New ALS Hope: Pridopidine Enters Pivotal Phase 3 Global Trial

NAARDEN, The Netherlands – March 30, 2026 – A new chapter in the urgent search for effective treatments for Amyotrophic Lateral Sclerosis (ALS) has begun, as biotechnology firm Prilenia Therapeutics and its partner Ferrer announced the enrollment of the first participant in a pivotal Phase 3 clinical trial for the investigational drug pridopidine.

The study, named PREVAiLS, represents a significant milestone for a patient community grappling with a devastating neurodegenerative disease that has very few therapeutic options. The global trial will enroll 500 individuals with rapidly progressive ALS who are early in their disease course, a group with one of the most urgent unmet medical needs. The first participant was enrolled at Mass General Brigham (MGB) in Massachusetts.

Pridopidine targets the sigma-1 receptor (S1R), a protein believed to play a critical role in protecting nerve cells from damage. “Pridopidine is a sigma-1 receptor (S1R) agonist. The S1R has been shown to play a role in stimulating multiple neuroprotective pathways impaired in neurodegenerative diseases, such as ALS and Huntington’s disease,” said Sabrina Paganoni, MD, PhD, Co-Director of the MGH Neurological Clinical Research Institute and a principal investigator for the PREVAiLS study. “Enrolling the first participant in this confirmatory study is a milestone in our search for potential new therapeutic options that may help to slow disease progression, preserve function, maintain speech and prolong survival – key aims of early ALS therapy.”

From Setback to Renewed Hope: The Science Behind Pridopidine

The journey of pridopidine to a large-scale Phase 3 trial is a story of scientific perseverance and precision. The drug was previously evaluated in the HEALEY ALS Platform Trial, a multi-regimen study designed to efficiently test several drug candidates at once. While the pridopidine arm of that trial did not meet its primary or secondary endpoints in the overall study population, a deeper dive into the data revealed a powerful and promising signal.

A peer-reviewed, post-hoc analysis focused on a specific subgroup of 72 participants who, like those in the new PREVAiLS study, had rapidly progressing ALS and were early in their disease course. Within this group, the results were striking. Compared to placebo, pridopidine demonstrated a 32% slowing in the decline of overall function as measured by the ALS Functional Rating Scale-Revised (ALSFRS-R).

Even more compelling were the effects on specific, life-altering symptoms. The analysis showed that pridopidine significantly preserved respiratory function, stabilized bulbar function (which governs speech and swallowing), and dramatically reduced the decline in speech clarity by 93%. Perhaps most importantly, the data suggested a potential survival benefit, with a 57% improvement in survival observed in the pridopidine-treated subgroup. These are the promising findings that Prilenia and Ferrer now seek to confirm in the larger, more definitive PREVAiLS study.

A High-Stakes Trial in a Challenging Landscape

The PREVAiLS study is a 48-week, randomized, placebo-controlled trial that will be conducted at up to 60 leading ALS centers across 13 countries in North America, Europe, and Israel. Its primary goal is to measure the change in a patient’s ALSFRS-R score, adjusted for mortality, providing a comprehensive look at both function and survival. The study will also closely track secondary measures of survival, speech, respiratory function, and quality of life.

The trial launches at a critical time for the ALS community. The landscape for ALS drug development is notoriously difficult, a fact underscored by the recent withdrawal of the drug Relyvrio from the market after it failed its confirmatory Phase 3 trial. This setback highlights the immense challenge of finding therapies that can meaningfully alter the course of this relentless disease and raises the stakes for promising candidates like pridopidine.

Patient advocacy groups, which have long championed innovative trial designs and supported research into promising drug candidates, are watching closely. “The ALS community urgently needs new treatment options that can delay the disease’s relentless progression, and awaits the outcome of this study,” commented Kuldip Dave, Ph.D., Senior Vice President of Research at the ALS Association. “The earlier we can diagnose and treat ALS, the greater the potential to preserve function and maintain quality of life for longer, which are key to making ALS livable until we can cure it.”

A Strategic Alliance to Tackle a Global Challenge

Bringing a potential new therapy through the rigors of late-stage clinical development and to a global market requires a powerful combination of scientific innovation and commercial expertise. The pridopidine effort is backed by a strategic partnership between Prilenia Therapeutics, the agile Dutch biotech company that has stewarded the drug’s development, and Ferrer, a Spanish pharmaceutical firm with a global footprint and a unique mission as a certified B Corporation committed to social justice.

This collaboration leverages Prilenia’s deep expertise in neurodegenerative diseases with Ferrer’s established infrastructure for navigating regulatory pathways and commercializing therapies worldwide. This global reach is essential for a disease like ALS, which affects an estimated 500,000 people across the globe.

Pridopidine has already received Orphan Drug designation for ALS in both the U.S. and the European Union, a status granted to encourage the development of treatments for rare diseases. The drug is also being developed for Huntington’s disease, another devastating neurodegenerative disorder, for which it has received FDA Fast Track designation. As recruitment for PREVAiLS ramps up across the globe, the study represents a focused, data-driven effort to turn a promising scientific signal into a tangible therapeutic reality for patients who have no time to wait.