Ferrer and Prilenia Therapeutics B.V. today announced the start of the confirmatory PRECISE-HD clinical trial (phase III clinical trial with pridopidine to determine the clinical impact and safety in Huntington's disease (HD) (NCT07609108)). Recruitment has already begun in the US, and other countries are expected to join progressively throughout this year.
Focused on further evaluating the efficacy and safety of pridopidine, an investigational medicine (taken as an oral capsule twice daily), and generating data to support its marketing authorization, the confirmatory PRECISE-HD randomized, double-blind, placebo-controlled study with 400 participants will evaluate the clinical impact of pridopidine on disease progression, functional capacity, motor function, cognitive, speech and quality of life (QoL).
Taking into account the insights gained from previous research, as well as advice and input from the Huntington's disease (HD) patient community, the research community and regulatory authorities, the study will focus on people living with Huntington's disease, from the early to the intermediate phase of the disease (defined as a Total Functional Capacity (TFC) score of between 7 and 13). a Total Motor Score (PMT) ≥ 20 and a score on the Independence Scale ≤ 90%, i.e. people who have experienced some motor changes or an impact on their independent functioning. This will allow any potential effect of the therapy on disease progression to be properly assessed compared to placebo. The PRECISE-HD study will be conducted at up to 75 sites around the world, including the U.S., EU, U.K., and Canada.
Astri Arnesen, President of the European Huntington's Association (EHA), said: "The start of the PRECISE-HD clinical trial is an important and necessary step towards confirming the results of previous studies with pridopidine. This study is designed to work with the group of participants who have already shown positive effects before. The EHA values community involvement in preparations, through consultation with patient organisations as well as the Huntington Community Advisory Council. We have found that Ferrer has taken the contributions very seriously when planning the structure of the trial and its monitoring. I hope that the study will be well received by the community and that recruitment will run as smoothly and quickly as possible. This is a different approach than other ongoing trials, and we need them all."
Dr. Victor Sung, Director of the Division of Movement Disorders at the University of Alabama, Director of the UAB Huntington's Disease Clinic, Director of the HDSA Center of Excellence and member of the PRECISE-HD Steering Committee, said: "In previous studies, pridopidine has demonstrated significant clinical effects in specific circumstances, and this study has been carefully designed to confirm these effects, uniquely incorporating prior knowledge and novel elements specifically designed to provide clarity on the efficacy of the treatment."
Oscar Pérez, Ferrer's Chief Scientific Officer, said: "The start of the PRECISE-HD clinical trial reflects the continued progress of our work in the field of rare neurological diseases and our commitment to advancing rigorous clinical research in areas where unmet medical needs remain significant. Following the initiation of PREVAiLS in amyotrophic lateral sclerosis (ALS) earlier this year, PRECISE-HD is the second phase III study with pridopidine initiated in 2026, reinforcing Ferrer's long-term focus on rare diseases and our responsibility to contribute, together with Prilenia and the wider clinical and patient communities, to the generation of solid evidence for people living with serious neurodegenerative diseases."
The PRECISE-HD study consists of two consecutive phases. A 52-week placebo-controlled phase, in which participants will be randomly assigned to receive pridopidine or placebo in a 1:1 ratio. This will be followed by a 104-week open-label extension phase, in which all eligible participants will receive pridopidine, allowing investigators to assess any potential effects on disease progression for a total of up to three years, compared to matched external control cohorts from longitudinal and multinational observational studies.
The PRECISE-HD study will assess a range of HD-related outcomes, with the primary endpoint being the variation from baseline to week 52 in the combined Unified Huntington's Disease Rating Scale (cUHDRS) score.
More information about the PRECISE-HD study can be found at: www.clinicaltrials.gov NCT07609108. The website of the PRECISE-HD study (www.precisehdtrial.com) will also be available shortly.
[This press release is for informational purposes only. Pridopidine is an investigational medicine and is not approved for commercial use by any regulatory authority. Their safety and efficacy have not been established. The information contained herein does not constitute medical advice. Patients should consult their healthcare professional for guidance on diagnosis or treatment options. Local regulations may vary; This release is not intended to promote or advertise any product.]
About pridopidine
Pridopidine (taken as an oral capsule twice daily), currently under investigation, is a highly selective oral sigma-1 receptor (S1R) agonist. S1R has been shown to play a role in stimulating multiple neuroprotective pathways that are altered in neurodegenerative diseases, such as Huntington's disease (HD) and amyotrophic lateral sclerosis (ALS).
In clinical trials to date, pridopidine has shown a generally favourable safety and tolerability profile, with data from more than 1,600 people (mostly from HD studies), some of whom have been on active treatment for up to seven years.
In addition to HD, pridopidine is in advanced clinical development for ALS. The pivotal Phase III PREVAiLS trial, currently in the recruitment phase for ALS, is based on the results of the Phase II HEALEY ALS Platform trial, conducted in patients with early-stage rapidly progressive disease (defined as definitive or probable ALS according to the El Escorial Criteria (EEC) and less than 18 months from symptom onset).
The investigational drug pridopidine has orphan drug designation for HD and ALS in the US and EU, as well as FDA "Fast Track" designation for the treatment of HD. These designations do not imply that pridopidine has been approved or that its safety and effectiveness have been established.
About Huntington's disease
Huntington's disease (HD) is a rare, hereditary, autosomal dominant neurodegenerative disease that causes functional, motor, cognitive, and behavioral symptoms, ultimately leading to death. HD is caused by a mutation in the huntingtin gene (HTT), and each child of a parent with HD has a 50% chance of developing the disease.
An estimated 100,000 people worldwide have about 100,000 people with HD, and another 300,000 people are at risk of developing it. It is usually diagnosed between the ages of 30 and 50, although HD can appear at any age, including in children and young adults (known as juvenile-onset HD or JHD). The disease progresses slowly over 15 to 20 years, and patients gradually lose their ability to work, communicate, manage their daily lives, and fend for themselves. This increasing disability leads to total dependence on a caregiver and ultimately death.
The only treatments currently available for HD focus on symptom relief and palliative care, with no approved therapies shown to influence indicators of overall disease progression.
About Ferrer
At Ferrer, we use business to fight for social justice. We have long been a company that wants to do things differently; instead of maximizing shareholder returns, we reinvest much of our profit in initiatives that give back to society. Back where it belongs. We go beyond compliance and are guided by the highest standards of sustainability, ethics and integrity. As such, since 2022, we are a B Corp.
Founded in Barcelona in 1959, Ferrer offers transformative solutions for life-threatening diseases in more than one hundred countries. In line with our purpose, we have an increasing focus on pulmonary vascular and interstitial lung diseases and rare neurological disorders. Our 1,800-strong team is driven by a clear conviction: our business is not an end in itself, but a way to change lives. We are Ferrer. Ferrer for good. www.ferrer.com
About Prilenia
Prilenia is a private biopharmaceutical company driven by an unwavering commitment to scientific excellence and accelerating progress for people affected by Huntington’s disease (HD), amyotrophic lateral sclerosis (ALS) and other neurodegenerative disorders. Our mission is simple but urgent: to develop and provide sustainable access to transformative medicines for people affected by devastating neurodegenerative diseases.
Prilenia is partnered with Ferrer for the commercialization and co-development of pridopidine.
The company is incorporated in the Netherlands and backed by leading life sciences investors. For more information, please visit www.prilenia.com, and connect with us on LinkedIn or X (Twitter).
i In April 2025, Prilenia and Ferrer signed a commercialization and co-development agreement for pridopidine. https://news.prilenia.com/press-releases/press-release-details/2025/Prilenia-Enters-into-a-Collaboration-and-License-Agreement-with-Ferrer-for-the-Commercialization-and-Co-Development-of-Pridopidine-in-Europe-and-Other-Select-Markets/default.aspx
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