PREVAiLS Study
Sponsored by Prilenia Therapeutics BV & Ferrer Internacional SA
The PREVAiLS Study is a clinical study that evaluates whether the study drug pridopidine, can help people living with ALS.
The PREVAiLS (Pridopidine Phase 3 Study to Evaluate Efficacy and Safety in ALS) Study is a clinical research study that is being done to evaluate whether the study drug pridopidine, can help people living with ALS. The study will look at the study drug to see if it may slow disease progression and improve speech, breathing, and survival, and to see how safe it is.
The study drug is “investigational”, which means that it has not been approved for use by health authorities, and its effects are still being studied.
In this study participants will receive either the study drug or a placebo (together called the “study medication”). A placebo looks the same as the study drug but does not contain active medication. The study medication comes in capsules that are taken by mouth.
About the study drug: pridopidine
Pridopidine (the study drug) is an investigational medication being studied in ALS and other neurodegenerative diseases. It works by activating a specific protein called the sigma-1 receptor (S1R). S1R helps to protect nerve cells and support their function. It is hoped that, by activating S1R, the study drug may help protect nerve cells from damage and slow the progression of ALS.
The study drug comes in capsules and is taken by mouth.
Study design
- Participation in the study will last for about 2 years
- During the study, participants will have 11 visits to the study center, and 9 phone calls with the study team
Screening (Up to 4 weeks)
During the screening period, you will visit the study center and the study doctor will check if you are able to take part in the study.
Study treatment period
Double blind period (48 weeks)
During the first 48 weeks, participants will be assigned by chance to receive either the study drug or placebo. This part of the study is “double-blind”, which means you, the study doctor, and the study team will not know which one you are taking. For every 3 people who receive the study drug, 2 people will receive the placebo.
The study medication is taken once a day for the first 2 weeks, then twice a day for the remainder of this period. You will have 6 visits to the study center for tests and assessments, and 5 phone calls with the study team.
Open-label extension (OLE) period (48 weeks)
Participants who complete the study treatment period will continue to a 48-week OLE period. During this period, all participants will receive the study drug.
During this 48-week period, you will visit the study center 4 times for tests and assessments, and have 4 phone calls with the study team.
Can I participate in the study?
You, or someone you care for, may be eligible to take part in the PREVAiLS Study if you/they:
- are 18–80 years of age
- have ALS and are within 18 months of first symptoms appearing
- are able to swallow a capsule.
- Slow vital capacity (SVC) greater or equal to 60% predicted.
- 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.
Visit euclinicaltrials.eu for the full PREVAiLS Study eligibility criteria.
Where will the Study take place?
The PREVAiLS Study will take place at multiple centers in the United States, Canada, Europe, and Israel.
Below you can find the participating TRICALS centres which are currently active in the study. You can find the contact information of each centre by clicking on ‘more about this centre’. TRICALS centres can be contacted directly by filling in the contact form, they can provide you with more information and answer any questions you may have. If you experience difficulty contacting a centre, you may reach out directly to the TRICALS operational team at info@tricals.org for support in this process.
More information
More information on the PREVAILS study can be found on the euclinicaltrials.com or clinicaltrials.gov. All information on this page has been extracted from open sources.
Participating TRICALS centres

Centrum Medyczne Linden
Poland, Krakow
Jakub Antczak
Neurologist and Neurophysiologist

Karolinska Institute
Sweden, Stockholm
Caroline Ingre
Associate Professor of Neurology

Medical University of Warsaw
Poland, Warsaw
Magdalena Kuzma-Korakiewicz
Professor of Neurology

Royal Stoke University Hospital
United Kingdom, Stoke on Trent
Tom Lambert
Neurologist

UMC Utrecht
Netherlands, Utrecht
Leonard van den Berg
Professor of Neurology

University Hospital Bonn
Germany, Bonn
Patrick Weydt
Neurologist

University Hospital of Northern Sweden, Umeå
Sweden, Umeå
Peter M. Andersen
Professor of neurology

UZ Leuven
Belgium, Leuven
Philip van Damme
Professor of Neurology