Pridopidine Phase 3 Study to Evaluate Efficacy and Safety in ALS (PREVAiLS)

April 23, 2026 updated by: Prilenia

A Phase 3, Randomized, Double-blind, Placebo-controlled Study to Evaluate the Efficacy and Safety of Pridopidine in Participants With Amyotrophic Lateral Sclerosis

The goal of this clinical trial is to learn if the drug pridopidine works to treat amyotrophic lateral sclerosis in adults. It will also help to learn about the safety of pridopidine. The main question it aims to answer is:

Does pridopidine slow disease progression of ALS?

Researchers will compare pridopidine to a placebo (a look-alike substance that contains no drug) to see if pridopidine works to treat ALS.

Participants will:

Take pridopidine or a placebo by mouth every day for 48 weeks. Afterwards, all participants will take pridopidine for another 48 weeks.

Visit the clinic once every 1-3 months for checkups and tests

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

This is a Phase 3, randomized study consisting of a double-blind placebo-controlled (DBPC) period followed by an open-label extension (OLE) to evaluate the efficacy and safety of pridopidine administered orally at a dose of 45 mg twice a day in adult participants with early and rapidly progressing ALS. Standard of care treatments (e.g. riluzole, edaravone and Nuedexta) will be allowed as long as participants are on a stable dose for at least 4 weeks prior to dosing. In the DBPC period, participants will be randomized in a 3:2 ratio to the pridopidine and placebo arms.

In the DBPC period, participants will receive pridopidine or placebo for 48 weeks. In the OLE period, all participants will receive pridopidine for 48 weeks, while maintaining the blind to their original randomization for both the participant as well as the Investigator and other clinical staff. The total study duration per participant will be 102 weeks including screening and follow up.

Throughout the study, participants will be assessed through on-site clinic visits and virtual visits (via telephone).

Study Type

Interventional

Enrollment (Estimated)

500

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Executive Director Clinical Operations
  • Phone Number: 857-574-5755
  • Email: MedInfo@prilenia.com

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Key Inclusion Criteria:

  • Definite ALS or Probable ALS using the El Escorial criteria.
  • Symptom onset of ≤18 months at screening.
  • Slow vital capacity (SVC) greater or equal to 60% predicted.
  • Treatment Research Initiative to Cure ALS (TRICALS) Risk Profile Calculator score, based on the European Network for the Cure of ALS (ENCALS) survival prediction model, in the range of -6 to -2, inclusive, at screening.
  • Able to swallow a capsule.

Key Exclusion Criteria:

  • Presence of tracheostomy or permanent assisted ventilation.
  • Clinically significant heart disease, clinically significant history of arrhythmia, symptomatic or uncontrolled atrial fibrillation despite treatment, or asymptomatic sustained ventricular tachycardia, or presence of left bundle branch block.
  • Presence of unstable psychiatric disease, cognitive impairment, dementia or substance abuse that would impair ability of the participant to provide informed consent and participate in the study.
  • Clinically significant and/or unstable medical condition (other than ALS) that may either pose a clinically meaningful risk to the participant and/or to study completion.
  • Use of medications that prolong QT interval.
  • Previous treatment with pridopidine, gene therapy, or antisense oligonucleotides.
  • Confirmed mutation in the SOD1, FUS or C9orf72 gene.
  • Pregnancy.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Pridopidine
Pridopidine hard gelatin capsules of 45 mg strength. During titration period 1 capsule taken orally in the morning for 2 weeks. During the main treatment period, 1 capsule in the morning and 1 capsule in the afternoon taken orally. Total daily dose of 90 mg.
Drug: Pridopidine
Pridopidine hard gelatin capsule.
Placebo Comparator: Placebo
Placebo hard gelatin capsules. During titration period 1 capsule taken orally in the morning for 2 weeks. During the main treatment period, 1 capsule in the morning and 1 capsule in the afternoon taken orally.
Drug: Placebo
Placebo hard gelatin capsule.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change from baseline through Week 26 and Week 48 in the Revised ALS Functional Rating Scale (ALSFRS-R) total score adjusted for mortality
Time Frame: Baseline to Week 48
The ALSFRS-R encompasses 12 questions grouped into 4 domains to assess bulbar symptoms, limb and trunk functionality, respiratory symptoms, and the need for percutaneous endoscopic gastrostomy (PEG), non-invasive ventilation, or tracheostomy with invasive ventilation. Each function is scored from 0 (no ability) to 4 (normal), with a minimum total score of 0 and maximum total score of 48. Higher scores indicate better functioning.
Baseline to Week 48

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Overall survival at Week 96
Time Frame: Baseline to Week 96
Time to death in days from baseline as assessed at the end of open-label extension (OLE) period
Baseline to Week 96
Change from baseline through Week 26 and Week 48 in speaking rate as measured by quantitative speech assessment in the clinic
Time Frame: Baseline to Week 48
Baseline to Week 48
Change from baseline through Week 48 in intelligibility of speech by quantitative speech assessment in the clinic.
Time Frame: Baseline to Week 48.
Baseline to Week 48.
Change from baseline through Week 48 in percent predicted slow vital capacity (SVC)
Time Frame: Baseline to Week 48
SVC measures the maximal amount of air exhaled in a relaxed expiration from full inspiration to residual volume. SVC is assessed in the sitting position with a spirometer.
Baseline to Week 48
Change from baseline through Week 48 in the Bulbar subdomain of the ALSFRS-R
Time Frame: Baseline to Week 48
Measures decline in bulbar function.
Baseline to Week 48
Change from baseline through Week 48 in the Amyotrophic Lateral Sclerosis Assessment Questionnaire - 40 (ALSAQ-40)
Time Frame: Baseline to Week 48
ALSAQ-40 includes 40 items/questions with 5 discrete scales including physical mobility (10 items), activities of daily living and independence (10 items), eating and drinking (3 items), communication (7 items), and emotional reactions (10 items). The questions refer to two weeks prior to the day of the application and the answers are given according to the following variables: never, rarely, sometimes, frequently and always. The score ranges from 0 to 100; the higher the score, the worse the quality of life.
Baseline to Week 48

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Prilenia

Collaborators

Ferrer Internacional S.A.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 1, 2026

Primary Completion (Estimated)

March 1, 2028

Study Completion (Estimated)

March 1, 2029

Study Registration Dates

First Submitted

January 5, 2026

First Submitted That Met QC Criteria

January 5, 2026

First Posted (Actual)

January 7, 2026

Study Record Updates

Last Update Posted (Actual)

April 24, 2026

Last Update Submitted That Met QC Criteria

April 23, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • PL101-ALS301 / FNP254-CT-2501

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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