A Phase 3 interventional study of Pridopidine and Placebo in Amyotrophic Lateral Sclerosis, sponsored by Prilenia. Recruiting at 56 sites in 13 countries. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-10-27.
Sponsored by Prilenia · Phase 3, Interventional, and Treatment
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
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).
978 studies on the registry are indexed under Amyotrophic Lateral Sclerosis; 277 are open to participants now.
This study's planned enrollment of 500 is above the median of 38 across 662 interventional studies indexed under Amyotrophic Lateral Sclerosis.
Browse Amyotrophic Lateral Sclerosis studies →Prilenia is the lead sponsor of 9 studies on the registry; 2 are open to participants now.
Of its 5 completed or terminated interventional studies of FDA-regulated products, 5 (100%) have results posted.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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
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
Pridopidine hard gelatin capsule.
Placebo hard gelatin capsule.
Change from baseline through Week 26 and Week 48 in the Revised ALS Functional Rating Scale (ALSFRS-R) total score adjusted for mortality
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.
Time frame: Baseline to Week 48
Overall survival at Week 96
Time to death in days from baseline as assessed at the end of open-label extension (OLE) period
Time frame: 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
Change from baseline through Week 48 in intelligibility of speech by quantitative speech assessment in the clinic.
Time frame: Baseline to Week 48.
Change from baseline through Week 48 in percent predicted slow vital capacity (SVC)
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.
Time frame: Baseline to Week 48
Change from baseline through Week 48 in the Bulbar subdomain of the ALSFRS-R
Measures decline in bulbar function.
Time frame: Baseline to Week 48
Change from baseline through Week 48 in the Amyotrophic Lateral Sclerosis Assessment Questionnaire - 40 (ALSAQ-40)
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.
Time frame: Baseline to Week 48
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Amyotrophic Lateral Sclerosis →
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