongoing at clinical trial sites around the world,” and, in collaboration with local health authorities, “ensuring patient safety and data integrity throughout the studies given the ongoing impact of COVID-19.”

On February 27, Roche announced the generic name for its HD gene-silencing drug candidate RG6042, formerly known as IONIS-HTT_Rx, developed by Ionis Pharmaceuticals, Inc. With assistance from Roche, Ionis ran the successful Phase 1/2a trial for the compound, shown to be safe and tolerable in trial participants. It also lowered the amount of mutant huntingtin protein, a major suspect in the disease, in volunteers’ cerebrospinal fluid. (Slide courtesy of Roche.) 

Aiming to analyze data in 2022

“Given the dynamic situation with COVID-19, we decided to close recruitment at 791 participants globally in order to avoid additional pressure on clinical trial sites who were screening potential participants,” they added, noting that the number of participants is “sufficient” to assess tominersen’s efficacy.

Roche is “working closely with the research teams, trial sites and local authorities to reduce any new risks posed by COVID-19 and ensure the trial can continue as long as it is safe to do so,” the letter stated. Roche advises participants to “discuss individual circumstances with their respective study sites.”

“Where patients and families can no longer go into [the] hospital to receive treatment or assessments, research teams will be in close contact over the phone to monitor their health and discuss any potential adverse events or any other issues,” the letter added.

Roche expects to complete the trial and start analyzing data by 2022, after each of the volunteers has completed the 25-month program involving intrathecal (spinal) injections of tominersen or a placebo, tests, medical evaluations, and digital monitoring, West and Nguyen stated.

If tominersen demonstrates efficacy and safety, Roche will submit applications to national health authorities to obtain approval as a treatment.

“During these exceptional times, we continue to consider how we can best support the community and welcome any suggestions,” the letter concluded.

In an April 21 e-mail to me, West noted that GENERATION HD1 recruitment was “completed within expected timelines,” unaffected by the COVID-19 crisis. In line with plans announced last October, Roche will also extend the study to China “as soon as possible,” West added.

Combatting COVID-19

The April 20 statement on GENERATION HD1 followed a general statement by Roche on March 19 discussing the March 11 announcement of the pandemic by the World Health Organization and the company’s efforts to combat it.

“We recognise that the public and private sectors across the globe need to work together to help effectively manage this developing situation,” said the statement, noting that Roche was engaged in developing a COVID-19 “diagnostics test which was granted Emergency Use Authorization by the U.S. Food and Drug Administration.”

Scientists, physicians, and public officials have stated repeatedly that vastly increased testing for the virus is needed in the battle against the pandemic.

Roche also confirmed initiation of COVACTA, a global Phase 3 clinical trial to evaluate the safety and efficacy of its rheumatoid arthritis drug Actemra/RoActemra in treating patients with severe COVID-19 pneumonia. The study started to enroll patients on April 3, with a target of 330 globally, including the U.S., Canada, and Europe.

Roche is also examining other drugs in its portfolio for potential testing to treat COVID-19.

(Click here to read more on Roche’s efforts against the coronavirus.)

A key supplementary trial

The February 27 announcement of the generic name tominersen took place at the 15th Annual Huntington’s Disease Therapeutics Conference, sponsored by CHDI Foundation, Inc., in Palm Springs, CA. (For an overview of the conference, click here.)

Scott Schobel, M.D., M.Sc., Roche’s associate group medical director and medical leader of the GENERATION HD1 effort, introduced the name when presenting the preliminary results of the so-called open label extension study (OLE) study of the compound. For 15 months, Roche continued to give the drug to all of the 46 participants of the successful Ionis trial, completed in December 2017. That same day, Roche posted the slides of Dr. Schobel’s presentation on its website.

The OLE reinforced the findings of the Phase 1/2a trial, which showed tominersen to be safe and tolerable in trial participants. Tominersen also lowered the amount of mutant huntingtin protein, a major suspect in the disease, in volunteers’ cerebrospinal fluid.

Also, when still in progress in early 2019, the OLE led Roche to temporarily halt GENERATION HD1 to redesign it in line with the OLE’s promising early data. 

In the original GENERATION HD1 design, participants would undergo monthly spinal tap (lumbar puncture) procedures over 25 months. One-third of participants would receive tominersen each month and one-third every other month. Another third would get a placebo.

In the updated trial, which resumed in June 2019, Roche decreased lumbar punctures to once every other month over the same period of time. In this revised design, one-third of participants are receiving tominersen every other month and one-third every four months. Another third will receive a placebo every other month. (Click here to read more.)

Less frequent dosing eases the burden on participants, their families, and clinical trial administrators.

The OLE also investigated potential biomarkers (signs of the disease and drug efficacy) for use in GENERATION HD1.

The OLE formed part of Roche’s strategy for skipping the usual Phase 2 trial to test efficacy and entering directly into Phase 3 to confirm efficacy in a larger population (click here to read more).

Scott Schobel, M.D., M.Sc., presenting open label extension study data for tominersen at the 15th Annual HD Therapeutics Conference (photo by Gene Veritas)

The ‘ultimate’ question: efficacy

After his presentation, Dr. Schobel met briefly with HD advocates to discuss his presentation and GENERATION HD1.

For the HD community, the takeaway message was the OLE’s confirmation of a less frequent dosage, and its helpful data for GENERATION HD1. Except for one person who decided to drop out to take a trip around the world, all of the OLE participants had continued taking the drug, putting them now at 20 months of follow-up, he explained.

Roche has great “confidence” in the sufficiency of the less frequent dosing in GENERATION HD1, Dr. Schobel emphasized.

With the OLE, Roche has “been able to learn” and apply it directly to GENERATION HD1 “in a way that we couldn’t have done if did a more traditional drug development path, which we feel great about,” he said.

What remains is the “ultimate” question: will tominersen be an effective treatment?

“We’re well-positioned with GENERATION HD1 to answer that question,” Dr. Schobel concluded.

If the trial is successful, tominersen will become the first treatment to slow, halt, and perhaps even reverse the symptoms of Huntington’s disease. 

(I hope to report soon on other ways in which COVID-19 has impacted the HD community and research.)

(Disclosure: I hold a symbolic amount of Ionis shares.)

Giving back during the COVID-19 pandemic

Many advocates for Huntington’s and other rare diseases work passionately and selflessly for their causes.

Now, as the coronavirus pandemic rages, more and more people around the globe want to give back. 

We are all witnessing the testimonies of the doctors, nurses, and other healthcare workers who offer front-line care for the patients hit with COVID-19, the disease caused by the virus.

As a Huntington’s gene carrier who lost his mother to the malady, I, too, want to help – in part because the crisis has postponed or forced online so many aspects of the HD cause (more on this in an upcoming article).

HD activists can and should do their part to help alleviate this crisis!

Preparing for a surge of patients

Worried about the flood of reports about shortages of personal protective equipment (PPE), I reached out to Yale University class of 1982 colleague and freshman roommate Peter S. Kieffer, M.D., an emergency room pediatrician, to see if I could help, perhaps by organizing an online campaign to support him and his institution. Dr. Kieffer works at HSHS St. John’s Hospital in Springfield, IL. An assistant professor at the Southern Illinois University School of Medicine, he also advocates for the chronically mentally ill through Independence Center. 

In 2014, after decades out of touch, Dr. Kieffer wrote in an e-mail that he had discovered this blog and my family’s struggle against HD.

“My heart goes out to you and your family as I have been long aware of the challenges of Huntington's disease, its genetic transmission, and the implications of early testing but have never known anyone personally with the diagnosis,” Dr. Kieffer wrote.

Since then, he and his family have donated generously to the Serbin Family Team in the annual Hope Walk of the San Diego Chapter of the Huntington’s Disease Society of America (HDSA). Several years ago, they visited us during their vacation in the area.

In his response to my March 28 e-mail, Dr. Kieffer explained that “physicians in rural Illinois have had more time to prepare for COVID-19 than our colleagues in big cities.”

“Numbers were small, now cases are becoming more frequent, and we are preparing for a surge in the next few weeks which could very easily surpass the ICU bed and ventilator capacity of our two hospitals,” he wrote. “However, Governor [J. B.] Pritzker's early shutdown may help blunt that curve. Although COVID-19 typically sickens children with less severity, they could still pass it to a white-haired pediatrician like myself! Fortunately, we still have enough PPE for what we need.”

So far, Dr. Kieffer has treated a young child who was a “Patient Under Investigation,” although tests have not yet confirmed COVID-19 in any of his patients, he wrote in an e-mail today.

Dr. Kieffer agreed to contact me should his institution need aid. I know that I personally cannot send PPE or medical equipment, but raising awareness about the local predicament and raising funds could be a way to assist.

Peter S. Kieffer, M.D. (photo by Southern Illinois University School of Medicine)

Donating critically needed blood

There are other ways I - and you - can help now.

After seeing an American Red Cross blood drive appeal on TV a couple weeks ago, I scheduled a donation for March 30. 

Last week, I suspended my minimal meat diet to raise the iron levels in my blood, as recommended by a Red Cross employee, who set me up for a “power red” donation (double the number of red blood cells).

That employee also told me of a critical shortage of blood, as reported by the Red Cross and in the media (click here to read more).

At the donation center, an employee took my temperature at the door, to make sure I had no fever and, therefore, possible COVID-19 symptoms. Donors were spaced about eight feet apart, to avoid contamination, and the nurses and other workers wore not only the typical gloves, but also masks.

Unfortunately, in a pre-donation pin-prick blood test, I fell just shy of the necessary iron level for a power red.

However, I was able to make a simple “whole blood” donation.

Gene Veritas, aka Kenneth P. Serbin, at an American Red Cross blood donation center in San Diego (photo by Gene Veritas)

Running risks for the common good

On the way home I thought: in any public place, we all run the potential risk of contracting the coronavirus, even at a facility like the Red Cross. 

I washed my hands very thoroughly, twice at the facility, then again at home. None of the donors, nor I, wore a mask. However, I may on future trips to public places, given the increasing number of reports about their effectiveness in blocking droplets that might contain the virus.

Like so many other HD gene carriers, I’ve spent many moments monitoring myself for symptoms. Now, I’ve started doing that for the virus.

However, physicians like Dr. Kieffer, first responders, grocery store workers, and so many others risk their health daily for the common good.

We all need to embrace the spirit of Dr. Kieffer’s words to me, echoing one of the signs at the Red Cross: “Thanks so much for your life-giving donation!”

Above, Gene Veritas' blood pack, and below, Gene Veritas in a donor chair at the American Red Cross (photos by Gene Veritas)

In times of crisis, Huntington’s and other chronic disease communities provide examples of fortitude

For individuals and families facing Huntington’s and other chronic diseases, daily living often seems like nonstop crisis. These communities, including selfless caregivers, have demonstrated great fortitude.

The current coronavirus pandemic adds another giant, unknown layer to the kind of challenges and suffering many in these communities are already accustomed to.

The country’s reaction to the pandemic and the shutdown of daily routines starkly reminded me of the national climate in the months following the September 11, 2001, terrorist attacks on New York City and Washington, D.C. Resulting in 3,000 deaths, 9/11 led to a temporary grounding of all domestic flights, the fear of subsequent attacks (including nuclear), and panic regarding other, unrelated terrorist threats such as the deliberate spread of highly dangerous anthrax bacteria. The economy also suffered serious long-term effects.

Members of the San Diego Chapter of the Huntington’s Disease Society of America (HDSA), in the bewildering days after 9/11, held a previously planned fundraiser and got ready to hold its first Celebration of Hope Gala.

With so many other, urgent demands on potential donors, we feared people might not remember our needs.

Later that fall, in an editorial in Conquest, our chapter newsletter, I wrote the following:

On September 20, less than two weeks after the crisis, members of the public and local organizations participated in the Third Annual Indy Go-Kart Challenge to raise funds for the cure of HD. Then, on October 11, the one-month anniversary of the attack, several hundred San Diegans took part in the Celebration of Hope Dinner to assist the Center of Excellence for Family Services and Research at the University of California, San Diego. We raised tens of thousands of dollars at these events. Elsewhere in the country other HDSA events went on as planned.

In this manner HDSA and its supporters have sent a resounding message that generosity and compassion are far stronger than the hateful politics of terror. We will move ahead, no matter what the odds are against us. This is the American spirit.

Unprecedented impact on daily life

So far, the coronavirus pandemic has had an unprecedented impact on the United States, with schools, universities, and many other institutions closing or switching to remote, online operations. As of March 15, at least 65 people had died in the U.S., with worst-case scenarios projecting 200,000 to 1.7 million deaths.

The pandemic has changed my workplace unlike any earlier tragedy. After 9/11, no classes were cancelled by my employer, the University of San Diego (USD). In 2003, the devastating Cedar Fire in San Diego County left 15 dead, destroyed 2,820 buildings, and charred more than 280,000 acres. In response, USD shut down for just two weeks and finished the semester normally, with everybody back on campus.

Now, because of the virus, USD has cancelled classes this week and will finish the semester (eight more weeks, plus final exams) online. The University of Pennsylvania, where my HD-free daughter Bianca studies, will do the same. My wife and I are worried that Bianca will not be able to make it home in time before potential travel restrictions.

Each hour, we learn of more victims of the virus and further curtailment of life as we know it.

Impact on the HD community

The global crisis has also impacted the mission of HDSA and individual HD families.

On March 13, HDSA CEO Louise Vetter sent an e-mail to “friends of HDSA” announcing that the organization “holds the well-being of our families, volunteers and staff as our top priority” and will therefore postpone “ALL local HDSA events (educational & fundraising) nationwide” until April 30. That complies with public health recommendations to curtail public gatherings to slow the spread of the coronavirus.

According to Vetter, HDSA still plans to hold its 35th Annual Convention in New Orleans, June 4-6, but will continue to follow the guidance from the Centers for Disease Control, World Health Organization, and state and local health agencies.

HDSA’s national headquarters in New York City is closed. However, the entire staff is working remotely and has the resources “to continue the uninterrupted support of our mission during this time,” Vetter assured.

The Huntington’s Disease Youth Organization postponed its May 2020 international congress in Glasgow, Scotland, to March 2021.

I have accepted an invitation to deliver the keynote address at the 37th National Conference of the Huntington Society of Canada in November, but have been told to hold off on reserving flights until the pandemic’s long-term effects become clear.

Visiting the afflicted

For one HD community member and blogger, Mandi, 33, the pandemic meant that on March 12 she could not visit her 58-year-old HD-stricken father, Danny, at the Missouri nursing home where he resides.

“They are locking all doors for the safety of people there,” wrote Mandi, a dedicated caregiver and herself at risk, but untested, for HD. “Was my first reaction sad I couldn’t see my dad? Sure, but I immediately checked myself. I realized my own selfish want to see my dad was tiny in comparison to keeping the people in the nursing home safe because who knew if I was a carrier since you can have it for over a week and not show symptoms.”

Mandi pointed out how the nursing home’s restriction is “terrifying for those of us with possibilities of losing family.” She wants “to do everything in my power to protect him as I always have.”

However, she concluded: “Until we really know what we are dealing with let’s just take the precautions seriously.”

Danny (left) and Mandi (family photo)

Especially resilient

With the coronavirus pandemic, the world can learn from the example of the HD community and our generous supporters.

We in the HD community, and other neurological disease groups, face relentless adversity. HD grinds down the brain, leaving the affected like my late mother unable to walk, talk, or care for themselves. Caregivers like Mandi and my late father are true “HD warriors.” 

However, because of this, we have developed a very realistic view of life.

“We are all in a race to death, but people at risk for life-shortening diseases know that their time to the finish line is painfully fast and troubled,” I wrote in 2009 in an article titled “HD: hurtling towards death.”

At the same time, we also have a special appreciation for the “preciousness of life.”

Confronting HD makes us especially resilient. I am hopeful that the HD community will successfully meet the challenges of the coronavirus pandemic and, as in facing past challenges, become even stronger.

CHDI head scientist Pacifici: ‘hang on in the learning roller coaster ride of Huntington’s disease clinical trials’

With historic clinical trials now aiming for the first effective treatments for Huntington’s disease, affected individuals and their families need to clearly understand the news about these efforts and their implications.

That critical recommendation was offered by Robert Pacifici, Ph.D., the chief scientific officer of the nonprofit HD-treatment-seeking CHDI Foundation, Inc., during an interview on the last day of the organization’s 15th Annual HD Therapeutics Conference, held February 24-27 in Palm Springs, CA.

“Getting to this stage – which we’ve all so been hoping for – is still a bit of a roller coaster ride,” Dr. Pacifici told me. “You have to be able stay in our seats and weather the ups and downs. I think we’re well-poised for some great news, as some of these trials hopefully report out. Even a whisper of efficacy would be just amazing.”

However, there will also be “disappointments, where, despite our best attempts, some of the things that showed so much promise didn’t end up meeting their endpoints,” he cautioned. “But it’s going to be a learning roller coaster. So hang in there. Don’t lose hope.”

The HD-affected (and their caregivers) should keep informed about the trials by consulting their physicians, attending meetings of patient organizations such as the Huntington’s Disease Society of America (HDSA), and keeping abreast of developments in such sources as HDBuzz.net and this blog, Dr. Pacifici advised.

Become knowledgeable, he urged, “so that you are not disproportionately spooked or elated when these bits of information come out.”

Featured conference speaker Christopher Austin, M.D., the director of the National Center for Advancing Translational Sciences/National Institutes of Health, presents part of the Drug Discovery, Development and Deployment Map the research and pharmaceutical community must navigate in today's complex and challenging scientific world (photo by Gene Veritas, aka Kenneth P. Serbin).

‘Genuinely interested’ in treating HD

Dr. Pacifici began the interview noting the excitement generated by the conference and within the HD field, with a record 380 participants, overflow seating, and more than 100 people turned away. However, CHDI’s goal ultimate goal is not to host well-attended conferences, but to stop HD, he emphasized.

“There are that many people who are genuinely interested in presenting the results and learning about the incredible developments that are unfolding in Huntington’s disease drug discovery and development,” he said of the response to the conference.

Dr. Pacifici also noted the very high quality of the presentations, in comparison with the early years of the event. 

“We’re batting 1,000 this time – every single talk very relevant,” he observed.

Considered science fiction a decade ago, the new technologies applied in HD research are transforming the field and allowing for a more thorough analysis of cells in the quest to understand the disease, he added.

Dr. Pacifici cited the example of whole-genome sequencing on individual brain cells, which permits the reading of the DNA sequence of “every single gene in there, and doing that thousands of times.” 

You can watch my interview with Dr. Pacifici in the video below. For my video album of the conference, please click here (and check back in the coming days as I add videos).

Hang on in the 'learning roller coaster ride' of Huntington's disease clinical trials from Gene Veritas on Vimeo.

New understanding of the protein

Dr. Pacifici also discussed new research into the huntingtin protein presented at the conference. Such research suggests that the protein might have a key role in maintaining the integrity of the huntingtin gene and also in the way the gene expands over time (known as somatic expansion), which researchers now see as a key driver of the disease (click here to read more).

With this potential new finding, a single drug might be developed to counteract the mutant protein by both reducing its quantity and preventing it from causing somatic expansion, he speculated.

He pointed in particular to the presentation by Jeffrey Carroll, Ph.D.

A possible key biomarker

Dr. Pacifici also commented on the discussion around phosphodiesterase-10 (PDE-10). A PDE inhibitor was seen as a potential “Viagra for the brain” but ultimately showed no improvement in a clinical trial run by the drug giant Pfizer.

However, PDE-10 might still play a role for the HD community as a biomarker (sign of disease and/or effect of a treatment), Dr. Pacifici said.

“It is pretty uniquely expressed in the neurons that we know are affected by Huntington’s disease, the medium spiny neurons,” he explained. 

If PDE-10 decreases in HD because the gene is shut down or cells die or some combination of both, and “if you had a molecule that bound to PDE10 and sent out a signal, then you could know how much PDE10 was in that brain, and if it was declining, that would mean that the disease was progressing.” Similarly, with an effective therapy, “you would see PDE10 levels going up,” Dr. Pacifici added.

The U.S. Food and Drug Administration is unlikely to approve a drug based solely on evidence from a biomarker, because it needs to see actual clinical benefits in patients, Dr. Pacifici said. However, the biomarker could give a drug maker the “confidence” that the “intervention is doing its job biologically and now it’s worth waiting for the clinically meaning outcome.”

(The presentation by Steven A. McCarroll, Ph.D., of the Harvard Medical School, included discussion of the role of PDE-10.)

Above, Dr. Steven McCarroll answers a question from the audience after his presentation on single-cell analysis of HD biology. Below, McCarroll lab researchers Nora Reed (left) and Christopher Mullally with the lab's poster on single-cell analysis, which took second prize in the poster competition (photos by Gene Veritas).

The terrifying truth about drug development

Dr. Pacifici reflected on the in-depth talk by the conference’s featured speaker, Christopher Austin, M.D., the director of the National Center for Advancing Translational Sciences (NCATS) of the National Institutes of Health. NCATS, founded in 2011, aims to speed the development of treatments and cures.

I asked Dr. Pacifici to comment on the phrase that struck me from Dr. Austin’s presentation: “The hard work that nobody else wants to do.”

Scientific research is “unsexy” and “difficult to understand,” but Dr. Austin challenged the field to forge ahead, I observed.

“He painted a pretty bleak picture of how we’re sadly finding diminishing returns on our investment,” Dr. Pacifici said regarding drug investigation in general. “In other words, he kind of flipped around Moore’s law. Instead of things getting better and faster, the more money we spend, the fewer treatments we see coming out, especially for the harder neurological diseases.”

Dr. Austin presented to the audience what he called a “truly terrifying fact”: “The number of new drugs approved per billion dollars spent, inflation-adjusted, has gone down by half every nine years, since 1950.”

You can learn why this is so – and its very serious implications for HD – by watching Dr. Austin’s presentation by clicking here.

The HD field hopes to be the exception and the model

Dr. Pacifici pointed to the difficult and complex challenges involved in drug discovery, as illustrated by Dr. Austin.

Everybody wants to be the “star” that “made the compound that turned out to be the cure,” Dr. Pacifici said. But imagine: the compound is there, but no patients are available to do the clinical trial. Or patients participate, but researchers lacked the “outcome measures to see whether people were actually getting better.” Or, antibodies and assays needed to measure the samples derived from patients weren’t there.

Those things are the not-so “sexy” but need to get done, he said.

The HD field will need to overcome the inertia of diminishing returns, Dr. Austin emphasized. Deeply familiar with HD science, he believes that HD as a monogenetic disease has the potential to do so and could serve as the model for treating other, more common neurological disorders.

Dr. Pacifici agreed. He praised the HD research and biotech community not only for its commitment to make sure that key elements of the drug-hunting process are “proactively put in place,” but the “selflessness with which they are shared, so that those don’t represent competitive advantages for one company or another. I think everybody has come to the realization that this is a really hard problem. It’s no use competing with each other. We’re going to have to help each other.”

At the start of his talk on huntingtin-lowering strategies, Ignacio Muñoz-Sanjuán, Ph.D., a CHDI scientist and the co-founder of Factor-H, reminded the audience of the goal of the HD cause: to help individuals like Anyervi (in cap) and Brenda, two youths from South America with juvenile HD (photo by Gene Veritas).

At Therapeutics Conference, landmark study of young gene carriers highlights how Huntington’s disease researchers seek to solve critical puzzles

Armed with ever more impressive data and a deeper understanding of Huntington’s disease, scientists and drug hunters convened at the 15th Annual HD Therapeutics Conference this week, facing the complex puzzles that still hinder the quest for treatments for this deadly neurological disorder.

One of those puzzles: how to not only treat symptoms, but to prevent them, especially in young presymptomatic carriers of the HD gene, so that they don’t have to spend their lives fearing the currently inevitable onset of this devastating disease.

On February 26, Sarah Tabrizi, FRCP, Ph.D., of University College London, answered key questions about what kinds of health consequences young presymptomatic gene carriers suffer decades before they’re likely to develop the disease in midlife.

Previous studies have demonstrated that brain shrinkage can occur as early as 15 to 18 years before predicted age of onset. Ranging in age from 18-40, the 64 gene carriers in Dr. Tabrizi’s HD Young Adult Study went through state-of-the art brain scans and cognitive testing, and also provided samples of blood and cerebrospinal fluid (CSF) for analysis. These at-risk volunteers are, on average, 24 years from estimated onset.

This study, in line with “The Path to Prevention” (one of five major themes of the 2020 conference), is aimed at helping identify the optimal time to treat gene carriers to slow or prevent their neurological decline.

“Comprehensive cognitive testing was normal,” as compared to 67 non-HD-affected individuals, reported Dr. Tabrizi in her presentation to the conference. “There were no significant psychiatric differences, which I found very interesting, because I would have predicted they would’ve been big differences.”

Dr. Tabrizi said that "there’s always been a thought that carrying the HD gene hard-wired you for psychiatric burden,” but the Young Adult Study suggests that such symptoms become more prominent closer to onset.

“I think that was – and I don’t say this lightly – a landmark presentation,” Robert Pacifici, Ph.D., the chief scientific officer for CHDI Foundation, Inc., the conference sponsor, told me today, adding that Dr. Tabrizi’s team carried out the study with “a high degree of rigor and granularity.”

“The participants seem to be remarkably well,” Dr. Pacifici observed. The absence of many of the neurological and other problems typical of HD is an encouraging prospect for developing safe and well-tolerated treatments that could “not just reverse, but actually prevent” HD, he said.

Dr. Pacifici lauded the study volunteers for their "unbelievably selfless participation," including submitting to the study's "incredibly rigorous battery."

Above, Dr. Sarah Tabrizi presenting her talk on the HD Young Adult Study at the 2020 HD Therapeutics Conference, February 26, 2020, and, below, a closeup of Dr. Tabrizi (photos by Gene Veritas, aka Kenneth P. Serbin)

Overall, ‘good news’ for young gene carriers

The young gene carriers in the study did appear to go through a small change in the area of the forebrain known as the striatum, consisting primarily of the putamen and the caudate, the deep brain regions that are most affected by HD. The striatum helps to control our movements and rewards system.

The study found a significant reduction in the size of the putamen, but an insignificant reduction in the caudate. Nevertheless, Dr. Tabrizi explained that, based on this study, these differences (in comparison with the normal subjects) were “not associated with predicted years to onset.”

“So what we now know, based on the data, is that the striatum never appears to be the same size as the control group,” she explained. 

The “very slightly smaller” striatum may suggest a “neurodevelopmental effect” (the way the brain develops) that is “well compensated for,” Dr. Tabrizi said, meaning that the brain adjusts without clear damage. She added that it “might be why the striatum is vulnerable later in life, because it has a double hit.” As mentioned by Dr. Tabrizi, this interpretation resonates with the research of Peg Nopoulos, M.D., who has studied the compromised development of the brains of people affected by juvenile HD.

Alternatively, neurodegeneration early on could be “too subtle and variable” to associate with predicated age of onset, Dr. Tabrizi noted.

Other imaging results showed no decrease in the white matter (the tissue in the brain made of nerve fibers and possibly involved in cognitive problems in HD) or any other aspect of the brain measured in the study, indicating that the subjects were still “very far from onset,” Dr. Tabrizi continued.

“This is really good news,” Dr. Tabrizi stated.

Douglas Langbehn, M.D., Ph.D., a psychiatrist and biostatistician at the University of Iowa who did the statistical analysis for the HD Young Adult Study, listens to Dr. Tabrizi at the Therapeutics Conference (photo by Gene Veritas).

The ongoing search for reliable biomarkers

The study also involved the ongoing search for reliable biomarkers (signs of disease and drug efficacy).

The study detected mutant huntingtin protein in the subjects’ cerebrospinal fluid. “CSF mutant huntingtin was higher in those closer to [predicted] onset, suggesting that some injury is releasing mutant huntingtin [from the brain], but very subtle,” Dr. Tabrizi said.

Several other biomarkers were elevated in the subjects’ CSF, again indicating an early, subtle injury, but most of those subjects had readings showing levels very close to those of the unaffected control subjects, Dr. Tabrizi continued. Furthermore, six other biomarkers were normal, she added.

The Young Adult Study points to the one CSF biomarker in particular, neurofilament light, a marker of brain damage, as potentially helpful in measuring disease progression and treatment response in people decades from onset, Dr. Tabrizi concluded.

A drug that kept neurofilament light at very low levels could prevent degeneration of the brain, she added.

You can watch Dr. Tabrizi’s presentation in the video below.

A moving keynote address

With a record attendance of 380, the conference opened on February 24 with a moving keynote speech by Amy Merkel, a 45-year-old nurse from Wisconsin and the founder of Starfish Yoga.

A small company, Starfish focuses on encouraging constructive coping skills, primarily for people affected by past imprisonment, sexual abuse, and neurological disorders, including HD.

Amy, who titled her talk “Life is Good,” belongs to a family deeply affected by HD. She recounted her extended family’s decades-long struggles with HD. Amy received a standing ovation.

Stay tuned to this blog for additional reporting on the conference, including an overview provided in my interview with Dr. Pacifici.

Above, HD advocate Amy Merkel addresses the 15th Annual Therapeutics Conference, and, below, poses with researchers Dr. Sarah Tabrizi (far left), Leslie Thompson, Ph.D. (second from right), and Gillian Bates, Ph.D. (photos by Gene Veritas).