Prilenia and Ferrer report exploratory pridopidine findings in early ALS as the PREVAiLS Phase 3 trial reaches 60% enrollment, with results expected in 2028.
Written By: Saniya Katakdhond, PharmD
Reviewed By: Pharmacally Editorial Team
Prilenia Therapeutics and Ferrer have reported new findings from a post hoc analysis of pridopidine in amyotrophic lateral sclerosis (ALS), alongside an enrollment update for the ongoing PREVAiLS Phase 3 trial. The findings are being presented at the Northeast Amyotrophic Lateral Sclerosis (NEALS) Consortium 2026 Annual Meeting in Florida.
The analysis included 36 participants with definite or probable ALS, according to the El Escorial Criteria, who were within 18 months of their first disease symptoms. Participants received pridopidine in the HEALEY ALS Platform Trial (NCT04615923) and its open-label extension.
Through Week 48, pridopidine was associated with favorable outcomes across the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R), respiratory measures, and median survival compared with external controls from the Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) database. The comparison used propensity score weighting to improve comparability between the treated subgroup and external controls.
However, the companies’ announcement does not provide numerical effect estimates, confidence intervals, or statistical significance values for these comparisons. The magnitude and precision of the reported associations therefore cannot be assessed from the announcement alone.
Earlier HEALEY Findings Inform Phase 3 Evaluation
The new analysis builds on earlier post hoc subgroup findings from the 24-week placebo-controlled phase of the HEALEY ALS Platform Trial. These findings helped inform the rationale and design of PREVAiLS, which is evaluating pridopidine in a similar early-disease population.
An important limitation is that the pridopidine regimen in HEALEY did not meet its primary endpoint in the overall study population. The earlier subgroup findings and the new analysis do not overturn that result or establish efficacy in the broader ALS population.
The new analysis also has limitations inherent to its design. Propensity score weighting can improve comparability across measured characteristics, but it cannot eliminate residual confounding, selection bias, or differences between trial participants and external-control populations. The results should therefore be considered exploratory rather than confirmatory.
PREVAiLS Reaches Approximately 60% Enrollment
PREVAiLS (NCT07322003) is a global, randomized, placebo-controlled Phase 3 study designed to evaluate the efficacy and safety of pridopidine in approximately 500 participants with ALS early in their disease course.
The study targets participants with definite or probable ALS who are within 18 months of symptom onset. According to the companies, approximately 60% of planned enrollment has been completed. Recruitment is expected to finish in the first quarter of 2027, with topline results anticipated in the first quarter of 2028.
Participants are randomized in a 3:2 ratio to receive pridopidine or placebo during the initial 48-week controlled period, followed by a 48-week open-label extension. The primary endpoint is change from baseline in ALSFRS-R score at Week 48, adjusted for mortality.
Secondary and exploratory assessments include survival, speech, respiratory and bulbar function, quality of life, patient-reported communication outcomes, and plasma biomarkers. These measures will help assess whether any treatment effect extends beyond functional scores to other clinically relevant aspects of ALS.
The randomized, placebo-controlled design is intended to provide a more reliable assessment of treatment effects than comparisons with historical controls. The primary endpoint and the prespecified analysis will be central to determining whether the preliminary findings translate into a reproducible clinical benefit.
Investigational Mechanism and Development Status
Pridopidine is an investigational oral agonist of the sigma-1 receptor (S1R), a protein involved in cellular signaling pathways associated with neuronal function and neuroprotection. This biological rationale supports investigation in neurodegenerative diseases, including ALS and Huntington’s disease, but does not itself demonstrate clinical benefit.
The companies report clinical experience involving more than 1,600 people, predominantly from Huntington’s disease studies, and describe a generally favorable safety and tolerability profile across studies to date. This broader exposure does not independently establish the drug’s safety or efficacy in ALS.
Pridopidine remains investigational and is not approved for commercial use by any regulatory authority.
Clinical Interpretation
The findings provide a rationale for continued evaluation of pridopidine in early ALS, but the available announcement does not establish a treatment benefit. The small subgroup, post hoc design, reliance on external controls, and absence of numerical effect estimates limit interpretation. These limitations are particularly important given that the pridopidine regimen did not meet its primary endpoint in the overall HEALEY study population.
PREVAiLS is the next critical step in determining whether the reported associations translate into clinically meaningful and reproducible effects. Its randomized comparison will provide a stronger basis for assessing functional progression, respiratory outcomes, survival, and safety in early ALS.
References
Prilenia and Ferrer to Share New Pridopidine Data and PREVAiLS Study Updates at the NEALS Consortium 2026 Annual Meeting. Prilenia Therapeutics and Ferrer. 28 October 2026
Pridopidine Phase 3 Study to Evaluate Efficacy and Safety in ALS (PREVAiLS), ClinicalTrials.gov ID NCT07322003
HEALEY ALS Platform Trial – Regimen D Pridopidine, ClinicalTrials.gov ID NCT04615923
About the Writer
Saniya Sanjay Katakdhond (Linkedin) is a Doctor of Pharmacy professional with hands-on experience in patient case review, clinical documentation, medical record analysis, and patient care.
Her hospital experience has strengthened her understanding of clinical conditions, treatment approaches, and multidisciplinary healthcare practices.
With ICH-GCP certification and a research-oriented approach, she brings clinical insight and attention to detail to healthcare content development.
As a healthcare writer, Saniya focuses on translating clinical knowledge and patient-care experience into clear, accurate, and evidence-informed medical content.