Pipeline &
Clinical Studies
Pipeline
Pridopidine (45 mg twice daily) is a potent and highly selective, orally administered sigma-1 receptor (S1R) agonist designed to regulate key neuroprotective mechanisms often impaired in neurodegenerative diseases such as HD and ALS.
In April 2025, Prilenia and Ferrer entered into a collaboration and license agreement for the commercialization and co-development of pridopidine in Europe and other select international markets. Prilenia retains full commercialization and development rights to pridopidine in North America, Japan and Asia Pacific.
Prilenia and Ferrer are working hard to bring pridopidine to HD and ALS patients as quickly as possible. Our global pivotal Phase 3 study of pridopidine in ALS has now started enrolling participants, and we expect to start our global pivotal Phase 3 study in HD in the coming months, as we continue discussions with regulatory authorities globally on the pathway to approval.
We also continue our early research on pridopidine, S1R and its neuroprotective role in multiple other CNS indications.
Indication
Preclinical
Phase 1
Phase 2
Phase 3
Vanishing white matter disease*
Potential additional rare neurodegenerative indications
Potential additional common neurodegenerative indications
Pridopidine is an investigational product and has not been approved by the US Food & Drug Administration or other ex-US regulatory agencies. Its safety and efficacy have not yet been determined.
Phase 3 Clinical Trials in ALS and HD
ALS Clinical Trials
PREVAiLS is a pivotal, global, 500-participant Phase 3 study to evaluate efficacy and safety of pridopidine, an investigational drug, in slowing ALS progression (ALSFRS-R) in early, rapidly progressive participants
The design of the potentially registrational pivotal Phase 3 study is informed by, and seeks to confirm, subgroup analysis data from the Phase 2 program in a similar rapid and progressive patient population
PREVAiLS is a 48-week randomized (3:2 pridopidine:placebo), placebo-controlled study, with a 48-week open label extension phase to follow. The study seeks to enroll participants with definite or probable ALS (El Escorial Criteria) who are within 18 months from first onset of disease symptoms. The primary endpoint of PREVAiLS is the change from baseline in ALSFRS-R adjusted for mortality at 48 weeks. Secondary and exploratory endpoints include survival and measures of speech, respiratory function, bulbar function and quality of life, as well as patient-reported outcomes of communication and plasma biomarkers.
More details on PREVAiLS can be found at ClinicalTrials.Gov (NCT07322003) / EU CT Number: 2025-524002-16-00.
HD Clinical Trials
A planned potentially registrational pivotal global Phase 3 study of pridopidine in early manifest HD is expected to start in the coming months.
The study is expected to enroll up to around 400 participants and will be a 52-week randomized (1:1) placebo-controlled study, to be followed by a 2-year open label extension phase.
More details will follow initiation of the study.
Expanded Access
We understand that, in some cases, patients with serious diseases may not be eligible to participate in a clinical study, and there may not be any alternative treatment options for their disease. We are deeply committed to the patient community, and under certain circumstances, we will consider making pridopidine available to individual patients through an expanded access program (also referred to as early access or compassionate use).